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HomeMy WebLinkAboutTIR-4166 TECHNICAL INFORMATION REPORT Proposed Plat of Elliott Farms Renton, Washington Prepared for: TriPointe Homes 15900 S.E. Eastgate Way, Suite 300 Bellevue, WA 98008 December 9, 2020 Revised February 25, 2021 Revised April 21, 2021 Our Job No. 21397 04/21/21 APPROVED 07/14/2021 msippo DEVELOPMENT ENGINEERING DIVISION SURFACE WATER UTILITY JFarah 07/14/2021 Technical Information Report Proposed Plat of Elliott Farm Renton, Washington Our Job No. 21397 TABLE OF CONTENTS 1.0 PROJECT OVERVIEW Figure 1 – TIR Worksheet Figure 2 – Site Location Figure 3 – Drainage Basins, Subbasins, and Site Characteristics Figure 4 – Soils Figure 5 – FEMA Map Figure 6 – Sensitive Areas Map 2.0 CONDITIONS AND REQUIREMENTS SUMMARY 2.1 Analysis of the Core Requirements 2.2 Analysis of the Special Requirements 3.0 OFF-SITE ANALYSIS 4.0 FLOW CONTROL, LOW IMPACT DEVELOPMENT (LID), AND WATER QUALITY FACILITY ANALYSIS AND DESIGN A. Existing Site Hydrology B. Developed Site Hydrology C. Performance Standards D. Flow Control System E. Water Quality System 5.0 CONVEYANCE SYSTEM ANALYSIS AND DESIGN 6.0 SPECIAL REPORTS AND STUDIES 7.0 OTHER PERMITS 8.0 CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN (CSWPPP) ANALYSIS AND DESIGN 9.0 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT 10.0 OPERATIONS AND MAINTENANCE MANUAL APPENDIX A - Lower Cedar River Basin and Nonpoint Pollution Action Plan Tab 1.0 21397.002-TIR.docx 1.0 PROJECT OVERVIEW The proposed Plat of Elliott Farms is an attached single-family residential project consisting of 45 lots, zoned R-14. The tax parcel number is 2223059004 and is 6.07 acres in size. The site is located on the south side and adjacent to Maple Valley Hwy (WA-169) at the eastern terminus of 140th Way SE (Private Road) in the Molasses Creek Condominiums, in a portion of Section 22, Township 23 North, Range 5 East, W.M., in the City of Renton. Please refer to the vicinity map in the section. The site is rectangular in shape with 691.70’ of frontage along Maple Valley Hwy (WA-169). Condominium units, known as Molasses Creek Phase 1, is located on the west side of the project that provides access into the project. A single family residential development, known as Pioneer Place, is located to the east and a single family residence is located south. A wetland exists at the southwest corner of the site with a 50’ buffer. This site is currently undeveloped, but contains remnants from an existing farm, including partially buried building foundations and concrete slabs. Existing on-site utilities were constructed along the northern portion of the site for this development. On-site soils are mapped as Newberg (till soils). Please refer to the Soils Map in this section. The subject property has been planned for development as a future phase of Cedarwood or Molasses Creek Condominiums. Development of the Elliott Farms site was delayed by a prior King County historical designation, then annexation into Renton, and finally by the economic downturn that affected all property development. As such, a formal development application of the subject Elliott Farms site has been delayed until now. What remains consistent is that the development of the site was planned as a future phase of either Cedarwood or Molasses Creek Condominiums, and the drainage systems for those projects accommodated the development of the subject Elliott Farms site. The project has a Pre-Annexation Agreement between the City of Renton and Cedar River Lightfoot, Inc, which is included in Section 7.0 of this TIR. The proposed on-site road will utilize vertical curb and gutter with depressed curb and sidewalk at driveway connections. The road will connect to the existing 140th Way S.E that was stubbed to the property by Molasses Creek. The private alley will be extended into the site to provide private access and circulation. An emergency access will be provided to WA-169. Frontage improvements along WA-169 are required, including new asphalt, new curb and gutter, sidewalk, and planter strip. The project is proposing to install a piped conveyance system along the frontage to convey the runoff from WA-169 and a portion of the site to the existing ditch along Molasses creek frontage. The on-site topography is generally flat. The southwest corner of the project gently slopes toward the wetland. Please refer to Section 4.0 for a discussion on maintaining wetland hydrology. The remaining portion of the site drains into the roadside ditch along WA-169. There is an existing drainage ditch along the east side of the project that conveys off-site upstream flows from the southeast. The elevations on the site range from 107 to 87. The project will be mass graded to provide flat home sites for the future homes. It is expected that that site will import soils to provide necessary cover over existing and future utilities. Please refer to Section 6 containing special reports and studies including a Geotechnical Report, Wetland report, and a Cultural Resources Assessment. The drainage system for this project is required to meet the requirements of the 2009 King County Surface Water Design Manual (KCSWDM), and the 2010 City of Renton Amendments to the KCSWDM. Flow control is exempt for this project as the projects drainage flows to the Cedar River which is listed as a receiving water in core requirement no. 3. The water quality facility (wetpond) that was built with previous development was sized to accommodate the project. Please refer to Section 4.0 for a more detailed summary. Figure 1 TIR Worksheet KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2009 Surface Water Design Manual 1/1/09 1 21397.TIR Worksheet.doc Part 1 PROJECT OWNER AND PROJECT ENGINEER Part 2 PROJECT LOCATION AND DESCRIPTION Project Owner TriPointe Homes Phone Address 15900 SE Eastgate Way, Suite 300 Bellevue, WA 98008 Project Engineer Mark Sumrok Company Barghausen Consulting Engineers , Inc. Phone (425) 251-6222 Project Name Elliott Farm DDES Permit # Location Township 23N Range 5E Section 22 Site Address not available, Renton, WA Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS Landuse Services Subdivision / Short Subd. / UPD Building Services M/F / Commercial / SFR Clearing and Grading Right-of-Way Use Other DFW HPA COE 404 DOE Dam Safety FEMA Floodplain COE Wetlands Other Shoreline Management Structural Rockery/Vault/ ESA Section 7 Part 5 PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review Full / Targeted / (circle): Large Site Date (include revision Decmeber 4, 2020 dates): Date of Final: Site Improvement Plan (Engr. Plans) Type (circle one): Full / Modified / Small Site Date (include revision December 4, 2020 dates): Date of Final: Part 6 ADJUSTMENT APPROVALS Type (circle one): Standard / Complex / Preapplication / Experimental / Blanket Description: (include conditions in TIR Section 2) Date of Approval: KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2009 Surface Water Design Manual 1/1/09 2 21397.TIR Worksheet.doc Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes / No Start Date: 4/2021 Completion Date: 8/2023 Describe: Site is located in the Zone 2 wellhead Protection Area Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : Special District Overlays: Drainage Basin: Lower Cedar River Basin – Mainstem -2 Stormwater Requirements: Part 9 ONSITE AND ADJACENT SENSITIVE AREAS River/Stream Lake Wetlands Closed Depression Floodplain Other Zone 2 Aquifer Protection Area Steep Slope Erosion Hazard Landslide Hazard Coal Mine Hazard Seismic Hazard Habitat Protection Part 10 SOILS Soil Type Slopes Erosion Potential Newberg 0-2 Percent slight High Groundwater Table (within 5 feet) Sole Source Aquifer Other Seeps/Springs Additional Sheets Attached KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2009 Surface Water Design Manual 1/1/09 3 21397.TIR Worksheet.doc Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION / SITE CONSTRAINT Core 2 – Offsite Analysis Sensitive/Critical Areas SEPA Other Additional Sheets Attached Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Threshold Discharge Area: (name or description) Direct Discharge to Cedar River Core Requirements (all 8 apply) Discharge at Natural Location Number of Natural Discharge Locations: 1 Offsite Analysis Level: 1 / 2 / 3 dated: November 6, 2018 Flow Control Level: 1 / 2 / 3 or Exemption Number Direct Discharge (incl. facility summary sheet) Small Site BMPs Conveyance System Spill containment located at: N/A Erosion and Sediment Control ESC Site Supervisor: TBD Contact Phone: TBD After Hours Phone: TBD Maintenance and Operation Responsibility: Private / Public If Private, Maintenance Log Required: Yes / No Financial Guarantees and Provided: Yes / No Liability Water Quality Type: Basic / Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption No. Landscape Management Plan: Yes / No Special Requirements (as applicable) Area Specific Drainage Type: CDA / SDO / MDP / BP / LMP / Shared Fac. / None Requirements Name: Floodplain/Floodway Delineation Type: Major / Minor / Exemption / None 100-year Base Blood Elevation (or range): Datum: Flood Protection Facilities Describe: N/A Source Control Describe landuse: N/A (comm./industrial landuse) Describe any structural controls: N/A KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2009 Surface Water Design Manual 1/1/09 4 21397.TIR Worksheet.doc Oil Control High-use Site: Yes / No Treatment BMP: Maintenance Agreement: Yes / No with whom? Other Drainage Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION Clearing Limits Cover Measures Perimeter Protection Traffic Area Stabilization Sediment Retention Surface Water Control Dewatering Control Dust Control Flow Control MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION Stabilize Exposed Surfaces Remove and Restore Temporary ESC Facilities Clean and Remove All Silt and Debris Ensure Operation of Permanent Facilities Flag Limits of SAO and open space preservation areas Other Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facility Summary and Sketch) Flow Control Type/Description Water Quality Type/Description Detention Infiltration Regional Facility Shared Facility Flow Control BMPs Other Biofiltration Wetpool Media Filtration Oil Control Spill Control Flow Control BMPs Other Wetpond KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2009 Surface Water Design Manual 1/1/09 5 21397.TIR Worksheet.doc Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS Drainage Easement Covenant Native Growth Protection Covenant Tract Other Cast in Place Vault Retaining Wall Rockery > 4' High Structural on Steep Slope Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knowledge the information provided here is accurate. Signed/Date 3/05/2021 3/05/21 Figure 2 Site Location ELLIOTT FARMS 21397 ELLIOTT FARMS 21397 DIVISION 4DIVISION 3-MOLASSESCREEK (PHASE 1)ELLIOT FARMSMOLASSESCREEK (PHASE 2)DIVISION 2DIVISION 1 Figure 3 Drainage Basins, Subbasins, and Site Characteristics IN COMPLIANCE WITH CITY OF RENTON STANDARDSTED-40-4166 TRIPOINTE(425) 455-290015900 SE EASTGATE WAY. SUITE 300ELLIOTT FARMS LUA: 15-000242 C: 20-005641ELLIOTT FARMS PR: 15-003117 ELLIOTT FARMSSCALE: 1"=200' ONLY192021222324252627282930313234353637383940414243444521341817161514651112137338910ONLYIN COMPLIANCE WITH CITY OF RENTON STANDARDSTED-40-4166 TRIPOINTE(425) 455-290015900 SE EASTGATE WAY. SUITE 300BELLEVUE, WA 98008ELLIOTT FARMS LUA: 15-000242 C: 20-005641ELLIOTT FARMS PR: 15-003117 ELLIOTT FARMS”SCALE: 1"=50' ONLYSCALE: 1"=50'IN COMPLIANCE WITH CITY OF RENTON STANDARDSTED-40-4166 TRIPOINTE(425) 455-290015900 SE EASTGATE WAY. SUITE 300BELLEVUE, WA 98008ELLIOTT FARMS LUA: 15-000242 C: 20-005641ELLIOTT FARMS PR: 15-003117 ELLIOTT FARMS” XSITE Figure 4 Soils Map ELLIOTT FARM 21397 Figure 5 FEMA Map ELLIOTT FARM 21397 Figure 6 Sensitive Areas Map ELLIOTT FARM 21397 Tab 2.0 21397.002-TIR 2.0 CONDITIONS AND REQUIREMENTS SUMMARY 2.1 Analysis of the Core Requirements Core Requirement No. 1: Discharge at the Natural Location. Response: The project will be maintaining the natural discharge location for the site. The runoff from the existing site drains to the existing drainage ditch along WA-169, where it is conveyed westerly to the existing water quality drainage facility built my previous development, then outfall to the Cedar River. The project will be discharging developed drainage at two locations. A portion of the developed run-off will discharge to the existing conveyance system in Molasses Creek, which also drains to the existing water quality pond. The other portion of the site will discharge developed flows to the proposed conveyance system along WA-169 which also drains to the existing water quality drainage facility. Please refer to the Level 3 downstream drainage analysis in Section 3.0. Core Requirement No. 2: Off-Site Analysis. Response: An Off-Site Analysis has been performed pursuant to the 2009 KCSWDM. See Section 3.0 for the Level 3 Off-Site Analysis. Core Requirement No. 3: Flow Control. Response: Flow control is exempt for this project. The project will be discharging flows to the Cedar River, which is listed as a Major Receiving Water in the 2009 KCSWDM. The project is less than on-half mile to the 100 year flood plain, therefor, the project can us the direct discharge exemption identified in Section 1.2.3 in the 2009 KCSWDM and the 2010 City of Renton Amendments to the KCSWDM. See Section 4.0 for more information. Core Requirement No. 4: Conveyance System. Response: A 100 year conveyance capacity analysis of the existing pipe conveyance system through Molasses Creek to the existing wetpond has been performed to show the system has adequate capacity for the future predicted developed flows from Elliott Farms and is included in Section 3. The remainder of the conveyance system will be designed in accordance with the 2009 KCSWDM and the 2010 City of Renton Amendments to the KCSWDM. A Conveyance and backwater analysis for the on-site pipes is provided in Section 5. Core Requirement No. 5: Erosion and Sediment Control. Response: Temporary erosion and sedimentation control measures will include stabilized construction entrances, perimeter run-off control, cover practices, sedimentation facilities, sediment pond and trap, and construction sequencing per the 2017 RSWDM and DOE Guidelines. A sediment pond will be located at the northwest corner of the site and a sediment trap will be provided at the northeast corner of the site. Please refer to section 8 and the construction plans for ESC measures. Core Requirement No. 6: Maintenance and Operations. Response: The majority of the new roadways and conveyance system will be privately maintained. The existing water quality drainage facility is publically maintained by the City of Renton; therefore, no operation and maintenance manuals is required for the drainage facility. Please refer to Section 10.0. 21397.002-TIR.docx Core Requirement No. 7: Financial Guarantees and Liability. Response: A Financial Guarantee (bond) will be provide prior to the start of construction. The Site Improvement Bond Quantity Worksheet was prepared per the city of Renton standards and is provided in Section 9.0 of this report to establish a bond amount for site improvements and site stabilization. Core Requirement No. 8: Water Quality. Response: Basic water quality is required for this project. The project will be utilizing the existing wetpond built with previous development and sized for this project. Please refer to Section 4.0 for a more detailed description of the existing water quality facility and sizing calculations. 2.2 Analysis of the Special Requirements Special Requirement No. 1: Other Adopted Area-Specific Requirements. Response: The proposed project is not located in a designated Critical Drainage Area. Special Requirement No. 2: Flood Hazard Area Delineation. Response: As indicated by the FEMA Map included in this report, the proposed site does not lie within a floodplain or floodway of a stream, so this special requirement does not apply. Special Requirement No. 3: Flood Protection Facilities. Response: This project does not rely on an existing flood protection facility or propose to modify or construct a new flood protection facility, so this special requirement does not apply. Special Requirement No. 4: Source Control. Response: The project does not require a commercial building or commercial site development permit, so this special requirement does not apply. Special Requirement No. 5: Oil Control. Response: This site is not classified as a High Use Site given the criteria in the 2009 KCSWDM, so this special requirement does not apply and no special control treatment is necessary. Special Requirement No. 6: Aquifer Protection Area Response: The project site is within Zone 2 of the Aquifer Protection Area. HEARING EXAMINERS DECISION DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT Project Location Map HEX Report A. REPORT TO THE HEARING EXAMINER HEARING DATE: August 9, 2016 Project Name: Elliott Farms Preliminary Plat Owners: Lennon Investments, Inc., 35815 SE David Powell Road, Fall City, WA 98024 Cedar River Lightfoot, Inc., 14410 Bel-Red Road, Suite 200, Bellevue, WA 98007 Applicants: Patrick O. Lennon, 35815 SE David Powell Road, Fall City, WA 98024 Todd Levitt, 14410 Bel-Red Road, Suite 200, Bellevue, WA 98007 Contact: Ivana Halvorsen, Barghausen Consulting Engineers, Inc. 18215 - 72nd Ave S, Kent, WA 98032 File Number: LUA15-000242, ECF, PP, SA-H, MOD Project Manager: Clark H. Close, Senior Planner Project Summary: The applicant is requesting Preliminary Plat, Hearing Examiner Site Plan Review, SEPA Environmental Review, and a Street Modification for a 45-lot subdivision for the future construction of attached two- and three-unit buildings. The 6.07-acre site is located along SR-169 between 140th Way SE and 145th Ave SE within the Residential-14 zoning district (APN 2223059004). The subdivision of 45 residential lots and 8 tracts would result in a net density of 9.7 dwelling units per acre. The tracts include 47,911 sf of critical areas, 60,731 sf of open space and 4,915 sf for alleys. The fee simple lots would range in size from 2,217 sf to 3,939 sf with an average lot size of 2,586 sf. Primary access to the development would be via a managed public road access from SR 169 that runs through the development and connects to an existing private lane at Molasses Creek Condominiums. Secondary access to the lots would be available through the existing private lane to 140th Way SE and SR 169. The undeveloped site contains high erosion hazards, landslide hazards and a Category II wetland with a 50-foot buffer. The site is in the Cedar River drainage basin and outside the 100-year floodplain limits. Stormwater would be conveyed to the existing water quality pond located west of 140th Way SE. Soils primarily consist of Newburg Silt Loam (Ng). Approximately 9,000 cubic yards of cut and 20,000 cubic yards of fill are anticipated for the project. The site contains 114 significant trees. The project would remove 31 trees within the development area and replant 120 trees. All 74 significant trees in the wetland and buffer are proposed to be retained. Project Location: SR 169 East of 140th Way SE (APN 222305-9004) Site Area: 6.07 acres City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 2 of 31 Hex Report B. EXHIBITS: Exhibits 1-27: As shown in the SEPA Environmental Review Report Exhibit 28: Hearing Examiner Staff Recommendation (dated August 9, 2016) Exhibit 29: Renton School District Capacity email (received date May 6, 2015) Exhibit 30: Public Comment Letter from Emily O’Meara (received date May 14, 2015) Exhibit 31: Public Comment from Harrison and staff’s response letter (dated May 22, 2016) Exhibit 32: Public Comment from Thierry and staff’s response letter (dated May 22, 2016) Exhibit 33: Public query email from Bonaudi (initially received date February 15, 2016) Exhibit 34: Muckleshoot Indian Tribe Fisheries Division Habitat Program email (initially received date June 1, 2015 Exhibit 35: Environmental “SEPA” Determination, ERC Mitigation Measures and Advisory Notes Exhibit 36: Advisory Notes to the Applicant: Traffic Concurrency Test – Elliott Farms Exhibit 37: Affidavit of mailing and posting Exhibit 38: WSDOT approved Channelization Plan for SR 169 Exhibit 39: Preliminary Plat Plan with Houses and Landscaping (Sheets 1 and 2) Exhibit 40: Preliminary Building Elevations, Roof Plans and Floor Plans (A2.1, A2.2, and A2.3) Exhibit 41: Draft Elliott Farms Homeowners Association CCR’s Exhibit 42: Pre-Annexation Development Agreement Cedar River Lightfoot, Inc. Exhibit 43: T-Shaped Hammerhead Alley (Marked-up Old Site Plan) C. GENERAL INFORMATION: 1. Owner(s) of Record: Patrick O. Lennon, 35815 SE David Powell Road, Fall City, WA 98024; Todd Levitt, 14410 Bel-Red Road, Suite 200, Bellevue, WA 98007 2. Zoning Classification: Residential-14 (R-14) 3. Comprehensive Plan Land Use Designation: Residential High Density (RHD) 4. Existing Site Use: Vacant 5. Critical Areas: Low to high erosion hazards, low to medium landslide hazards, and a Category II wetland City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 3 of 31 Hex Report D. HISTORICAL/BACKGROUND: Action Land Use File No. Ordinance No. Date Comprehensive Plan N/A 5758 06/22/2015 Zoning N/A 5758 06/22/2015 Pre-Annexation Development Agreement N/A N/A 04/21/2008 Annexation (Aqua Barn) A-07-001 5373 06/09/2008 E. PUBLIC SERVICES: 1. Existing Utilities a. Water: Water service will be provided by Cedar River Water and Sewer District. b. Sewer: Wastewater service is provided by the City of Renton. There is an 8-inch sanitary sewer main in Park Ave N, an 8-inch main in N 40th Street and a 10-inch main in Lake Washington Blvd. c. Storm Water: There is conveyance/structure system at NE corner of the subject property. 2. Streets: There are no frontage improvements on Maple Valley Highway (SR 169). 3. Fire Protection: City of Renton Fire Authority (RFA) F. APPLICABLE SECTIONS OF THE RENTON MUNICIPAL CODE: 1. Chapter 2 Land Use Districts a. Section 4-2-020: Purpose and Intent of Zoning Districts b. Section 4-2-060: Zoning Use Table – Uses Allowed in Zoning Designations c. Section 4-2-110A: Development Standards for Residential Zoning Designations d. Section 4-2-115: Residential Design and Open Space Standards 2. Chapter 3 Environmental Regulations a. Section 4-3-050: Critical Area Regulations 6. Neighborhood Characteristics: a. North: Residential Low Density (RLD) Comprehensive Plan Land Use Designation; Resource Conservation (RC) zone b. East: Residential Medium Density (RMD) Comprehensive Plan Land Use Designation; Residential-8 DU/AC (R-8) zone c. South: Residential Low Density (RLD) and Residential Medium Density (RMD) Comprehensive Plan Land Use Designations; Resource Conservation (RC) and Residential-8 DU/AC (R-8) zones (King County: Urban Residential, Medium (4-12 du/ac (um) Comprehensive Plan Land Use Designation and R-6 Residential, six DU per acre) d. West: Residential Low Density (RLD) and Residential High Density (RHD) Comprehensive Plan Land Use Designations; Resource Conservation (RC) and Residential-14 DU/AC (R-14) zones 7. Site Area: 264,409 SF (6.07 acres) City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 4 of 31 Hex Report 3. Chapter 4 City-Wide Property Development Standards 4. Chapter 6 Streets and Utility Standards 5. Chapter 7 Subdivision Regulations a. Section 4-7-080: Detailed Procedures for Subdivision b. Section 4-7-120: Compatibility with Existing Land Use and Plan – General Requirements and Minimum Standards c. Section 4-7-150: Streets – General Requirements and Minimum Standards d. Section 4-7-160: Residential Blocks – General Requirements and Minimum Standards e. Section 4-7-170: Residential Lots – General Requirements and Minimum Standards 6. Chapter 9 Permits – Specific a. Section 4-9-250: Variances, Waivers, Modifications, and Alternates 7. Chapter 11 Definitions G. APPLICABLE SECTIONS OF THE COMPREHENSIVE PLAN: 1. Land Use Element H. FINDINGS OF FACT (FOF): 1. The applicant is requesting a Preliminary Plat, Hearing Examiner Site Plan, SEPA Environmental Review, and a Street Modification for the construction of 45 new attached two- and three-unit buildings. 2. The 6.07-acre site is located at 14207 Maple Valley Hwy LOT, within the SE ¼ of Section 23, Township 22 North, Range 5 East, W.M., and consists of one (1) parcel (Parcel Number 22305-9004). 3. The project site is currently vacant, formerly occupied by a working dairy farm with a residence and garage on the west side of the property and several barns and structures located on the south side of the site. 4. All former buildings and structures have been demolished. The only evidence of the former structures is the remaining concrete foundations and floor slabs from both the residence and barns. 5. The proposed development would result in a net density of 9.7 dwelling units per acre. 6. The Planning Division of the City of Renton accepted the above master application for review on April 13, 2015 and determined the application complete on May 5, 2015. The project was placed on hold on May 5, 2015 and taken off hold on July 28, 2016. The project was placed back on hold on September 15, 2016 and taken back off hold on January 8, 2016. 7. On January 27, 2016, the City of Renton reached out to Washington State Department of Transportation (WSDOT) to consider allowing a direct public connection to SR 169/Maple Valley Highway. The applicant was charged with submitting a channelization plan for the intersection of Road A and SR 169, subject to review by both the City of Renton and WSDOT for compliance with city and state transportation policies and guidelines. 8. The Planning Division of the City of Renton accepted resubmittal items for review and re-noticed the subject property on June 21, 2016. The re-noticed project complies with the 120-day review period. 9. The City ordinances governing the development of land up to and including adopted Ordinance No. 5755. 10. Primary access to the development would be via a channelized public road access from SR 169 that runs through the development and connects to an existing private lane at Molasses Creek Condominiums. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 5 of 31 Hex Report Secondary access to the lots would be available through the existing private lane to 140th Way SE and SR 169. 11. The property is located within the Residential High Density (RHD) Comprehensive Plan Land Use Designation. 12. The site is located within the Residential-14 (R-14) zoning classification. 13. Surrounding uses include multi-family and single family residences in the Residential-14 (R-14) and Residential-8 (R-8) zones, respectively. 14. There are approximately 114 significant trees located onsite of which the applicant is proposing to retain 74 within the wetland and wetland buffer area. 15. The site contains low to high erosion hazards, low to medium landslide hazards and a Category II wetland. 16. The onsite topography is generally flat. The southwest corner of the project gently slopes toward the wetland. The remaining portion of the site drains into the roadside ditch along SR 169. 17. Approximately 9,000 cubic yards of material would be cut onsite and approximately 20,000 cubic yards of fill is proposed to be brought to the site. 18. The applicant is proposing to begin plat infrastruture construction in 2016-2017. 19. Staff received four (4) public comment letters or emails (Exhibits 30-33). To address public comments the following report contains analysis related to development, traffic, access, and noise walls. 20. Staff received agency comments from Washington State Historic Preservation Officer and Department of Archaeology and Historic Preservation requesting an archaeology-survey (dated July 5, 2016; Exhibit 26). 21. Staff received agency comments from Muckleshoot Indian Tribe Fisheries Division Habitat Program on May 12, 2015 regarding wetland mitigation from parcel 3423059202 with respect to the Lennon Critical Areas Alternation Exception Project (CAEX14-0008) (Exhibit 34). Lennon Investments, Inc. intends to complete the mitigation for CAEX14-0008 in Tract H. 22. Pursuant to the City of Renton's Environmental Ordinance and SEPA (RCW 43.21C, 1971 as amended), on July 11, 2016 the Environmental Review Committee issued a Determination of Non-Significance - Mitigated (DNS-M) for the Elliott Farms Preliminary Plat (Exhibit 35). The DNS-M included six (6) mitigation measures. A 14-day appeal period commenced on July 15, 2016 and ended on July 29, 2016. No appeals of the threshold determination have been filed as of the date of this report. 23. Based on an analysis of probable impacts from the proposal, the Environmental Review Committee (ERC) issued the following mitigation measures with the Determination of Non-Significance – Mitigated: a. Project construction shall be required to comply with the recommendations found in the Geotechnical Engineering Study prepared by Terra Associates, Inc. dated February 25, 2015 or an updated report submitted at a later date. b. The applicant shall remove the existing concrete foundation(s) within the wetland buffer and restore the affected areas by planting trees and shrubs within the 50-foot standard wetland buffer by hand and without heavy machinery. A tree planting plan shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. c. The applicant shall submit the final drainage report(s) used to build the Cedarwood water quality pond, including the original design, to the City of Renton Plan Reviewer prior to construction permit issuance. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 6 of 31 Hex Report d. A professional archaeological survey of the project area shall be conducted prior to ground disturbance. The results of the professional archaeological survey shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. e. If any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found, all construction activity shall stop and the owner/developer shall immediately notify the City of Renton planning department, concerned Tribes’ cultural committees, and the Washington State Department of Archeological and Historic Preservation. f. The applicant shall record a covenant on the face of the plat to vacate the plats direct public access to SR 169 when a future access to a public road can be achieved either through Molasses Creek Condominium (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. 24. A Critical Areas Report was submitted by the applicant, prepared by Raedeke Associates, Inc. on December 15, 2014 (Exhibit 11). Raedeke Associates, Inc. Soil and Wetland Scientist determined that the site contains a Category II wetland located in the southwest portion of the property. Under the vested City of Renton code, Category II wetlands must provide a standard buffer width of 50 feet. The wetland is a low-lying forested area in the southwest portion of the site. 25. Representatives from various city departments have reviewed the application materials to identify and address issues raised by the proposed development. These comments are contained in the official file, and the essence of the comments has been incorporated into the appropriate sections of this report and the Departmental Recommendation at the end of this report (Exhibit 27). 26. Comprehensive Plan Compliance: The site is designated Residential High Density (RHD) on the City’s Comprehensive Plan Map. The purpose of the RHD designation is to allow a variety of unit types, with continuity created through the application of design guidelines, the organization of roadways, sidewalks, public spaces, and the placement of community gathering places and civic amenities. The proposal is compliant with the following Comprehensive Plan Goals and Policies if all conditions of approval are met: Compliance Comprehensive Plan Analysis  Objective LU-MM: Encourage the development of infill parcels with quality projects in existing multi-family districts.  Policy LU-173. Residential Multi-family designations should be in areas of the City where projects would be compatible with existing uses and where infrastructure is adequate to handle impacts from higher density uses.  Policy LU-174. Land within the Residential Multi-family designation areas should be used to meet multi-family housing needs. Residential Multi-family designations have the highest priority for development or redevelopment with multi-family uses.  Policy LU-179. Residential Multi-Family (RMF) projects should include landscaped open space common areas for residents, and other amenities compatible with existing buildings on adjacent and abutting lots.  Policy CD-20: Orient site and building design primarily toward pedestrians through master planning, building location, and design guidelines.  Policy CD-21: In areas developed with high intensity uses, circulation within the site should be primarily pedestrian-oriented. Internal site circulation of vehicles should be separated from pedestrians wherever feasible by dedicated walkways. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 7 of 31 Hex Report  Policy CD-23: Development should have buildings oriented toward the street or a common area rather than toward parking lots. 27. Zoning Development Standard Compliance: The purpose of the Residential-14 Zone (R-14) is to encourage development, and redevelopment, of residential neighborhoods that provide a mix of detached and attached dwelling structures organized and designed to combine characteristics of both typical single family and small-scale multi-family developments. Structure size is intended to be limited in terms of bulk and scale so that the various unit types allowed in the zone are compatible with one another and can be integrated together into a quality neighborhood. Project features are encouraged, such as yards for private use, common open spaces, and landscaped areas that enhance a neighborhood and foster a sense of community. Civic and limited commercial uses may be allowed when they support the purpose of the designation. The proposal is compliant with the following development standards if all conditions of approval are met: Compliance R-14 Zone Develop Standards and Analysis  Density: The density range permitted in the R-14 zone is a minimum 7.0 up to a maximum of 14.0 dwelling units per net acre. Net density is calculated after the deduction of sensitive areas, areas intended for public right-of-way, and private access easements. Staff Comment: After factoring in all density deductions (including proposed right-of- way dedications for public streets) the site has a net square footage of 205,517 square feet or 4.6 net acres (264,409 sf – 62,892 sf = 205,517 sf). The 45-lot proposal would arrive at a net density of 9.7 dwelling units per acre (45 lots / 4.6 acres = 9.7 du/ac), which falls within the permitted density range for the R-14 zone.  Lot Dimensions: The minimum lot size permitted in the R-14 zone is 3,000 sq. ft. for detached dwellings. There is no minimum lot size for attached dwellings. A minimum lot width of 30 feet is required (40 feet for corner lots) and a minimum lot depth of 60 feet is required. The following table identifies the proposed approximate dimensions for Lots 1-45: Proposed Lot Lot Size (sq. ft.) Lot Width (feet) Lot Depth (feet) Lot 1 2,220 32 69 Lot 2 2,217 32 69 Lot 3 2,217 32 69 Lot 4 2,220 32 69 Lot 5 3,657 50 74 Lot 6 2,232 30 74 Lot 7 2,377 32 74 Lot 8 2,249 32 70 Lot 9 2,250 32 70 Lot 10 2,364 32 70 Lot 11 2,656 32 78 Lot 12 2,824 32 70 Lot 13 2,980 32 70 Lot 14 2,390 32 72 Lot 15 2,263 30 75 Lot 16 2,406 32 75 Lot 17 2,407 32 75 Lot 18 2,406 32 75 City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 8 of 31 Hex Report Lot 19 2,567 32 80 Lot 20 2,847 36 80 Lot 21 2,847 36 80 Lot 22 2,415 30 80 Lot 23 2,852 33 81 Lot 24 3,330 39 79 Lot 25 2,557 32 80 Lot 26 2,610 32 80 Lot 27 2,698 32 81 Lot 28 2,610 32 81 Lot 29 2,628 32 82 Lot 30 2,646 32 82 Lot 31 2,674 32 83 Lot 32 2,821 32 82 Lot 33 3,029 32 81 Lot 34 2,458 32 76 Lot 35 2,296 30 76 Lot 36 2,445 32 76 Lot 37 2,445 32 76 Lot 38 2,379 32 76 Lot 39 3,145 43 72 Lot 40 2,302 32 72 Lot 41 2,302 32 72 Lot 42 2,302 32 72 Lot 43 2,365 32 72 Lot 44 2,530 30 77 Lot 45 3,939 38 89 Tract A (Open Space) 43,898 N/A N/A Tract B (Alley) 1,125 N/A N/A Tract C (Alley) 2,405 N/A N/A Tract D (Open Space) 4,033 N/A N/A Tract E (Alley) 1,385 N/A N/A Tract F (Open Space) 11,396 N/A N/A Tract G (Open Space) 1,404 N/A N/A Tract H (Critical Area) 47,911 N/A N/A Staff Comment: As demonstrated in the lot dimensions table, all lots meet the requirements for minimum lot size, lot width and lot depth for attached dwellings.  Setbacks: The required setbacks in the R-14 zone are as follows: front yard is 15 feet except garages must be 20 feet, side yard is 4 feet for detached units, for attached units the side yard is 0 feet, side yard along the street 15 feet, and the rear yard is 10 feet. To ensure adequate vehicular maneuvering area, garages and carports that are accessed through alleys required a nine-foot (9’) garage door to be at least twenty six feet (26’) from the back edge of the alley or sixteen-foot (16’) garage doors must be at least twenty four (24’) from the back edge of the alley. Staff Comment: The setback requirements for the proposed lots would be verified at the time of building permit review. The proposed lots appear to contain adequate City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 9 of 31 Hex Report area to provide all the required setback areas. Compliance not yet demonstrated Building Standards: The R-14 zone has a maximum building coverage of 65% and a maximum impervious surface coverage of 80%. In the R-14 zone, a maximum residential building height of 30 feet is permitted. Staff Comment: Building height, building coverage, and impervious surface coverage for the new multi-family residences would be verified at the time of building permit review. Compliance not yet demonstrated Maximum Number of Units per Building: In the R-14 zone, no more than 6 units per building are permitted. Staff Comment: The applicant has submitted elevations and floor plans for two- and three-unit buildings. Compliance with the maximum number of units per building requirement would be reviewed at the time of building permit review. Compliant if conditions of approval are met. Landscaping: The City’s landscape regulations (RMC 4-4-070) require a 10-foot landscape strip along all public street frontages. Additional minimum planting strip widths between the curb and sidewalk are established according to the street development standards of RMC 4-6-060. Street trees and, at a minimum, groundcover, are to be located in this area when present. Spacing standards shall be as stipulated by the Department of Community and Economic Development, provided there shall be a minimum of one street tree planted per address. Any additional undeveloped right-of-way areas shall be landscaped unless otherwise determined by the Administrator. Where there is insufficient right-of-way space or no public frontage, street trees are required in the front yard subject to approval of the Administrator. A minimum of two trees are to be located in the front yard prior to final inspection for the new Single Family Residence. A fifteen-foot (15') wide partially sight-obscuring landscaped visual barrier, or ten- foot (10') wide fully sight-obscuring landscaped visual barrier, is required along common property lines when a Residential Multi-family Zone or Use Is Abutting a Less Intense Residential Zone (RMC 4-4-070F.4). Staff Comment: As proposed, the conceptual landscape plan does not include the required 10-foot wide landscaping along all street frontages according, to the Preliminary Plat and Planting Plan (Exhibit 39). The applicant would be required to include the required 10-foot wide landscaping along all street frontages, according to code. A detailed landscaping plan, complying with RMC 4-4-070, would be required to be submitted to, and approved by, the Current Planning Project Manager prior to issuance of the street and utility construction permits. A 10-foot landscape frontage is not required along the frontage of the public alley. The applicant has submitted a preliminary landscape plan (Exhibits 9 and 39) that includes a ten-foot (10') wide fully sight-obscuring landscaped visual barrier between the R-14 subject property and the abutting R-8 parcel to the south. The sight- obscuring barrier includes the following cross-section: a 6 foot (6’) high fence along the shared property line, landscaping abutting the fence, a maximum 4 foot (4’) high retaining wall, followed by additional landscaping in front of the wall. The proposed landscape plan, along Road A, also includes a 0.5-foot wide curb, an 8-foot wide planting strip, and a 5-foot wide sidewalk along approximately half of the proposed public street. A final detailed landscape plan would be reviewed for compliance with RMC prior to issuance of the street and utility construction permit issuance. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 10 of 31 Hex Report The landscaping plan proposes to plant 120 trees including, katsura, elm, flowering dogwood, Japanese snowbell, paperbark maple, vine maple, serviceberry, and cornelian cherry at either 2-inch caliper or 6-10 feet in height (Exhibits 9 and 14). Staff recommends, as a condition of approval, that the applicant install all common landscaping and open space amenities prior to plat recording. A final detailed landscape plan shall be submitted with the street and utility construction permits. The applicant is proposing 60,731 square feet of open space within four (4) tracts (Tracts A, D, F and G) throughout the subject property. All 74 significant trees in the wetland and buffer are proposed to be retained. As a condition of approval, the applicant shall create a Home Owners Association (“HOA”) that retains or improves the existing vegetation within the open space tracts. A draft HOA document has been submitted as part of the application (Exhibit 41). A final HOA shall be submitted to, and approved by, the City of Renton Current Project Manager and the City Attorney prior to Final Plat recording. Such documents shall be recorded concurrently with the Final Plat. Compliant if conditions of approval are met Tree Retention: The City’s adopted Tree Retention and Land Clearing Regulations require the retention of 20 percent of trees in a residential development. Significant trees shall be retained in the following priority order: Priority One: Landmark trees; significant trees that form a continuous canopy; significant trees on slopes greater than twenty percent (20%); Significant trees adjacent to critical areas and their associated buffers; and Significant trees over sixty feet (60') in height or greater than eighteen inches ( 18") caliper. Priority Two: Healthy tree groupings whose associated undergrowth can be preserved; Other significant native evergreen or deciduous trees; and Other significant non- native trees. Priority Three: Alders and cottonwoods shall be retained when all other trees have been evaluated for retention and are not able to be retained, unless the alders and/ or cottonwoods are used as part of an approved enhancement project within a critical area or its buffer. A minimum tree density shall be maintained on each residentially zoned lot. Lots developed with detached single family dwelling units in the R-14 zone are exempt from the minimum tree density requirements. For multi-family development, the minimum tree density is four (4) significant trees for every five thousand (5,000) square feet. The tree density may consist of existing trees, replacement trees, trees required pursuant to RMC 4-4-070F.1, Street Frontage Landscaping Required, or a combination. Staff Comment: The property is covered with a variety of trees. Several larger trees are located around the former residences at the southwest portion of the project site, including cedar, conifer, pine, spruce and alder trees (Exhibit 8). The Arborist Report identified 114 significant trees (125 including eleven 6-inch alders/cottonwoods) on the parcel proposed to be developed (Exhibit 14). Six (6) were classified as poor or dangerous, three (3) were located within private access easements/tracts, and 74 were located in critical areas and buffers. The net number of healthy trees for this development was determined to be 31. The average size of the trunk at diameter at breast height (DBH) for the surveyed trees is 14 inches (14") with the largest tree, a bigleaf maple at 60" DBH, located southwest corner of the lot in the Category II wetland (Tract H). The minimum tree retention requirement is thirty percent (20%) in City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 11 of 31 Hex Report the R-14 zone. After street and critical area deductions, the applicant is proposing to retain zero of the potential 31 healthy trees or none of the required 6 trees. The applicant is proposing to replant the subdivision with 120 new trees. These proposed onsite replacement trees exceed the minimum required replacement inches, 12 inches (12") for every tree that was unable to be retained, or 74 inches (74") for this project. Where there is insufficient ROW space or no public frontage, street trees are required in the front yard(s). A minimum tree density shall be maintained on each R-14 zoned lot. For multi-family development (attached dwelling units), the minimum tree density is four (4) significant trees for every five thousand (5,000) square feet. The tree density may consist of existing trees, replacement trees, trees required pursuant to RMC 4-4- 070F.1, Street Frontage Landscaping Required, or a combination. Compliance with tree density development standard would be would be reviewed by planning at the time of building permit review. A final tree retention and detailed landscape plan shall be submitted with the street and utility construction permits.  Parking: Parking regulations require that a minimum of two (2) parking spaces be provided for each detached dwelling. Parking regulations require that a minimum and maximum of 1.6 spaces be provided per 3 bedroom or large dwelling unit; 1.4 spaces per 2 bedroom dwelling unit; and 1.0 space per 1 bedroom or studio dwelling unit. Driveway cuts are required to be a minimum of 5 feet from property lines and new driveways may be a maximum of 16 feet in width at the property line. Maximum driveway slopes shall not exceed fifteen percent (15%); provided, that driveways exceeding eight percent (8%) shall provide slotted drains at the lower end with positive drainage discharge to restrict runoff from entering the garage/residence or crossing any public sidewalk. Staff Comment: Sufficient area exists, on each lot, to accommodate off-street vehicular parking. This is typically achieved by providing a two (2) car garage for each building (Exhibit 40). Each of the three (3) building options includes a 3 bedroom floor plan with up to two (2) garage parking stall per unit which, if rounded up, is compliant with RMC 4-4-080F.d. Compliance with individual driveway requirements would be reviewed at the time of building permit review.  Fences and Retaining Walls: In any residential district, the maximum height of any fence, hedge or retaining wall shall be seventy two inches (72"). Except in the front yard and side yard along a street setback where the fence shall not exceed forty eight inches (48") in height. There shall be a minimum three-foot (3') landscaped setback at the base of retaining walls abutting public rights-of-way. Staff Comment: The applicant is proposing a modular block wall with a maximum height of four foot (4’). The retaining walls would be constructed near the south and east property lines within the subdivision. Specifically, within the rear yards of Lots 20-32. The retaining walls have been setback a minimum of 3 feet (3') from the public right-of-way following dedication. The applicant may terrace the rear yards in order to comply with the maximum height requirements for fences, hedges and/or retaining walls. Terracing is the act of forming hillside into a number of level flat areas (terraces) between retaining walls. No portion of a retaining wall shall be measured as part of the terrace width. The width of a terrace shall be equal to the City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 12 of 31 Hex Report height of the tallest abutting retaining wall; however, the minimum terrace width shall be two feet (2') and the maximum required width shall be five feet (5'). Terrace width shall be measured from the back edge of a lower retaining wall to the foremost edge of the immediately succeeding and higher retaining wall. Terraces created between retaining walls shall be permanently landscaped with a mixture of shrubs and groundcover (trees are optional) in conformance with the standards of RMC 4-4- 070C.2.e, Landscaping. Landscaping provided in front of retaining walls and within terraces shall contribute to any landscaping required by RMC 4-4-070F. The applicant is proposing terracing behind Lots 24-28, within the required 10-foot wide fully sight obscuring landscape visual barrier, that is compliant with retaining wall height standards of the code. Details of the terracing landscape plan shall be included in the final detailed landscape plan required to be submitted with the construction permit application. No new noise walls are planned by WSDOT along the project street frontage of SR 169 (Exhibit 33). The only noise walls WSDOT has “planned” in the generally vicinity is approximately 1 mile east of the site on the north side of SR 169. This project is currently un-funded with no real time-frame for completion. 28. Design Standards: Residential Design and Open Space Standards (RMC 4-2-115) are applicable in the R-14 zone. The Standards implement policies established in the Land Use Element of the Comprehensive Plan. Compliance with Site Design Standards must be demonstrated prior to approval of the subdivision. Compliance with Residential Design Standards would be verified prior to issuance of the building permit for the new single family homes. The proposal is consistent with the following design standards, unless noted otherwise:  Lot Configuration: Developments of more than four (4) structures shall incorporate a variety of home sizes, lot sizes, and unit clusters. Dwellings shall be arranged to ensure privacy so that side yards abut other side yards (or rights-of-way) and do not abut front or back yards. Lots accessed by easements or pipestems shall be prohibited. Staff Comment: The proposal includes three different elevation variations based on the two- and three-unit buildings. Several of units have been oriented to the open space tracts so that side yards abut other side yards (or rights-of-way) and do not abut front or back yards. The scope of the project includes a lot configuration that mimics the adjacent condominium development in appearance. None of the lots would be accessed by easement and or pipestem. Compliance not yet demonstrated Garages: Garages may be attached or detached. Shared garages are also allowed, provided the regulations of RMC 4-4-080 are met. Carports are not allowed. One of the following is required; the garage must be: 1. Recessed from the front of the house and/or front porch at least eight feet (8'), or 2. Detached and set back from the front of the house and/or porch at least six feet (6'). Additionally, all of the following is required: 1. Garage design shall be of similar design to the homes, and City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 13 of 31 Hex Report 2. If sides of the garage are visible from streets, sidewalks, pathways, trails, or other homes, architectural details shall be incorporated in the design. If shared garages are allowed, they may share the structure with other homes and all of the following is required: 1. Each unit has garage space assigned to it, and 2. The garage is not to be located further than one hundred sixty feet (160') from any of the housing units to which it is assigned, and 3. The garage shall not exceed forty four feet (44') in width, and shall maintain an eight foot (8') separation from any dwellings. Staff Comment: The preliminary floor plans and elevations include a garage setback of at least eight feet (8') from the front porch. Each unit has garage space assigned and attached to the unit and the garage designs are also similar in design to the homes. Compliance for this standard would be further verified at the time of building permit review. N/A Standards for Parks: For developments that are less than ten (10) net acres: No park is required, but is allowed. For developments that are greater than ten (10) net acres: A minimum of one one- half (.5) acre park, in addition to the common open space requirement, is required. Staff Comment: The development is less than ten (10) net acres, so no park is required. Although open space, walking trails, and park amenities have been provided by the development. Compliant if conditions of approval are met Standards for Comment Open Space: Developments of four (4) or more units: Required to provide common open space as follows: 1. For each unit in the development, three hundred fifty (350) square feet of common open space shall be provided. 2. Open space shall be designed as a park, common green, pea-patch, pocket park, or pedestrian entry easement in the development and shall include picnic areas, space for small recreational activities, and other activities as appropriate. 3. Open space shall be located in a highly visible area and be easily accessible to the neighborhood. 4. Open space(s) shall be contiguous to the majority of the dwellings in the development and accessible to all dwellings, and shall be at least twenty feet (20') wide. 5. A pedestrian entry easement can be used to meet the access requirements if it has a minimum width of twenty feet (20') with a minimum five feet (5') of sidewalk. 6. Pea-patches shall be at least one thousand (1,000) square feet in size with individual plots that measure at least ten feet by ten feet (10' x 10'). Additionally, the pea-patch shall include a tool shed and a common area with space for compost bins. Water shall be provided to the pea-patch. Fencing that meets the standards for front yard fencing shall surround the pea-patch with a one foot (1') landscape area on the outside of the fence. This area is to be landscaped with flowers, plants, and/or shrubs. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 14 of 31 Hex Report 7. Grass-crete or other pervious surfaces may be used in the common open space for the purpose of meeting the one hundred fifty feet (150') distance requirement for emergency vehicle access but shall not be used for personal vehicle access or to meet off-street parking requirements. 8. Storm ponds may be used to meet the common open space requirement if designed to accommodate a fifty (50) year storm and to be dry ninety percent (90%) of the year. Staff Comment: The development includes 2.5 acres of common open space or nearly 7 times the minimum three hundred fifty (350) square feet of common open space. The common open space includes walking trails, picnic benches and pocket areas for residents. Because the open space is located throughout the development it is highly visible and is easily accessible to the neighborhood. However, the open space is lacking recreational activities for all age groups and lighting for public safety. Therefore, staff recommends, as a condition of approval, that the applicant incorporate into the landscaping plan a minimum of two (2) active play structures or courts that provide opportunities for physical exercise and social interaction and low level trail lighting. The details of these amenities shall be identified on the final landscaping plan and shall be submitted to the City of Renton Project Manager with the street and utility construction permits.  Standards for Private Yards: Developments of four (4) or more dwelling units: Each ground-related dwelling shall have a private yard that is at least two hundred fifty (250) square feet in size with no dimension less than eight feet (8') in width. An additional two hundred fifty (250) square feet of open space per unit shall be added to the required amount of common open space for each unit that is not ground related. Staff Comment: Each two-story ground unit is located on a fee simple lot that has a private yard that is two hundred fifty (250) square feet in size or greater with no dimension less than eight feet (8') in width. Compliant if Conditions of Approval are met Sidewalks, Pathways, and Pedestrian Easements: All of the following are required: 1. Sidewalks shall be provided throughout the neighborhood. The sidewalk may disconnect from the road, provided it continues in a logical route throughout the development. 2. Front yards shall have entry walks that are a minimum width of three feet (3') and a maximum width of four feet (4'). 3. Pathways shall be used to connect common parks, green areas, and pocket parks to residential access streets, limited residential access streets, or other pedestrian connections. They may be used to provide access to homes and common open space. They shall be a minimum three feet (3') in width and made of paved asphalt, concrete, or porous material such as: porous paving stones, crushed gravel with soil stabilizers, or paving blocks with planted joints. Sidewalks or pathways for parks and green spaces shall be located at the edge of the common space to allow a larger usable green and easy access to homes. 4. Pedestrian Easement Plantings: Shall be planted with plants and trees. Trees are required along all pedestrian easements to provide shade and spaced twenty feet (20') on center. Shrubs shall be planted in at least City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 15 of 31 Hex Report fifteen percent (15%) of the easement and shall be spaced no further than thirty six inches (36") on center. 5. For all homes that do not front on a residential access street, limited residential access street, a park, or a common green: Pedestrian entry easements that are at least fifteen feet (15') wide plus a five-foot (5') sidewalk shall be provided. Staff Comment: Pedestrian sidewalks and pedestrian connections are located throughout the subject property and would provide for safe and efficient pedestrian access throughout the site. In portions of the development, sidewalks have been disconnected from the road. Logical pedestrian connections are provided from SR 169 and Molasses Creek Condominiums to Road A. The applicant has included a primary 5-foot wide sidewalk along the north side of Road A and a 7-foot wide crushed rock trail throughout the open space tracts. Each portion of the trail that is directly connected to the SR 169 would be required to be paved in order to meet ADA standards. Therefore, staff recommends, as a condition of approval, that The proposed on-site seven-foot wide trail system shall be paved with concrete, except the trail system located directly behind the rear yards of Lots 34-45. The final detailed trail system and profile plans shall be submitted to the City of Renton Project Manager with the street and utility construction permits. The sidewalk and trail systems would be used to connect buildings to common open space, on-street parking, neighboring properties, and the public right-of-way (Exhibits 2, 5, 9, and 39). The front yards of Lots 1-13 abut common open space. Therefore, staff recommends, as a condition of approval, shall orient the front doors and front yards of the attached dwelling units on Lots 1-13 toward the street (Road A) or the common open space tracts. Each of these units shall provide a four foot (4’) entry walkway that connects the front entry to shared common green space trail or sidewalk system. A note to this effect shall be recorded on the face of the Plat map. Each of these units shall be designed to the highest level of architectural detailing and articulation. Sidewalks or pathways for parks and green spaces shall be located at the edge of the common space to allow a larger usable green and easy access to homes. Therefore, staff recommends, as a condition of approval, that the applicant relocate the shared common green space trail system, which runs north/south between Lots 3-18, to be located closer to the front yards of Lots 5-13 to provide more usable green space behind the lots. Lots 24-26 front Tract E (alley 1), therefore, the homes do not front on a residential access street, limited residential access street, a park, or a common green area. Therefore, a pedestrian entry easement that is at least fifteen feet (15') wide plus a five-foot (5') sidewalk shall be provided. A plat revision that is consistent with this code regulation shall be submitted to the City of Renton Project Manager with the street and utility construction permits. It appears that the applicant could shift Lots 19-23 approximately five feet (5’) to the north and incorporate a flush concrete sidewalk with the alley (alley 1) to comply with the pedestrian entry easement and sidewalk requirement of the code. Therefore, staff recommends, as a condition of approval, that the applicant submit a revised plat plan that includes a pedestrian entry easement that is at least fifteen feet (15') wide plus a five-foot (5') sidewalk to the north of Lots 24-26. Primary Entry: Both of the following are required: City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 16 of 31 Hex Report Compliant if condition of approval is met 1. The entry shall take access from and face a street, park, common green, pocket park, pedestrian easement, or open space, and 2. The entry shall include one of the following: a. Stoop: minimum size four feet by six feet (4' x 6') and minimum height twelve inches (12") above grade, or b. Porch: minimum five feet (5') deep and minimum height twelve inches (12") above grade. Exception: in cases where accessibility (ADA) is a priority, an accessible route may be taken from a front driveway. Staff Comment: Lots 1-13 all take access from the alley tracts via Road A. The current design of the 13 lots provides the lot width along the alley and the depth parallel to Road A. This type of lot design could result in a development pattern where each of these four (4) units are oriented towards the alley and not the public street (Road A) or the common open space. An orientation towards the alley would not be consistent with building design orientation toward pedestrians or the street (see Comprehensive Plan Policy CD-20 and CD-23). Therefore, staff recommends as a condition of approval, that the applicant shall orient the front doors of the units on Lots 1-13 toward the street (Road A) or the common open space tracts; in order to meet minimum primary entry standards of Residential Design and Open Space Standards (RMC 4-2-115). A note to this effect shall be recorded on the face of the Plat map. Each of these units shall be designed to the highest level of architectural detailing and articulation. Furthermore, to ensure compatibility with the remainder of the subdivision the façade modulation of these homes fronting Road A shall be designed to the highest level of architectural detailing and articulation. Including at least one articulation or change in plane of at least two feet (2’) in depth. The building designs shall be reviewed and approved at the time of building permit application. Compliance not yet demonstrated Façade Modulation: Both of the following are required: 1. The primary building elevation oriented toward the street or common green shall have at least one articulation or change in plane of at least two feet (2') in depth; and 2. A minimum one side articulation that measures at least one foot (1') in depth shall occur for all facades facing streets or public spaces. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Compliance not yet demonstrated Windows and Doors: All of the following are required: 1. Primary windows shall be proportioned vertically, rather than horizontally, and 2. Vertical windows may be combined together to create a larger window area, and 3. All doors shall be made of wood, fiberglass, metal, or glass and trimmed with three and one-half inches (3 ½") minimum head and jamb trim around the door, and 4. Screen doors are permitted, and 5. Primary entry doors shall face a street, park, common green, pocket park, or pedestrian easement and shall be paneled or have inset windows, and City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 17 of 31 Hex Report 6. Sliding glass doors are not permitted along a frontage elevation or an elevation facing a pedestrian easement. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Compliant if condition of approval is met Scale, Bulk, and Character: All of the following are required: 1. The primary building form shall be the dominating form and elements such as porches, principal dormers, or other significant features shall not dominate, and 2. Primary porch plate heights shall be one story. Stacked porches are allowed, and 3. To differentiate the same models and elevations, different colors shall be used, and 4. For single family dwellings, no more than two (2) of the same model and elevation shall be built on the same block frontage and the same model and elevation shall not be abutting. Staff Comment: The applicant has provided three (3) different building plans for the 45 units. The building plans include two-story units with either two- or three-units per building. The site plan includes in five (5) 3-unit buildings and fifteen 2-unit buildings. The 3-unit buildings are spaced out throughout the development. The models include one story porches that project out from the body of the units and units feature dark asphalt comp shingles, decorative roof brackets, board & batten siding, hardiboard siding, cedar channel siding, window glazing, shutters, and trim. The colors provided include shades of brown, tan, bronze, green, and gray. Staff recommends, as a condition of approval, that the plat shall include a minimum of four (4) different building types (models) to provide additional character to the development. The detailed floor and elevations plans shall be submitted to the City of Renton Project Manager with the street and utility construction permits. Compliant if condition of approval is met Roofs: Both of the following are required: 1. Primary roof pitch shall be a minimum six to twelve (6:12). If a gable roof is used, exit access from a third floor must face a public right-of-way for emergency access, and 2. A variety of roofing colors shall be used within the development and all roof material shall be fire retardant. Staff Comment: The applicant is proposing a 7:12 primary roof pitch for each building. However, only dark asphalt comp shingles are illustrated in the elevation details. Therefore, staff recommends, as a condition of approval, that the applicant shall submit revised building elevations and building plans to the City of Renton Project Manager with the street and utility construction permits. The roofing material shall include a variety of colors throughout the development. Compliance not yet demonstrated Eaves: The following is required: Eaves shall be at least twelve inches (12") with horizontal fascia or fascia gutter at least five inches (5") deep on the face of all eaves. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Architectural Detailing: All of the following are required: 1. Three and one-half inches (3 ½") minimum trim surrounds all windows and City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 18 of 31 Hex Report Compliance not yet demonstrated details all doors, and 2. At least one of the following architectural details shall be provided on each home: shutters, knee braces, flower boxes, or columns, and 3. Where siding is used, metal corner clips or corner boards shall be used and shall be at minimum two and one-half inches (2 ½") in width and painted. If shutters are used, they shall be proportioned to the window size to simulate the ability to cover them, and 4. If columns are used, they shall be round, fluted, or strongly related to the home's architectural style. Six inches by six inches (6" x 6") posts may be allowed if chamfered and/or banded. Exposed four inches by four inches (4" x 4") and six inches by six inches (6" x 6") posts are prohibited. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Compliant if condition of approval is met Materials and Color: All of the following are required: 1. Acceptable exterior wall materials are: wood, cement fiberboard, stucco, stone, and standard sized brick three and one-half inches by seven and one- half inches (3 ½" x 7 ½") or three and five eighths inches by seven and five- eighths inches (3 5/8" x 7 5/8"). Simulated stone, wood, stone, or brick may be used to detail homes, and 2. When more than one material is used, changes in a vertical wall, such as from wood to brick, shall wrap the corners no less than twenty four inches (24"). The material change shall occur at an internal corner or a logical transition such as aligning with a window edge or chimney. Material transition shall not occur at an exterior corner, and 3. Multiple colors on buildings shall be provided. Muted deeper tones, as opposed to vibrant primary colors, shall be the dominant colors. Color palettes for all new structures, coded to the home elevations, shall be submitted for approval. 4. Gutters and downspouts shall be integrated into the color scheme of the home and be painted, or of an integral color, to match the trim color. Staff Comment: Staff recommended under FOF 28 Residential Design and Open Space Standards: Scale, Bulk, and Character that the applicant provides a minimum of four (4) different building building types (models) to provide additional character to the development. In addition, staff recommends, as a condition of approval, that the applicant submits, to the City of Renton Current Project Manager, a site plan and a roofing materials board that identifies a variety of colors throughout the development. Compliant if condition of approval is met Mail and Newspapers: All of the following are required: 1. Mailboxes shall be clustered and located so as to serve the needs of USPS while not adversely affecting the privacy of residents; 2. Mailboxes shall be lockable consistent with USPS standard; 3. Mailboxes shall be architecturally enhanced with materials and details typical of the home's architecture; and 4. Newspaper boxes shall be of a design that reflects the character of the home. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 19 of 31 Hex Report Staff Comment: The standard United States Postal Service (USPS) mailbox would not satisfy this code requirement. The applicant would need to submit a mailbox design that is architecturally enhanced and reflects the character of the homes. Therefore, as a condition of approval, the applicant shall submit a mailbox design to be reviewed by the Current Planning Project Manager at construction permit submittal. N/A Hot Tubs, Pools, and Mechanical Equipment: Hot tubs and pools shall only be located in back yards and designed to minimize sight and sound impacts to adjoining property. Pool heaters and pumps shall be screened from view and sound insulated. Pool equipment must comply with codes regarding fencing. Staff Comment: No hot tubs or pools are proposed for Elliott Farms. Compliance not yet demonstrated Utilities: Utility boxes that are not located in alleyways or away from public gathering spaces shall be screened with landscaping or berms. Staff Comment: A final detailed landscape plan would be reviewed for compliance with RMC prior to issuance of the utility construction permit issuance. Compliance for this standard would be verified at the time of utility plan review and building permit review. Compliance not yet demonstrated Dumpster/Trash/Recycling Collection Area: Both of the following are required: 1. Trash and recycling containers shall be located so that they have minimal impact on residents and their neighbors and so that they are not visible to the general public; and 2. A screened enclosure in which to keep containers shall be provided or garages shall be built with adequate space to keep containers. Screened enclosures shall not be located within front yards. Staff Comment: Because the applicant has not identified refuse and recyclables deposit areas, it is anticipated that individual trash and recycling cans would be used for each unit. The applicant may submit a formal request for modification to staff for consideration to deviate from refuse and recyclables standards. 29. Critical Areas: Project sites which contain critical areas are required to comply with the Critical Areas Regulations (RMC 4-3-050). The proposal is consistent with the Critical Areas Regulations, if all conditions of approval are complied with:  Geologically Hazardous Areas: Based upon the results of a geotechnical report, conditions of approval for developments may include buffers and/or setbacks from buffers. A 50-foot buffer and 15-foot building setback are required from Very High Landslide Hazard Areas. Staff Comment: The Geotechnical Engineering Study identified the majority of the site as low landslide hazard (LL), defined as areas with slopes less than 15 percent. A 10- to 20-foot wide centrally-located slope aligned northwest-southeast across the site was classified as medium landslide hazard (LM) area. LM is defined as areas with slopes between 15 percent and 40 percent and underlain by soils that consist largely of sand, gravel, or glacial till. The geotechnical engineer did not observe any indications of instability, emergent groundwater seepage, significant erosion, or historical movement on or adjacent to the site in areas where soils would classify as LM. No development activity is planned in the area of the steep slope in the southwest corner of the site. Development plans would remove or regrade the centrally-located City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 20 of 31 Hex Report slope during mass regrading. The geotechnical engineer concluded that the areas to be developed on the site do not pose a risk as a landslide hazard area. N/A Streams: The following buffer requirements are applicable to streams in accordance with RMC 4-3-050G.2: Type F streams require a 115-foot buffer, Type Np streams require a 75-foot buffer, and Type Ns streams require a 50-foot buffer. An additional 15-foot building setback is required from the edge of all stream buffer areas. Staff Comment: No streams were identified in the Critical Areas Report submitted by the applicant and prepared by Raedeke Associates, Inc. (Exhibit 11). N/A Wellhead Protection Areas: Staff Comment: The site is located just outside the Wellhead Protection Area Zone 2. Compliant if condition of approval is met Wetlands: The following buffer requirements are applicable to wetlands in accordance with RMC 4-3-050M.6: Wetland Category Standard Buffer Width Category 1 100 ft. Category 2 50 ft. Category 3 25 ft. Staff Comment: A Critical Area Report was prepared by Raedeke Associates, Inc. (dated December 15, 2014; Exhibit 11) was submitted with the application materials. According to the report, there is a Category II wetland located in the southwest portion of the property. Under the vested City of Renton code, Category II wetlands must provide a standard buffer width of 50 feet. The wetland is a low-lying forested area in the southwest portion of the site. No other wetlands or critical areas were identified within the remaining portion of the property. The applicant is also providing a minimum 15-foot wide common areas tract, immediately north of the wetland buffer (Tract F), in order to provide additional separation between the wetland buffer and the proposed rear lots of Lots 34-45. Based on the provided site plan, there would be minimal impacts to the wetland and its buffer. As part of the SEPA process, a mitigation measure was included that would require the applicant to remove the existing concrete foundation(s) within the wetland buffer and restore the affected areas by planting trees and shrubs within the 50-foot standard wetland buffer by hand and without heavy machinery. 30. Compliance with Subdivision Regulations: Chapter 4-7 RMC provides review criteria for the subdivision. The proposal is consistent with the following subdivision regulations if all conditions of approval are complied with: Compliance Subdivision Regulations and Analysis  Access: Each lot must have access to a public street or road. Access may be by a shared driveway per the requirements of the street standards. The maximum width of single loaded garage driveways shall not exceed nine feet (9') and double loaded garage driveways shall not exceed sixteen feet (16'). Staff Comment: Each lot would have access to a public street, road, or alley as shown in the Preliminary Plat Plans (Exhibits 2 and 39). A new public street (Road A) would City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 21 of 31 Hex Report provide direct access to SR 169.  Blocks: Blocks shall be deep enough to allow two tiers of lots. Staff Comment: SR 169 to the north and critical area Tract H along the southwest corner of the parcel limit the depth of the subject site and the applicant’s ability to provide two tier lots. The final layout of the lots reserved the development pattern created in Molasses Creek Condominiums with homes oriented to open space.  Lots: The size, shape, orientation, and arrangement of the proposed lots comply with the requirements of the Subdivision Regulations and the Development Standards of the R-14 zone and allow for reasonable infill of developable land. Width between side lot lines at their foremost points (i.e., the points where the side lot lines intersect with the street right-of-way line) shall not be less than eighty percent (80%) of the required lot width except in the cases of (1) pipestem lots, which shall have a minimum width of twenty feet (20') and (2) lots on a street curve or the turning circle of cul-de-sac (radial lots), which shall be a minimum of thirty five feet (35'). Staff Comment: The lots are generally rectangular in shape with orientation for the maximization of views to open space. The minimum lot width in the R-14 zone is 30 feet, 80% of the lot width would be 24 feet. A majority of the lots provide a minimum frontage of 24 feet. Except for Lots 11-13 and Lot 33. Lots along street curves shall comply with the minimum standard of 24 feet as 35 feet would be wider than the minimum lot width for the zone. Therefore, staff recommends, as a condition of approval, that the applicant provide for the minimum standard of 24 feet (24’) along street curves. A final detailed site plan shall be submitted to, and approved by, the Current Planning Project Manager and the Plan Reviewer prior to construction permit approval. Compliant if modification request is approved Streets: The proposed street system shall extend and create connections between existing streets per the Street Standards outlined in RMC 4-6-060 Street Standards. Staff Comment: The proposed development fronts Maple Valley Hwy (SR 169) along the north property line. SR 169 is classified as a Principal Arterial Road and is a Washington State Highway. Primary access to the site would be provided via a new channelized public road access from SR 169 that runs through the development and connects to an existing private lane at Molasses Creek Condominiums. A street channelization plan has been reviewed and approved by Washington State Department of Transportation (WSDOT) (Exhibit 38). Adequate sight distance and frontage improvements along SR 169 would be subject to design review and approval by WSDOT. The City defers to American Association of State Highway and Transportation Officials (AASHTO) standard clear zones, which provide the same, or similar, clear zone requirements as WSDOT. This may include dedication of right-of-way (ROW) for future planned widening of SR 169 to accommodate six (6) 12-foot wide travel lanes and 8- foot wide shoulders. If curbs are used, shoulder width may be reduced to 4 feet. Existing ROW width is approximately 150 feet. Per City code 4-6-060, half-street improvements shall include a pavement width of 88 feet (44 feet from centerline), a 0.5 foot curb, an 8 foot planting strip, an 8 foot sidewalk, street trees and storm drainage improvements. However, the City’s transportation group has determined and would support an alternate standard to match the established standard street section for SR 169. The City is supportive of the developer’s request to retain the existing curb line, followed by a 6-foot wide planting strips and 5-foot wide sidewalks behind the existing curb along the project frontage of SR 169. The applicant may submit a formal request for modification to staff for consideration to deviate from the frontage improvements City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 22 of 31 Hex Report and dedication of right-of-way along SR 169. Secondary access to the lots would be available through the existing private lane to 140th Way SE and SR 169 (Exhibit 2). The subject property has easement rights to use the existing private road through Molasses Creek Condominiums (Exhibit 19). The preliminary road plans and profiles and onsite grading plan identify the existing and proposed grading and road improvements to serve the proposed 45 units (Exhibit 5). The applicant is requesting a modification from RMC 4-6-060F.2 “Minimum Design Standards Table for Public Streets and Alleys” that would modify the residential access road standard by disconnecting the majority of the public sidewalks and planter strips from the road, away from vehicular travel ways, into open space tracts throughout the development. The modified street standard includes ROW dedication between 35 feet and 53 feet along Road A. The majority of the street improvements include a paved roadway width of 20 feet with 5-foot wide sidewalks and 8-foot wide planter strips along one side of the roadway. Sidewalks and planter strips alternate between the north side of the roadway and the south side of the roadway in order to provide pedestrian access to the pathways used to connect common areas. In addition, portions of the paved road sections also include up to seven (7) on-street parking stalls along the north side of the road (Exhibit 5). See FOF 30 for more information. The proposal also includes three (3) 16-foot wide alley Tracts (Tract A (alley 3), Tract B (alley 2), and Tract E (alley 1)). Under RMC 4-6-060J, these three access tracts are identified as shared driveways. Shared driveways are not dedicated right-of-way and are owned and maintained by the Homeowner’s Association. Deviation from the shared driveway standards of the code would require a separate street modification request. The applicant may submit a formal request for modification to staff for consideration to deviate from the shared driveway standards. Alley 1 provides access to Lots 24-26, alley 2 provides access to Lots 5-13 and alley 3 provides access to Lots 1-4. Access is required within 150 feet of all points on the buildings and fire department apparatus access roadways are required to be minimum 20 feet wide fully paved, with 25 feet inside and 45 feet outside turning radius (including the turning radius to alley 2). Fire access roadways shall be constructed to support a 30 ton vehicle with 75 psi point loading. Applicant shall submit a variance request for approval by the Renton Fire Authority for 16-foot wide alley access to Lot 1- 4, 5-13 and 24-26. An earlier site plan design included a T-shaped alley that included lots without pipestems, landscape screening between the alley and the public right-of- way and minimum turning radius (Exhibit 43). Staff is more supportive of a T-shaped alley design that meets all these items. The applicant has indicated that the proposed 45-lot subdivision would generate 321 new weekday daily trips, with 27 new trips occurring during the weekday AM peak hour (5 entering, 22 exiting), and 31 new trips occurring during the weekday PM peak hour (21 entering, 10 exiting) (Exhibit 12). The estimated distribution of project traffic was based on existing traffic patterns and were generally distributed as follows: 50 percent to/from the west on SR 169; 30 percent to/from the east on SR 169; and 20 percent to/from the south on 140th Way SE. Based on the LOS results conducted at three study intersections, all intersections are expected to operate at acceptable levels (LOS D or better) during the AM and PM peak hours in 2017 with no significant impacts created by the proposed Elliott Farm. An annual growth rate of two percent was applied to the existing volumes. It is anticipated that the proposed project would result in impacts to the City’s street system. In order to mitigate transportation impacts, the applicant would be required to meet code-required frontage improvements, City of City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 23 of 31 Hex Report Renton’s transportation concurrency requirements (Exhibit 36) based upon a test of the citywide Transportation Plan and pay appropriate Transportation Impact Fees. The 2016 impact fee for condominium/townhome is $1,546.31 per dwelling unit. Based on 45 new dwelling units, the resulting impact fee would be $69,583.95 (45 X 1,546.31 per unit). Payment of transportation impact fees is applicable at the time of issuance of the building permit. The City of Renton transportation impact fee rate schedule is subject to change. All street lighting is required to meet city standards. Lighting plans were not submitted with the land use application and would be reviewed during the construction utility permit. A lighting plan and final detailed landscape plan shall be submitted to, and approved by, the Current Planning Project Manager and the Plan Reviewer prior to construction permit issuance.  Relationship to Existing Uses: The proposed project is compatible with existing surrounding uses. Staff Comment: The subject site is bordered by multi-family and single-family homes within the general vicinity of the subject property (Exhibit 3). The properties surrounding the subject site are residential low to high density and are designated RC, R-8 and R-14 on the City’s zoning map. The proposal is similar to existing development patterns in the area and is consistent with the Comprehensive Plan and Zoning Code, which encourages the development of infill parcels in existing multi-family districts. 31. Availability and Impact on Public Services: Compliance Availability and Impact on Public Services Analysis  Police and Fire: Police and Fire Prevention staff indicates that sufficient resources exist to furnish services to the proposed development; subject to the condition that the applicant provides Code required improvements and fees. Applicant would also be required to submit a variance request to reduce the width of the proposed alleys throughout the site. See FOF 28, Streets. Fire impact fees are applicable at the rate of $495.10 per single family unit. This fee is paid at time of building permit issuance.  Schools: It is anticipated that the Renton School District can accommodate any additional students generated by this proposal at the following schools: Tiffany Park Elementary School, Nelsen Middle School, and Lindbergh High School (Exhibit 29). Any new students attending the Renton schools would be bussed. The proposed project includes the installation of frontage improvements along the public street frontages, including sidewalks. The designated school bus stops are at the following intersections (at or near the project site): 14105 Maple Valley Hwy (Turn lane Molasses Creek) and 140th Way SE & SE 154th Pl. A sidewalk runs the distance from each lot to either of the designated bus stops. Therefore, there are safe walking routes to the school bus stops. A School Impact Fee, based on new single-family lots, would be required in order to mitigate the proposal’s potential impacts to the Renton School District. The fee is payable to the City as specified by the Renton Municipal Code. Currently the fee is assessed at $1,385.00 per multi-family unit.  Parks: A Park Impact Fee would be required for the future multi-family units. The current Park Impact Fee (per unit) is $1,532.56 for a 2 unit multi-family structure or $1,448.52 for a 3 to 4 unit multi-family structure. The fee in effect at the time of building permit application is applicable to this project and is payable at the time of building permit issuance. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 24 of 31 Hex Report Compliant if condition of approval is met Storm Water: An adequate drainage system shall be provided for the proper drainage of all surface water. Staff Comment: The applicant submitted a Preliminary Technical Information Report (TIR), prepared by Barghausen Consulting Engineers, Inc. (dated April 10, 2015; Exhibit 13). The 6.07-acre site is located within the Lower Cedar River drainage basin and outside the 100-year floodplain limits. According to the TIR, the project would maintain the natural discharge location for the site. However, less than 10% of the total basin area of the wetland would be diverted away from the wetland. The project’s biologist does not expect the proposed diversion would result in a substantial change in the flow available to the wetland (Exhibit 20). Based on the City’s flow control map, this site falls within the Flow Control Duration Standard, Forested Site Condition. Surface water runoff created by this development would be collected through a series of new catch basins and pipe systems in the new roadways within two (2) drainage basins. One (1) basin would be drained to the existing conveyance system in Molasses Creek and the second basin would drain to a proposed 24-inch conveyance system along the project fronting SR 169 (Exhibit 6). The proposed 45-lot subdivision is subject to full drainage review and water quality in accordance with the 2009 KCSWDM. According to the TIR, flow control is exempt for this project as the project is within a half mile of the Cedar River and direct discharge to Cedar River is permitted per City of Renton Amendment to King County Storm water design manual section 1.2.3.1, provided that the direct discharge exemption requirements, as described in the City Amendments to the 2009 KCSWDM, are met. Cedar River is listed as a Major Receiving Water and the project is less than one-half mile to the 100 year flood plain. The final Technical Information Report (TIR) must include a level 3 downstream analysis to demonstrate that there is sufficient capacity in the existing and proposed storm system and that the approval of direct discharge would not cause flooding. The developer is intending to use an existing off-site water quality facility (wetpond). The wetpond is located at the southwest corner of the SR 169 and 140th Way SE intersection. According to the TIR, the off-site water quality drainage facility (wet pond) was built and sized for several divisions of Cedarwood projects, Molasses Creek Condominium, areas of the WSDOT right-of-way, as well as the proposed Elliott Farms project. A SEPA mitigation measure was included that requires the applicant to provide a copy of the final drainage report(s) used to build the Cedarwood water quality pond by King County, including the original design of the pond. Temporary erosion and sedimentation control measures would be provided in the final engineering plan set and would be subject to the 2009 Department of Ecology Guidelines. A Construction Stormwater Permit from Department of Ecology is required if clearing and grading of the site exceeds one acre. A Stormwater Pollution Prevention Plan (SWPPP) is required for this site.  Water: The applicant has provided a water availability certificate from Cedar River Water & Sewer District (Exhibit 15). A copy of the approved water plan from Cedar River Water & Sewer District shall be provided to the City prior to approval of the Utility Construction Permit.  Sanitary Sewer: The applicant has provided a sewer availability certificate from Cedar River Water & Sewer District (Exhibit 16). A copy of the approved sewer plan from Cedar River Water & Sewer District shall be provided to the City prior to approval of the Utility Construction Permit. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 25 of 31 Hex Report 32. Site Plan Review: Pursuant to RMC 4-9-200.B, Site Plan Review is required for development in the R-14 zoning classification when it is not exempt from Environmental (SEPA) Review. Given Site Plan applications are evaluated for compliance with the specific requirements of the RMC 4-9-200.E.3 the following table contains project elements intended to comply with level of detail needed for Site Plan requests: Compliance Site Plan Criteria and Analysis Compliant if Conditions of Approval are Met a. Comprehensive Plan Compliance and consistency. Staff Comment: See previous discussion under FOF 26, Comprehensive Plan Analysis. Compliant if Conditions of Approval are Met b. Zoning Compliance and Consistency. Staff Comment: See discussion under FOF 27, Zoning Development Standard Compliance. Compliant if Conditions of Approval are Met c. Design Regulation Compliance and Consistency. Staff Comment: See discussion under FOF 28, Residential Design and Open Space Standards.  d. Planned action ordinance and Development agreement Compliance and Consistency. Staff Comment: The proposed development is compliant with Pre-Annexation Development Agreement Cedar River Lightfoot, Inc. (Exhibit 42).  e. Off Site Impacts. Structures: Restricting overscale structures and overconcentration of development on a particular portion of the site. Staff Comment: See FOF 28, Residential Design and Open Space Standards: Scale, Bulk, and Character. Circulation: Providing desirable transitions and linkages between uses, streets, walkways and adjacent properties. Staff Comment: A loop circulation system using Road A and Molasses Creek Condominium private roadway allows for local serving traffic to access the multi-family properties from SR 169 to the north. The street sections and onsite internal pathways are intended to create a pedestrian-friendly atmosphere with wide sidewalks and landscaping. Loading and Storage Areas: Locating, designing and screening storage areas, utilities, rooftop equipment, loading areas, and refuse and recyclables to minimize views from surrounding properties. Staff Comment: See FOF 27, Zoning Development Standard Compliance: Landscaping and FOF 28, Residential Design and Open Space Standards: Utilities and Dumpster/Trash/Recycling Collection Area. Views: Recognizing the public benefit and desirability of maintaining visual accessibility to attractive natural features. Staff Comment: The multi-family buildings, particularly those fronting SR 169 would provide for territorial views. Additionally, design regulations related to the height of City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 26 of 31 Hex Report proposed structures can be found in FOF 27, Zoning Development Standard: Building Standards. Landscaping: Using landscaping to provide transitions between development and surrounding properties to reduce noise and glare, maintain privacy, and generally enhance the appearance of the project. Staff Comment: See discussion under FOF 27, Zoning Development Standard: Landscaping. Lighting: Designing and/or placing exterior lighting and glazing in order to avoid excessive brightness or glare to adjacent properties and streets. Staff Comment: A lighting plan was not provided with the application; therefore staff recommended that a lighting plan be provided at the time of building permit review.  f. On Site Impacts. Structure Placement: Provisions for privacy and noise reduction by building placement, spacing and orientation. Staff Comment: The Site Plan includes an arrangement of buildings around the open space to reduce noise. Structure Scale: Consideration of the scale of proposed structures in relation to natural characteristics, views and vistas, site amenities, sunlight, prevailing winds, and pedestrian and vehicle needs. Staff Comment: The multi-family buildings would be limited to 30 feet in height. The height of the R-14 zone is consistent with the two- and three-story condominium development project completed in Phase 1. Additionally, design regulations related to the height of proposed structures can be found in FOF 27, Zoning Development Standard Compliance: Building Standards. Natural Features: Protection of the natural landscape by retaining existing vegetation and soils, using topography to reduce undue cutting and filling, and limiting impervious surfaces. Staff Comment: Approximately 9,000 cubic yards of material would be cut onsite and approximately 20,000 cubic yards of fill is proposed to be brought to the site. There is an existing Category II wetland onsite (Exhibits 1 and 11). Based on the provided site plan, there would be minimal impacts to the wetland and its buffer. Landscaping: Use of landscaping to soften the appearance of parking areas, to provide shade and privacy where needed, to define and enhance open spaces, and generally to enhance the appearance of the project. Landscaping also includes the design and protection of planting areas so that they are less susceptible to damage from vehicles or pedestrian movements. Staff Comment: See FOF 27, Zoning Development Standard Compliance: Landscaping.  g. Access Location and Consolidation: Providing access points on side streets or frontage streets rather than directly onto arterial streets and consolidation of ingress and egress points on the site and, when feasible, with adjacent properties. Staff Comment: Access would occur from the through road that connects the development from SR 169 to Molasses Creek Condominiums (Road A). The applicant is City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 27 of 31 Hex Report also proposing a 7-foot wide on-site trail system that connected to the off-site street frontage improvements along SR 169 which includes a 5-foot wide sidewalk. The wide trail system and sidewalk improvements would help to promote a walkable, pedestrian oriented, community connection that would promote safe and efficient circulation and linkages to the neighboring developments. Internal Circulation: Promoting safety and efficiency of the internal circulation system, including the location, design and dimensions of vehicular and pedestrian access points, drives, parking, turnarounds, walkways, bikeways, and emergency access ways. Staff Comment: The Site Plan proposes a through road system that creates a more logical and seamless road pattern than exists today. Pedestrian connections from the street to the buildings would be provided. See FOF 30, Compliance with Subdivision Regulations: Access and Streets. Loading and Delivery: Separating loading and delivery areas from parking and pedestrian areas. Staff Comment: The parking areas include up to seven (7) on-street parking stalls along the north side of the road (Exhibit 5). No specific loading and delivery areas are designated. The project development is residential in design. Transit and Bicycles: Providing transit, carpools and bicycle facilities and access. Staff Comment: Per RMC 4-4-080F.11.a bicycle parking spaces are required at one-half (0.5) bicycle parking space per one dwelling unit (attached dwelling). Spaces shall meet the requirements of subsection F11c of this Section, Bicycle Parking Standards. Each unit contains a garage with enough space to provide one-half (0.5) bicycle parking space per dwelling unit. Pedestrians: Providing safe and attractive pedestrian connections between parking areas, buildings, public sidewalks and adjacent properties. Staff Comment: See FOF 28, Residential Design and Open Space Standards: Sidewalks, Pathways, and Pedestrian Easements.  h. Open Space: Incorporating open spaces to serve as distinctive project focal points and to provide adequate areas for passive and active recreation by the occupants/users of the site. Staff Comment: See FOF 28, Residential Design and Open Space Standards: Standards for Comment Open Space.  i. Views and Public Access: When possible, providing view corridors to shorelines and Mt. Rainier, and incorporating public access to shorelines. Staff Comment: The proposed structures would not block view corridors to shorelines or Mt. Rainier. The public access requirement to shorelines is not applicable to the proposal.  j. Natural Systems: Arranging project elements to protect existing natural systems where applicable. Staff Comment: The site contains 47,911 SF of critical area. Other than the acknowledged Category II wetland in the southwest portion of the site, no other wetlands or critical areas were identified within the remaining portion of the property. The applicant is also providing a minimum 15-foot wide common areas tract, immediately north of the wetland buffer (Tract F), in order to provide additional City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 28 of 31 Hex Report separation between the wetland buffer and the proposed rear lots of Lots 34-45. Based on the provided site plan, there would be minimal impacts to the wetland and its buffer. See FOF 15, 24, and 29 Critical Areas.  k. Services and Infrastructure: Making available public services and facilities to accommodate the proposed use: Police and Fire. Staff Comment: Police and Fire Prevention staff indicated that sufficient resources exist to furnish services to the proposed development; if the applicant provides Code required improvements and fees. See FOF 31, Availability and Impact on Public Services: Police and Fire. Water and Sewer. Staff Comment: See FOF 31, Availability and Impact on Public Services: Water and Sanitary Sewer. Drainage. Staff Comment: See FOF 31, Availability and Impact on Public Services. Transportation. Staff Comment: Access to the site is proposed via Road A along SR 169. Increased traffic created by the development would be mitigated by payment of transportation impact fees. Currently this fee is assessed at $1,546.31 per dwelling unit. This fee increases each year and the applicable fee is paid at the time of building permit issuance. See FOF 30, Compliance with Subdivision Regulations: Streets. N/A l. Phasing: The applicant is not requesting any additional phasing. 33. Modification Analysis: The applicant is requesting a modification from RMC 4-6-060F.2 “Minimum Design Standards Table for Public Streets and Alleys” to reduce the width of the residential access roadway and relocate a fair portion of the public sidewalks and planter strips into open space tracts away from vehicular travel ways. The proposal is compliant with the following modification criteria, pursuant to RMC 4-9-250D, if all conditions of approval are met. Therefore, staff is recommending approval of the requested modification, subject to conditions as noted below: Compliance Street Modification Criteria and Analysis  a. Substantially implements the policy direction of the policies and objectives of the Comprehensive Plan Land Use Element and the Community Design Element and the proposed modification is the minimum adjustment necessary to implement these policies and objectives. Staff Comment: The proposal to develop the subject property with 45 homes is consistent with the Comprehensive Plan and zoning designations of the site. Neighborhood connectivity is facilitated by the construction of a new public road segment that would connect to the existing Molasses Creek Condominium private roadway to and from the site. The following Comprehensive Plan Objectives and Policies support development of the site as proposed with 45 units and the modified public road section:  Objective LU-FF: The project proposes urban density with efficient land utilization City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 29 of 31 Hex Report and extends a neighborhood feel of the existing neighborhood.  Policy LU-140: The project would infill with similar development adjacent to an existing development served by the connecting road system.  Policy LU-141: The project proposes a logical extension of existing development that is consistent and complimentary to the development through which it accesses. Compliant if condition of approval is met b. Will meet the objectives and safety, function, appearance, environmental protection and maintainability intended by the Code requirements, based upon sound engineering judgment. Staff Comment: The new public road segment would connect to an existing private road that serves Molasses Creek Condominiums. As a recommended condition of approval, the homeowners of the new project would enter into an agreement with the Molasses Creek Homeowner's Association for their proportionate share of maintenance of the off- site private road network. An easement already exists to extend private access through Molasses Creek Condominiums to the site. The proposed roadway would provide a paved width of 20 feet with sidewalks that are separated from the vehicle lanes for most of the length. Staff recommends, as a condition of approval that the separated sidewalks (i.e. trail system) be paved with concrete with the exception of the trail system behind the rear yards of Lots 34-45. Each townhome unit would provide up to two (2) off-street parking spaces. A final HOA shall be submitted to, and approved by, the City of Renton Project Manager and the City Attorney prior to Final Plat recording. Such documents shall be recorded concurrently with the Final Plat.  c. Will not be injurious to other property(ies) in the vicinity. Staff Comment: The connection to the existing private road was previously contemplated and an easement was created for the purpose. There is no injury to surrounding properties from the public road segment that would connect to the existing private road as the extension was previously planned and an easement exists for access from the project through Molasses Creek Condominiums. Compliant if condition of approval is met d. Conforms to the intent and purpose of the Code. Staff Comment: The intent of the Code is to have roads that can provide safe and maintainable access to development. The proposed modified public road design would conform to the need for pedestrian facilities as well as amenities such as street trees and street lighting. The public street would be dedicated to the City of Renton upon recording of the final plat. As a recommended condition of approval, public easements shall be provided for amenities that are outside of the right-of-way of the new public street. The applicant shall also provide access signage that identifies the trails system throughout the development for public access.  e. Can be shown to be justified and required for the use and situation intended; and Staff Comment: See comments under criterions ‘a’ and ‘b’.  f. Will not create adverse impacts to other property(ies) in the vicinity. Staff Comment: See comments under criterion ‘c’. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 30 of 31 Hex Report I. CONCLUSIONS: 1. The subject site is located in the Residential High Density (RHD) Comprehensive Plan designation and complies with the goals and policies established with this designation, see FOF 11 and FOF 26. 2. The subject site is located in the Residential-14 (R-14) zoning designation and complies with the zoning and development standards established with this designation provided the applicant complies with City Code and conditions of approval, see FOF 12 and FOF 27. 3. The proposed plat complies with the Residential Design and Open Space Standards provided the applicant complies with City Code and conditions of approval, see FOF 28. 4. The proposed plat complies with the Critical Areas Regulations provided the applicant complies with City Code and conditions of approval, see FOF 29. 5. The proposed plat complies with the subdivision regulations as established by City Code and state law provided all advisory notes and conditions are complied with, see FOF 30. 6. The proposed plat complies with the street standards as established by City Code, provided the project complies with all advisory notes and conditions of approval contained herein, see FOF 30. 7. There are safe walking routes to the school bus stop, see FOF 31. 8. There are adequate public services and facilities to accommodate the proposed plat, see FOF 31. 9. The proposed density and land use is anticipated to be compatible with existing and future surrounding uses, see FOF 26, FOF 27 and FOF 30. J. RECOMMENDATION: Staff recommends approval of the Elliott Farms Preliminary Plat, Site Plan Review, and Street Modification, File No. LUA15-000242, ECF, PP, SA-H, MOD, as depicted in Exhibit 2, subject to the following conditions: 1. The applicant shall comply with the mitigation measures issued as part of the Determination of Non- Significance - Mitigated, dated July 15, 2016. 2. The applicant shall install all common landscaping and open space amenities prior to plat recording. A final detailed landscape plan shall be submitted with the street and utility construction permits. 3. The applicant shall incorporate into the landscaping plan a minimum of two (2) active play structures or courts that provide opportunities for physical exercise and social interaction and low level trail lighting. The details of these amenities shall be identified on the final landscaping plan and shall be submitted to the City of Renton Project Manager with the street and utility construction permits. 4. The proposed on-site seven-foot wide trail system shall be paved with concrete, except the trail system located directly behind the rear yards of Lots 34-45. The final detailed trail system and profile plans shall be submitted to the City of Renton Project Manager with the street and utility construction permits. 5. The applicant shall orient the front doors and front yards of the attached dwelling units on Lots 1-13 toward the street (Road A) or the common open space tracts. Each of these units shall provide a four foot (4’) entry walkway that connects the front entry to shared common green space trail or sidewalk system. A note to this effect shall be recorded on the face of the Plat map. Each of these units shall be designed to the highest level of architectural detailing and articulation. 6. The applicant shall relocate the shared common green space trail system, which runs north/south between Lots 3-18, to be located closer to the front yards of Lots 5-13 to provide more usable green space behind the lots. City of Renton Department of Community & Economic Development Hearing Examiner Recommendation ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 9, 2016 Page 31 of 31 Hex Report 7. The applicant shall submit a revised plat plan that includes a pedestrian entry easement that is at least fifteen feet (15') wide plus a five-foot (5') sidewalk to the north of Lots 24-26. 8. The plat shall include a minimum of four (4) different building types (models) to provide additional character to the development. The detailed floor and elevations plans shall be submitted to the City of Renton Project Manager with the street and utility construction permits. 9. The applicant shall submit, to the City of Renton Current Project Manager, a site plan and a roofing materials board that identifies a variety of colors throughout the development. 10. The applicant shall provide for the minimum standard of 24 feet (24’) along street curves. A final detailed site plan shall be submitted to, and approved by, the Current Planning Project Manager and the Plan Reviewer prior to construction permit approval. 11. The applicant shall submit a lighting plan and final detailed landscape plan to, and approved by, the Current Planning Project Manager and the Plan Reviewer prior to construction permit issuance. 12. The applicant shall create a Home Owners Association (“HOA”) that retains or improves the existing vegetation within the open space tract and enters into an agreement with Molasses Creek Homeowner’s Association for their proportionate share of maintenance of the off-site private road network. A draft HOA document has been submitted as part of the application. A final HOA shall be submitted to, and approved by, the City of Renton Current Project Manager and the City Attorney prior to Final Plat recording. Such documents shall be recorded concurrently with the Final Plat. 13. The applicant shall provide public easements for amenities that are outside of the right-of-way of the new public street. 14. The applicant shall provide access signage that identifies the trails system throughout the development for public access. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PRELIMINARY PLAT - 1 BEFORE THE HEARING EXAMINER FOR THE CITY OF RENTON RE: Elliott Farms Preliminary Plat LUA15-000242, ECF, PP, SA-H, MOD ))))))))) DECISION UPON RECONSIDERATION SUMMARY Leland and Joanne Gregory have requested reconsideration of the approval of the above-captioned preliminary plat, issued on August 25, 2016. The Gregorys contest the location of the Elliot Farms access point to SR 169, which is located 90-100 feet from their driveway. The reconsideration request is denied and the Final Decision of the above-captioned matter is left unmodified except for the additional findings and conclusions added by this Decision Upon Reconsideration. Reconsideration is denied because the Gregorys largely or arguably entirely base their request upon assertions of error in a deviation request separately approved by City staff. The staff’s deviation decision approved a reduction in minimum separation between adjoining access points on SR 169 from Code required 330 feet to the 90-100 foot separation authorized in the Elliot Farms preliminary plat approval. Since that deviation request was not timely appealed, the examiner has no jurisdiction to review it. Even if the examiner does have jurisdiction to consider some or all of the issues raised by the Gregorys, it is determined in this Decision Upon Reconsideration that the deviation for the 90-100 foot separation was properly granted by the City and that the separation satisfies general subdivision standards requiring “adequate” streets. EXHIBITS The following exhibits are admitted and added to the administrative record as a result of the Gregory 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PRELIMINARY PLAT - 2 request for reconsideration: Ex. 49 – September 12, 2016 Jami Balint objection to Gregory Reconsideration Request Ex. 50 - First Order on Request for Reconsideration, dated September 13, 2016 Ex. 51 – September 19, 2016 Gregory Request for Reconsideration Ex. 52 - September 26, 2016 City response to reconsideration request Ex. 53 - September 30, 2016 Applicant response Ex. 54 – October 9, 2016 Gregory Reply (received by examiner 10/11/16) Ex. 55 - October 12, 2016 Applicant objection to Gregory Reply FINDINGS OF FACT Procedural: 1. Reconsideration Request Chronology. Leland and Joanne Gregory Submitted a request for reconsideration dated August 25, 2016 and received by the City on September 7, 2016. The applicant, through their attorney Jami Balint, submitted an objection dated September 12, 2016. The hearing examiner issued an order addressing the reconsideration request on September 13, 2016. The order sustained the objection in part, determining that the reconsideration request was inadmissible because it contained new evidence. The order authorized the Gregorys to resubmit their reconsideration request without new evidence by September 19, 2016. The Gregorys submitted a revised reconsideration request on September 19, 2016. The City submitted a response on September 26, 2016, the Applicant submitted a response on September 30, 2016 and the Gregorys submitted a reply on October 9, 20161. 2. Basis of Reconsideration Request. The basis of the Gregorys’ reconsideration request was that the Elliot Farms SR 169 access point was too close to their driveway. There is conflicting information in the record as to the width of the separation, but the Elliot Farms access point is most likely 90 to 100 feet from the Gregorys’ driveway. The Gregory and Elliot Farms access points adjoin each other on the south side of SR 169. The Gregorys’ reconsideration request is primarily directed at a City decision in Ex. 24 that authorizes a reduction in the minimum separation of 330 feet between the Gregory and Elliot Farms access points required by WAC 468-52-040(3)(b)(ii)(B). The Gregorys assert that the access point should be moved to one of two alleys located in Elliot Farms, which would roughly double or triple the separation between their driveway and the Elliot Farms SR 169 access point. 1 The October 9, 2016 letter objected to a reference to a conversation between the Gregorys and the applicant. That objection is sustained and the information was not considered in this reconsideration decision. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PRELIMINARY PLAT - 3 The Gregorys assert two impacts from the location of the Elliot Farms access point. They note that they currently use the south shoulder of SR 169 as a deceleration lane to enter their driveway from travelling west on SR 169 and that the approved access point eliminates this use of the shoulder. The Gregorys also assert that a new SR 169 left turn lane to be added to serve the Elliot Farms access point will restrict access to their driveway to right in/right out access. 3. Impacts of Proximate Elliot Farms Access Point. For the reasons outlined below, the approved project access point to SR 169 provides for optimal access to SR 169 from a traffic circulation and safety standpoint. The primary reason for greater separation from the Gregorys’ driveway would be to avoid the right in/right out turning restrictions on the Gregory driveway, but the circulation/safety benefits of keeping the access point in its approved location outweigh the problems caused by these turning restrictions. The Gregorys do not assert any safety impact associated with the proximity of the Elliot Farms access point and none is apparent from the record. Their primary issue is centered on the loss of shoulder use and the loss of ability to turn left due to the required installation of a left turn lane. As to the loss of shoulder use, the Gregorys do not contest the Applicant’s plausible assertion in Ex. 53 that the frontage improvements required for the project would narrow the shoulder to five feet and render it unusable as a deceleration lane no matter where the Elliot Farms SR 169 access point would be located. As a result, it is determined that the approved location of the Elliot Farms SR 169 access point is not responsible for the loss of shoulder use for deceleration. As to the impacts of the left turn lane, the Gregorys will be subjected to the same right in/right out turning restrictions onto SR 169 as the future residents of the Elliot Farms project. This is certainly an inconvenience, but the safety and/or circulation factors that were the basis for the Elliot Farms turning restrictions likely apply as well to turning movements from the Gregorys’ property, at least to a partial degree. Of course, the state would only have adopted the WAC 468-52-040(3)(b)(ii)(B) 330 foot separation requirement because of safety and/or circulation problems caused by intersections that are spaced closer together. However, the City had to balance reducing the 330 foot spacing requirement against the 2,640 foot spacing requirement between the Elliot Farms SR 169 access point and 140th Way SE, also set by WAC 468-52-040(3). The approved Elliot Farms SR 169 access point is only 2,093 feet from 140 Way SE, which is the maximum separation possible between the two access points. Due to several factors identified in Ex. 52, City staff determined that on-balance maximizing the possible separation from 140th Way SE provided for safer and more code compliant traffic circulation and improvements than adhering to the 330 foot separation required from the Gregorys’ driveway. Even eliminating grade separation issues with the adjoining Gregory property raised in the Ex. 24 deviation approval, the considerations by staff are sufficiently compelling to conclude that safety and circulation impacts are minimized by the approved location of the Elliot Farms SR 169 access point. The approved access point maximizes separation from another public road intersection (140 Way SE) and avoids the need for a cul-de-sac (which would have to be installed if the Elliot Farms SR 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PRELIMINARY PLAT - 4 169 access point were moved to one of the project’s alleys as suggested by the Gregorys). As outlined in Ex. 24 and Ex. 52, a City traffic engineer found these factors sufficient to justify a reduction to the 330 foot requirement. From a traffic circulation and safety standpoint, these factors outweigh the inconvenience of the right in/right out limitations to the Gregorys. CONCLUSIONS OF LAW 1. Authority of Examiner. The examiner has no jurisdiction to hear the validity of the City’s approval of the deviation request to WAC 468-52-040(3)(b)(ii)(B), Ex. 24, and likely has no jurisdiction to collaterally attack the approval under general road adequacy standards applicable to subdivision review. RMC 4-6-060(F)(9)(b) adopts WAC 468-51 and 468-52 (which includes the 330 foot separation requirement) by reference. RMC 4-6-060(Q)(1) provides that waivers from WAC 486-52 are subject to the criteria of RMC 4-9-250. Ex. 24 does not clearly identify the approved deviation as processed pursuant to RMC 4-9-250, but in the absence of any evidence to the contrary City staff are presumed to use review procedures authorized by City code. RMC 4-8-080(G) provides that deviation/modification decisions are subject to appeal to the hearing examiner. RMC 4-8-110(C)(3) requires appeals to be filed with the examiner within 14 days of issuance of the decision appeal. No timely appeal was filed of the Ex. 24 deviation approval. In the absence of a timely appeal, a permit decision, even if noncompliant with permitting criteria, can no longer be challenged. See Nykreim Chelan County v. Nykreim, 146 Wn.2d 904 (2002). Further, case law is clear that cities cannot collaterally revisit permitting decisions in subsequent permit applications. See Habitat Watch v. Skagit County, 155 Wn.2d 397 (2005). The courts are equally clear that a permit decision cannot be revisited even though no notice of the decision is provided to the public. Durland v. San Juan County, 182 Wn.2d 55 (2015)(fact that neighbor did not receive notice of building permit did not relieve neighbor of requirement to file an administrative appeal within time limits set by County code). Given these parameters, it is clear that the Ex. 24 deviation approval cannot be revisited in the Gregorys’ reconsideration request. It is also likely that applying general subdivision criteria to address the adequacy of the separation (specifically, the criterion requiring “adequate” roads, RMC 4-7-080(B)(4)) would be considered a collateral attack on the Ex. 24 deviation approval. Nonetheless, in case on appeal the examiner is determined to have jurisdiction, applicable deviation and subdivision standards will be addressed in this decision. 2. Approved Gregory/Elliot Farms Separation Complies with Applicable City Standards. The approved 90-100 separation between the Gregory driveway and Elliot Farms SR 169 access point both satisfies the criteria for a deviation and the adequacy standard of RMC 4-7- 080(B)(4). The access point provides for “adequate” streets as required by RMC 4-7-080(B)(4) because the approved access point is an optimal location in terms of safety and circulation efficiency for the reasons outlined in Finding of Fact No. 3. The Ex. 24 deviation request is governed by the standards of RMC 4-9-250(D)(2) and is consistent with all of them. As required by RMC 4-9-250(D)(2), strict adherence to the separation requirements of WAC 468-52-040(3)(b)(ii)(B) is impractical, given that two access points are 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PRELIMINARY PLAT - 5 necessary for the project and further separation from the Gregory driveway would require closer proximity to 140th Way SE, which is prohibited by the code, while at the same time necessitating a cul-de-sac, which is strongly discouraged by the code. Given the balancing of factors outlined in Finding of Fact No. 3, the separation deviation is the minimum deviation necessary to implement the safety and circulation objectives of the comprehensive plan as required by RMC 4-9-250(D)(2)(a). Further, for the reasons outlined in Finding of Fact No. 3, the deviation meets the objectives and safety, function, appearance, environmental protection and maintainability intended by the Code requirements, based upon sound engineering judgment as required by RMC 4-9-250(D)(2)(b). As further determined in Finding of Fact No. 3, the proposal would not be injurious to other properties as required by RMC 4-9-250(D)(2)(c), as the primary impact on the Gregorys will be right in/right out turn restrictions, which may actually serve to enhance their safety. Since the proposed access points optimize safety and circulation efficiency, the approved access point is consistent with the intent and purpose of the Code as required by RMC 4-9-250(D)(2)(d). Finally, for the reasons identified in making strict compliance with separation requirements impractical, the deviation is shown to be justified for the use and situation intended as required by RMC 4-9-250(D)(2)(e). DECISION Reconsideration is denied for the reasons outlined in this decision. The August 25, 2016 Final Decision of the above captioned matter is to remain unchanged, except that the findings and conclusions of this Decision Upon Reconsideration should be considered as supplemental to the Final Decision. DATED this 25th day of October, 2016. City of Renton Hearing Examiner APPEAL RIGHTS AND VALUATION NOTICES RMC 4-8-080(G) provides that the final decision of the hearing examiner is subject to appeal to the Renton City Council. RMC 4-8-110(E)(14) requires appeals of the hearing examiner’s decision to be filed within fourteen (14) calendar days from the date of the hearing examiner’s decision. Additional information regarding the appeal process may be obtained from the City Clerk’s Office, Renton City Hall – 7th floor, (425) 430-6510. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PRELIMINARY PLAT - 6 Affected property owners may request a change in valuation for property tax purposes notwithstanding any program of revaluation. DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT ERC Report LUA15-000242 ENVIRONMENTAL REVIEW COMMITTEE REPORT ERC MEETING DATES: August 31, 2015, September 14, 2015 and July 11, 2016 Project Name: Elliott Farms Preliminary Plat Project Number: LUA15-000242, ECF, PP, SA-H, MOD Project Manager: Clark H. Close, Senior Planner Owner: Lennon Investments, Inc. 35815 SE David Powell Road, Fall City, WA 98024 Owner: Cedar River Lightfoot, Inc. 14410 Bel-Red Road, Suite 200, Bellevue, WA 98007 Applicants: Patrick O. Lennon and Todd Levitt 35815 SE David Powell Road, Fall City, WA 98024 14410 Bel-Red Road, Suite 200, Bellevue, WA 98007 Contact: Ivana Halvorsen, Barghausen Consulting Engineers, Inc. 18215 - 72nd Ave S, Kent, WA 98032 Project Location: SR 169 East of 140th Way SE (APN 222305-9004) Project Summary: The applicant is requesting Preliminary Plat, Hearing Examiner Site Plan, SEPA Environmental Review approval and a Street Modification for a 45-lot subdivision for the future construction of attached two- and three-unit buildings. The 6.07- acre site is located along SR-169 between 140th Way SE and 145th Ave SE within the Residential-14 zoning district (APN 2223059004). On June 16, 2016, the applicant submitted revised plat plan that would divide the parcel into 45 residential lots and 8 tracts that would result in a net density of 9.7 dwelling units per acre. The tracts include 47,911 square feet (SF) of critical areas, 60,731 SF of open space and 4,915 SF for alleys. The proposed fee simple lots would range in size from 2,217 SF to 3,939 SF with an average lot size of 2,586 SF. Primary access to the development would be via a managed public road access from Maple Valley Highway (SR 169) that runs through the development and connects to an existing private lane at Molasses Creek Condominiums (MCC). Secondary access to the lots would be available through the existing private road due to the existing private easement through MCC. The scope of the project is to mimic the adjacent condominium development as contemplated by the Pre-Annexation Agreement and Aqua Barn Annexation in 2008. The site is currently undeveloped and contains moderate landslide hazards and a Category II wetland with a 50-foot buffer. The site is in the Cedar River drainage basin and outside the 100-year floodplain limits. Stormwater will be conveyed to the existing water quality pond that was constructed as part of the Plat of Elliott Farms and MCC, located west of 140th Way SE. Soils consist of Newburg Silt Loam (Ng) with a small area of Alderwood and Kitsap (AkF). Approximately 9,000 cubic yards of cut would spread on the finished lots City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 2 of 13 ERC Report 15-000242 and/or exported off-site and approximately 20,000 cubic yards of fill material would be imported for the project. The site contains 114 significant trees. The project will remove 31 viable evergreen and deciduous trees within the development area. All 74 significant trees in the wetland and buffer will remain. The project will replant 97 trees onsite. The applicant has submitted a Critical Area Report, Technical Information Report, Traffic Impact Assessment, Arborist Report, Wetland Delineation, Letter of Understanding of Geologic Risk, and a Geotechnical Engineering Study with the application. Site Area: 264,409 SF (6.07 acres) STAFF RECOMMENDATION: Staff Recommends that the Environmental Review Committee issue a Determination of Non-Significance - Mitigated (DNS-M). Project Location Map: PART ONE: PROJECT DESCRIPTION / BACKGROUND The applicant is requesting Preliminary Plat approval and Environmental (SEPA) Review for the subdivision of a 6.07-acre parcel located on the south side of SR 169, between 140th Way SE and 145th Ave SE, within the SE ¼ of Section 22, Township 23 North, Range 05 East, W.M. (Exhibits 2 & 3). The specific address assigned to this parcel is 14207 Maple Valley Hwy LOT, Renton, WA 98058 (Parcel No. 2223059004). The site contains no existing structures, but there are remnants from past uses. Upon completion of the project, all existing vegetation within the developable portion of the property would either be removed or altered. The site is proposed to be subdivided into 45 single family residential lots, associated improvements, a modified limited residential access street (with utilities), and a critical area tract located at the southwest corner of the site (Exhibits 2, 7 & 9). An off-site water quality facility was previously constructed to accommodate the project (Exhibit 13). The subject site fronts Maple Valley Highway (SR 169). Maplewood Golf Course and Ron Regis Park are located across SR 169 or to the north of the project site. The MCC site is located immediately to the west City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 3 of 13 ERC Report 15-000242 of the project. A single family residential development, known as Pioneer Place, is located to the east and a single family home, Gregory residence, is located to the south. Table 1. Land Use and Zoning (Project vesting date May 5, 2015) Location Comprehensive Land Use Zoning Site Residential High Density (RHD) Residential-14 Dwelling Units per Net Acre (R-14) Table 2. Surrounding Land Use and Zoning (Effective date July 1, 2015) Location Comprehensive Land Use Zoning North Residential Low Density (RLD) Resource Conservation (RC) South Residential Medium Density (RMD); Residential Low Density (RLD) Residential-8 Dwelling Units per Net Acre (R-8); Resource Conservation (RC) East Residential Medium Density (RMD) Residential-8 Dwelling Units per Net Acre (R-8); West Residential High Density (RHD); Residential Low Density (RLD) Residential-14 Dwelling Units per Net Acre (R-14); Resource Conservation The project site is located within the Residential - 14 (R-14) dwelling units per net acre zoning classification. The net density of the project is 8.3 dwelling units per net acre (45 / 4.63 net acres = 9.7 du/acre) and the 45 lots would range in size from 2,217 SF to 3,939 SF with an average lot size of 2,586 SF (Exhibit 2). The site contains 47,911 SF of critical area and 34,665 SF of public street area. The net lot area is 4.63 acres. The project includes approximately 1,035 lineal feet of public roadway (with utilities) constructed to serve the proposed lots and 692 lineal feet of frontage improvements on SR 169. A channelized intersection near the northeast property line would provide direct public access from the development to SR 169 as a right-in/right-out access. The public road would connect to an existing private access easement in MCC to the west. The project would develop the site with 45 fee simple lots with 45 townhomes that are attached in two- and three-unit buildings. The scope of the project is designed to mimic the adjacent condominium development to the west and would include alley-loaded and front-loaded product. The density of the project has been capped at 45 units, based on the 2008 Pre-Annexation Development Agreement, which is consistent with the R-14 zoning regulations (Exhibit 18). Each lot would contain a three bedroom townhome and have a two car garage and 250 SF of common open space. In addition, approximately seven (7) on-street parallel parking stalls, 4,915 SF of alley use, and approximately 60,731 SF (1.4 acres) of open space. Trails, picnic tables, benches and landscaping would also be provided throughout the plat. The site was formerly occupied by a working dairy farm with a residence and garage on the west side of the property and several barns and structures located on the south side of the site. All buildings and structures have been demolished. The only evidence of the former structures is the remaining concrete foundations and floor slabs from both the residence and barns. The ground cover consists primarily of weeds, grass, and brush. Ground cover on the western and southern portions of the site includes a forested area of small to medium growth trees. Residential LED street lighting would be provided throughout the plat. Road improvements would be completed on SR 169, including curb, gutter, sidewalk, and planter strip. With regards to the design clear zone, given the posted speed of 50 mph along this section of SR-169, the City defers to American Association of State Highway and Transportation Officials (AASHTO) standard clear zones, which provide the same or similar clear zone requirements as the Washington State Department of Transportation (WSDOT). WSDOT Design Manual Section 1600.03(2)(a) Roadside and Median would preclude the City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 4 of 13 ERC Report 15-000242 developer from installing street trees and street lighting along the frontage of SR-169 as part of the development (Exhibit 25). The on-site topography is generally flat. The southwest corner of the project gently slopes toward the wetland. The remaining portion of the site drains into the roadside ditch along WA-169, where it is conveyed westerly to the existing water quality drainage facility, then to the Cedar River (Exhibits 4 & 6). There is an existing drainage ditch along the east side of the project that conveys off-site upstream flows from the southeast. The elevations on the site range from 107 to 87. Approximately 9,000 cubic yards of cut would spread on the finished lots and/or exported off-site and approximately 20,000 cubic yards of fill material would be imported for the project. The proposed drainage system for this project is subject to the requirements of the 2009 King County Surface Water Design Manual (KCSWDM)1, and the 2010 City of Renton Amendments to the KCSWDM. The project would discharge flows to the Cedar River, which is listed as a Major Receiving Water in the 2009 KCSWDM. As part of the improvements, the applicant is seeking to retain 74 trees within the wetland and wetland buffer tract. The project is proposing to remove 31 viable trees within the development area (Exhibit 8), and the property’s vegetation consists of dense brambles and 114 significant trees (Exhibit 14). The project would replant 97 trees onsite (Exhibit 9). The Natural Resources Conservation Service has classified the majority of the site soils as Newburg Silt Loam (Ng) having a slight potential for erosion. The southwestern corner of the site was classified as Alderwood and Kitsap soils with a severe potential for erosion. No development is proposed within the wetland and wetland buffer located at the southwest corner of the site. A geotechnical study found the presence of organic soils up to 12 inches, followed by glacially-derived or alluvial soils (Exhibit 10). The site is served by Cedar River Water and Sewer District (Exhibits 15 & 16). PART TWO: ENVIRONMENTAL REVIEW In compliance with RCW 43.21C.240, the following environmental (SEPA) review addresses only those project impacts that are not adequately addressed under existing development standards and environmental regulations. A. Environmental Threshold Recommendation Based on analysis of probable impacts from the proposal, staff recommends that the Responsible Officials: Issue a DNS-M with a 14-day Appeal Period. B. Mitigation Measures 1. Project construction shall be required to comply with the recommendations found in the Geotechnical Engineering Study prepared by Terra Associates, Inc. dated February 25, 2015 or an updated report submitted at a later date. 2. The applicant shall remove the existing concrete foundation(s) within the wetland buffer and restore the affected areas by planting trees and shrubs within the 50-foot standard wetland buffer by hand and without heavy machinery. A tree planting plan shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. 1 2009 King County Surface Water Manual and the 2009 City of Renton Amendments to the KCSWM, Chapter 1 and 2. City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 5 of 13 ERC Report 15-000242 3. The applicant shall submit the final drainage report(s) used to build the Cedarwood water quality pond, including the original design, to the City of Renton Plan Reviewer prior to construction permit issuance. 4. A professional archaeological survey of the project area shall be conducted prior to ground disturbance. The results of the professional archaeological survey shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. 5. If any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found, all construction activity shall stop and the owner/developer shall immediately notify the City of Renton planning department, concerned Tribes’ cultural committees, and the Washington State Department of Archeological and Historic Preservation. 6. The applicant shall record a covenant on the face of the plat to vacate the plats direct public access to SR 169 when a future access to a public road can be achieved either through Molasses Creek Condominium (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. C. Exhibits Exhibit 1 ERC Report Exhibit 2 Elliott Farms Preliminary Plat Plan (with Cover Sheet) Exhibit 3 Neighborhood Detail Map Exhibit 4 Boundary & Topography Survey (Sheets 1 & 2) Exhibit 5 Preliminary On-Site Road Plans and Profiles Exhibit 6 Preliminary Onsite Grading and Drainage Plan Exhibit 7 Preliminary Utility Plan Exhibit 8 Preliminary Tree Inventory and Clearing Plan Exhibit 9 Preliminary Planting Plan and Planting Schedule Exhibit 10 Geotechnical Engineering Study prepared by Terra Associates, Inc. (dated February 25, 2015) Exhibit 11 Critical Area Report prepared by Raedeke Associates, Inc. (dated December 15, 2014) Exhibit 12 Traffic Assessment prepared by Transportation Engineering Northwest (TENW) (dated April 1, 2015; revised date December 11, 2015) Exhibit 13 Technical Information Report prepared by Barghausen Consulting Engineers, Inc. (dated April 10, 2015) Exhibit 14 Arborist Report prepared by Greenforest Incorporated (dated April 1, 2015) Exhibit 15 Certificate of Water Availability (dated February 24, 2015) Exhibit 16 Certificate of Sewer Availability (dated February 24, 2015) Exhibit 17 Construction Mitigation Description Exhibit 18 Pre-Annexation Agreement with Cedar River Lightfoot Inc. (public hearing date April 21, 2008) Exhibit 19 Private Easement Agreement through Molasses Creek Condominiums (Recording No. 20000201000940) Exhibit 20 Technical Memorandum prepared by Raedeke Associates, Inc. (dated September 8, 2015) Exhibit 21 Wetland Drainage Area Map Exhibit 22 Channelization Plan Exhibit 23 Channelization Detail (Right In – Right Out) City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 6 of 13 ERC Report 15-000242 Exhibit 24 SR 169 Access Spacing Deviation Determination (dated May 12, 2016) Exhibit 25 SR 169 Design Clear Zone Letter (dated June 2, 2016) Exhibit 26 Archaeology-Survey Requested by Washington State Historic Preservation Officer and Department of Archaeology and Historic Preservation (dated July 5, 2016) Exhibit 27 Advisory Notes to Applicant D. Environmental Impacts The Proposal was circulated and reviewed by various City Departments and Divisions to determine whether the applicant has adequately identified and addressed environmental impacts anticipated to occur in conjunction with the proposed development. Staff reviewers have identified that the proposal is likely to have the following probable impacts: 1. Earth Impacts: A Geotechnical Engineering Study prepared by Terra Associates, Inc. (dated February 25, 2015; Exhibit 10) was submitted with the project application. According to the submitted study, the existing site topography in the north-northeast portion of the site is flat. The southwest corner of the project gently slopes toward the wetland and the project site has an average slope of approximately two percent (2%). The remaining portion of the site drains generally toward the wetland. The remaining portion of the site drains into the roadside ditch along SR 169. A field exploration by Terra Associates, Inc. indicated that the site is generally underlain by 6 to 12 inches of organic surface soils and roots overlying either glacially-derived or alluvial soils. Glacially-derived soils are found on roughly the southwestern half of the site and consist of loose to very dense sand with silt and gravel, dense gravel with cobbles, and medium stiff to very stiff sandy silt (outwash and undifferentiated drift). Alluvial soils are found on roughly the northeastern half of the site and consist of three to five feet of loose silty sand and soft silt overlying dense gravel with sand and cobbles. The glacial and alluvial soils have low permeability and would not be a suitable receptor soil for discharge of development stormwater using infiltration/retention facilities. Groundwater was observed in 5 of the 8 test pits between 4.5 and 6 feet below current site grades. Based on current topography, the applicant is expecting cuts and fills up to ten feet may be needed to establish lot and roadway grades. Approximately 9,000 cubic yards of cut and 20,000 cubic yards of fill would be imported for the project from an approved fill source to support 45 two-story fee simple townhouse units and associated plat improvements. The on-site strippings (topsoil) would either be spread on the finished lots and/or exported off-site to an approved location. A rockery retaining wall, ranging between two and four feet, would be constructed along the southeast corner of the site. Temporary erosion and sedimentation control measures would be implemented during construction (Exhibit 17). Vegetation consists primarily of weeds, grass, brush and a variety of trees. Most of the significant trees stand along the south and western areas, and are mostly within the wetland and wetland buffer, or a steep slope at the southwest corner of the site. Red alder, Bigleaf maple, Western red- cedar, and Scouler’s willow make up the majority of the trees onsite in size and quantity (Exhibits 4, 8, 9 & 14). Other tree species on the site include Douglas-fir, Western hemlock, Moss cypress, Spanish fir, Pine, Black cottonwood, English holly, and Norway spruce. The applicant has identified 114 significant trees onsite. One (1) tree was classified as dead and 21 were determined as defect trees. All existing trees in development area would be removed for infrastructure, homes and safety. Whereas, all 74 trees within the wetland and wetland buffer would be retained. City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 7 of 13 ERC Report 15-000242 A total of eight (8) test pits (TP-1 through TP-8) were excavated across the project site to a maximum depth of 15 feet below existing site grades using a track hoe. Seepage generally occurred within the gravel encountered at depths of about five feet. No groundwater was found in Test Pits TP-5, TP-6, or TP-7. Groundwater levels are expected to vary on a seasonal and annual basis. According to the geotechnical engineer, construction of the proposed residential development is suitable from a geotechnical standpoint. The proposed residential buildings can be supported on conventional spread footings bearing on competent native soils or on structural fill placed on competent native soils. Floor slabs and pavements can be similarly supported. Some of the native glacial and alluvial deposits encountered at the site contain a sufficient amount of fines (silt- and clay-sized particles) that would make compaction to structural fill requirements difficult or impossible when the soils are too wet. Site preparation activities would involve removal of existing foundations, site clearing and stripping, and implementation of temporary erosion control measures. After completion of site stripping and rough grading activities, Terra Associates recommends a proofroll using heavy rubber-tired equipment to determine if any isolated soft and yielding areas are present. If excessively yielding areas are observed, and they cannot be stabilized in place by compaction, the affected soils should be excavated and removed to firm bearing and grade restored with new structural fill. If the depth of excavation to remove unstable soils is excessive, the use of geotextile fabrics could be used in conjunction with clean granular structural fill beneath embankment of fills or roadway subgrades. The submitted geotechnical report provides recommendations for site preparation and grading, excavation and slopes, foundations, slab-on-grade floors, lateral earth pressure for below-grade walls, drainage, utilities, and pavement sections. Staff recommends as a SEPA mitigation measure that project construction be required to comply with the recommendations found in the Geotechnical Engineering Study prepared by Earth Solutions, NW (dated October 29, 2014) or an updated report submitted at a later date. Mitigation Measure(s): Project construction shall be required to comply with the recommendations found in the Geotechnical Engineering Study prepared by Terra Associates, Inc. (dated February 25, 2015; Exhibit 10) or an updated report submitted at a later date. Nexus: State Environmental Policy Act (SEPA) Environmental Review, RMC 4-4-060 Grading, Excavation and Mining Regulations, and RMC 4-3-050 Critical Areas Regulations. 2. Water a. Wetlands, Streams, Lakes Impacts: A Critical Area Report was prepared by Raedeke Associates, Inc. (dated December 15, 2014; Exhibit 11) was submitted with the application materials. According to the report, there is a Category II wetland located in the southwest portion of the property. Under the vested City of Renton code, Category II wetlands must provide a standard buffer width of 50 feet. The wetland is a low-lying forested area in the southwest portion of the site. Vegetation in the wetland area is comprised of a red alder canopy over a salmonberry and Himalayan blackberry shrub layer. Field horsetail and creeping buttercup are the dominant species identified in the herbaceous layer. The majority of the species observed were rated facultative or wetter (Reed 1988), so the vegetation community would be considered hydrophytic, per the COE (2010) guidelines. Soils observed in the wetland were very dark grayish brown (10YR 3/2) silt loam over gray (10YR 5/1) and dark grayish brown (10YR 4/2) silt loams. The deeper soil profiles exhibited many City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 8 of 13 ERC Report 15-000242 redoximorphic features (mottles), and dark soils with mottles are positive indicators of hydric (wetland) soils. The soil and wetland scientist encountered a water table at 18 inches below the ground surface during June field investigations conducted in 2012.Other than the acknowledged Category II wetland in the southwest portion of the site, no other wetlands or critical areas were identified within the remaining portion of the property. Additionally, there are no observed or known state or federally listed species utilizing the site or near the site. The applicant is also providing a minimum 15-foot wide common areas tract, immediately north of the wetland buffer (Tract F), in order to provide additional separation between the wetland buffer and the proposed rear lots of Lots 34-45. Based on the provided site plan, there would be minimal impacts to the wetland and its buffer. The applicant submitted a Technical Memorandum, prepared by Raedeke Associates, Inc. (dated September 8, 2015; Exhibit 20) in order to review the potential hydrologic impacts to the wetland on the site resulting from the development. The wetland lies within an approximately 7.2 acre basin. Site development would divert drainage from 0.4 acres of the basin away from the wetland, representing approximately 5.6% of the total contributing area. The hydrologic support provided to the wetland from this portion of the basin is likely greatest during the wetter months of the year and it is likely that the majority of the hydrologic input to the wetland is derived from the steeply sloping ground to the south and west of the wetland and that the relatively flat area to the north and east of the wetland contributes a much smaller volume of water. On March 9, 2015, the site was approved with two (2) conditions by the City of Renton for an exemption from the Critical Areas Regulations in order to conduct wetland and wetland buffer enhancement activities (LUA15-000120). The enhancement project provides off-site mitigation for construction impacts associated with King County parcel no. 3423059202, under King County project number CAEX14-0008. King County conducted SEPA review and acted as lead SEPA agency and King County Department of Permitting and Environmental Review reviewed this parcel for off- site mitigation and consistency with King County Code 21A.24. The project, if carried forward, would enhance 5,110 square feet of the Category II wetland and 6,225 square feet of wetland buffer. The work plan includes removing an existing concrete foundation, removing non-native vegetation from the subject areas, and planting native trees and shrubs. The purpose of the plan was to enhance the structural and vegetative diversity on the site, leading to an increase in habitat and overall functional lift over existing conditions. Should the applicant elect to not move forward with the permitted wetland and wetland buffer enhancement activities, staff recommends, as a SEPA mitigation measure, that the applicant remove the existing concrete foundation(s) within the wetland buffer and restore the affected areas by planting trees and shrubs within the 50-foot standard wetland buffer by hand and without heavy machinery. Mitigation Measure(s): The applicant shall remove the existing concrete foundation(s) within the wetland buffer and restore the affected areas by planting trees and shrubs within the 50-foot standard wetland buffer by hand and without heavy machinery. A tree planting plan shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. Nexus: State Environmental Policy Act (SEPA) Environmental Review and RMC 4-3-050 Critical Areas Regulations. b. Storm Water City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 9 of 13 ERC Report 15-000242 Impacts: The applicant submitted a Preliminary Technical Information Report (TIR), prepared by Barghausen Consulting Engineers, Inc. (dated April 10, 2015; Exhibit 13). The 6.07-acre site is located within the Lower Cedar River drainage basin and outside the 100-year floodplain limits. According to the TIR, the project would maintain the natural discharge location for the site. However, less than 10% of the total basin area of the wetland will be diverted away from the wetland. The project’s biologist does not expect the proposed diversion would result in a substantial change in the flow available to the wetland (Exhibit 20). Based on the City’s flow control map, this site falls within the Flow Control Duration Standard, Forested Site Condition. Surface water runoff created by this development would be collected through a series of new catch basins and pipe systems in the new roadways within two (2) drainage basins. One (1) basin would be drained to the existing conveyance system in Molasses Creek and the second basin would drain to a proposed 24-inch conveyance system along the project fronting WA-169 (Exhibit 6). The proposed 45-lot subdivision is subject to full drainage review and water quality in accordance with the 2009 KCSWDM. According to the TIR, flow control is exempt for this project as the project is within a half mile of the Cedar River and direct discharge to Cedar River is permitted per City of Renton Amendment to King County Storm water design manual section 1.2.3.1, provided that the direct discharge exemption requirements, as described in the City Amendments to the 2009 KCSWDM, are met. The Cedar River is listed as a Major Receiving Water and the project is less than one-half mile to the 100 year flood plain. The final Technical Information Report (TIR) must include a level 3 downstream analysis to demonstrate that there is sufficient capacity in the existing and proposed storm system and that the approval of direct discharge would not cause flooding. The developer is intending to use an existing off-site water quality facility (wetpond). The wetpond is located at the southwest corner of the WA 169 and 140th Way SE intersection. According to the TIR, the off-site water quality drainage facility (wet pond) was built and sized for several divisions of Cedarwood projects, MCC, areas of the WSDOT right-of-way, as well as the proposed Elliott Farms project. Staff recommends, as a SEPA mitigation measure, that the applicant provide a copy of the final drainage report(s) used to build the Cedarwood water quality pond by King County. The report should include the original design of the pond. Temporary erosion and sedimentation control measures would be provided in the final engineering plan set and would be subject to the 2009 and Department of Ecology Guidelines. A Construction Stormwater Permit from Department of Ecology is required if clearing and grading of the site exceeds one acre. A Stormwater Pollution Prevention Plan (SWPPP) is required for this site. Mitigation Measure(s): The applicant shall submit the final drainage report(s) used to build the Cedarwood water quality pond, including the original design, to the City of Renton Plan Reviewer prior to construction permit issuance. Nexus: RMC 4-6-030 Drainage (Surface Water) Standards 3. Trees and Vegetation Impacts: The property is covered in weeds, grass, brush and a variety of trees. Most of the significant trees stand along the south and western areas, and are mostly within the wetland and wetland buffer, or a steep slope at the southwest corner of the site. Red alder, Bigleaf maple, Western red-cedar, and Scouler’s willow make up the majority of the trees onsite in size and quantity (Exhibits 4, 8, 9 & 14). Other tree species on the site include Douglas-fir, Western hemlock, City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 10 of 13 ERC Report 15-000242 Moss cypress, Spanish fir, Pine, Black cottonwood, English holly, and Norway spruce. There are approximately 114 trees over 6 inches in diameter on the parcel proposed to be developed. After street and critical area deductions, and the minimum requirement to retain 20%, the applicant is proposing to retain none of the required 6.2 trees (Exhibit 8). Attached dwellings are required to maintain a minimum tree density of (4) significant trees for every five thousand (5,000) square feet on each residential lot. The tree density may consist of existing trees or replacement trees. Rather than retain the required 6 trees, the applicant is proposing to replant the site with 126 new trees (not including street trees). The proposed tree species includes Katsura, Elm, Flowering dogwood, Japanese snowbell, Paperbark maple, vine maple, serviceberry, cornelian cherry, flowering dogwood, Leyland cypress, black pine, incense cedar, and western arborvitae at 2-inches in caliper, 6’ to 10’ in height (Exhibit 14). These proposed replacement trees exceed the minimum required replacement inches, 12 inches (12”) for every tree that was unable to be retained, or 37 inches (37”) for the project (6.2” x 12” = 74.4 required replacement inches; 74.4”/2” per tree = 37.2 trees required for replacement). A final detailed landscape plan must be submitted and approved prior to issuance of the street and utility construction permits (Exhibit 9). Mitigation Measure(s): No further mitigation required. Nexus: Not applicable 4. Historic and Cultural Preservation Impacts: Historically the Cedar River has meandered downstream in the Renton-Maple Valley area across the width of the river valley. Furthermore, developments within the vicinity of the Cedar River are more likely to be sites where significant historic and/or cultural resources would be found, and the subject development has indicated that site grading would be conducted. In addition, the Washington State Historic Preservation Officer (SHPO) and Department of Archaeology and Historic Preservation (DAHP) considers this site to have a high probability for containing precontact and historical archaeological resources because it is adjacent to the historical channel of the Cedar River and a portion of a historic trail system is within the project area (Exhibit 26). Therefore, staff recommends a mitigation measure that would require a professional archaeological survey of the project area shall be conducted prior to ground disturbance and also require the applicant and/or developer to stop work and immediately notify the City of Renton planning department, concerned Tribes’ cultural committees, and the Washington State Department of Archeological and Historic Preservation if any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found. Mitigation Measures: 1. A professional archaeological survey of the project area shall be conducted prior to ground disturbance. The results of the professional archaeological survey shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. 2. If any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found, all construction activity shall stop and the owner/developer shall immediately notify the City of Renton planning department, concerned Tribes’ cultural committees, and the Washington State Department of Archeological and Historic Preservation. City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 11 of 13 ERC Report 15-000242 Nexus: SEPA Environmental Regulations, RCW 27.44 Indian graves and records and RCW 27.53.060 Disturbing archaeological resource or site—Permit required—Conditions—Exceptions—Penalty. 5. Transportation Impacts: All new residential subdivisions are required by Renton Municipal Code to establish access to a public road for each segregated parcel (RMC 4-7-080B.2); therefore, a direct public connection to SR 169 is being pursued. Vehicular access to the vacant site is proposed via a new channelized plan that would provide vehicular and residential access connection to SR-169 (under review by WSDOT for compliance state transportation policies and guidelines), which would be located approximately 875 feet east of the Molasses Creek development access, approximately 133 feet west of the single family driveway access to 14235 Maple Valley Hwy, and approximately 552 feet west of Pioneer Place at 145th Ave SE. WSDOT approval of the channelization plan would be subject to a right-in/right-out configuration only from Road A to SR 169 (Exhibits 22-23). Preliminary review of the channelization plan by WSDOT would require a covenant to be placed on the face of the plat to vacate the plats direct public access to SR 169 when a future access to a public road can be achieved either through Molasses Creek Condominium (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. Therefore, staff recommends a mitigation measure that the applicant record a covenant on the face of the plat to vacate the plats direct public access to SR 169 when a future access to a public road can be achieved either through Molasses Creek Condominium (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. For example, “The City of Renton, at the request of the Washington State Department of Transportation, may modify, vacate, and/or eliminate the direct access connection to State Route 169, in the event that direct access from the plat to State Route 169 is provided via a public right-of-way over and across the Molasses Creek Condominiums property located to the west of the plat (APN 556890-0000).” The proposed project also includes abandoning the former single family driveway connection approximately 515 feet east of the Molasses Creek development access (Exhibit 24). Secondary access to the site is proposed via an existing easement that goes through the adjacent MCC project. The easement originates from SR 169 and 140th Way SE and connects through MCC to Elliott Farms west property line (Exhibit 19). The homeowners association of the new project would enter into an agreement with the Molasses Creek Homeowner’s Association for their proportionate share of maintenance of the off-site private road network. The applicant has proposed a street modification that includes several different cross sections to accommodate vehicles, pedestrians, street trees, and street lights. The proposed roadway would provide a paved width of 20 feet with sidewalks that are separated from the vehicle lanes for most of the length of the roadway. Residential street lighting would be provided onsite. Three (3) tracts for alley access is proposed for 16 lots. Road improvements would be completed on SR 169, including curb, gutter, sidewalk, and a planter strip, subject to design review and approval by WSDOT (Exhibit 5). This may include dedication of right-of-way for future planned widening of SR- 169 to accommodate 6, 12-foot lanes and 8-foot shoulders. A Traffic Impact Analysis prepared by TENW (dated April 1, 2015, revised date December 1, 2015; Exhibit 12) was submitted with the application materials. The proposed 45-lot subdivision would generate 321 new weekday daily trips, with 27 new trips occurring during the weekday AM peak hour (5 entering, 22 exiting), and 31 new trips occurring during the weekday PM peak hour (21 entering, 10 exiting). Based on the LOS results conducted at three study intersections, all City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 12 of 13 ERC Report 15-000242 intersections are expected to operate at acceptable levels (LOS D or better) during the AM and PM peak hours in 2017 with no significant impacts created by the proposed Elliott Farm. An annual growth rate of two percent was applied to the existing volumes. The traffic report concludes by stating that traffic impact fees would mitigate long-term traffic impacts, as created by Elliott Farms residential project. The 2016 impact fee for condominium/townhome is $1,546.31 per dwelling unit. Based on 45 new dwelling units, the resulting impact fee would be $69,583.95 (45 X 1,546.31 per unit). Payment of transportation impact fees is applicable at the time of issuance of the building permit. The City of Renton transportation impact fee rate schedule is subject to change. It is not anticipated that the proposed project significantly adversely impacts the City of Renton’s street system subject to the payment of code-required impact fees and the construction of code- required frontage improvements (Exhibit 27). The fee, as determined by the Renton Municipal Code at the time of building permit issuance, shall be payable to the City. A concurrency recommendation would be provided in the staff report to Hearing Examiner based upon the test of the citywide Transportation Plan, consideration of growth levels included in the LOS‐tested Transportation Plan, payment of a Transportation Mitigation Fee, and an application of site specific mitigation. The development would have to meet the City of Renton concurrency requirements. Mitigation Measure(s): The applicant shall record a covenant on the face of the plat to vacate the plats direct public access to SR 169 when a future access to a public road can be achieved either through Molasses Creek Condominium (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. Nexus: RMC 4-6-060F.9 Vehicular Access and Connection Points To and From the State Highway System and Chapter 47.50 RCW, Highway Access Management. 6. Fire & Police Impacts: Police and Fire Prevention staff indicated that sufficient resources exist to furnish services to the proposed development subject to the construction of code-required improvements and the payment of code-required impact fees (Exhibit 27). Mitigation Measure(s): No further mitigation required. Nexus: Not applicable E. Comments of Reviewing Departments The proposal has been circulated to City Department and Division Reviewers. Where applicable, their comments have been incorporated into the text of this report and/or listed under Exhibit 27 “Advisory Notes to Applicant.”  Copies of all Review Comments are contained in the Official File and may be attached to this report. The Environmental Determination decision will become final if the decision is not appealed within the 14-day appeal period (RCW 43.21.C.075(3); WAC 197-11-680). City of Renton Department of Community & Economic Development Environmental Review Committee Report ELLIOTT FARMS PRELIMINARY PLAT LUA15-000242, ECF, PP, SA-H, MOD Report of August 31, 2015; September 14, 2015; July 11, 2016 Page 13 of 13 ERC Report 15-000242 Environmental Determination Appeal Process: Appeals of the environmental determination must be filed in writing together with the required fee to: Hearing Examiner, City of Renton, 1055 South Grady Way, Renton, WA 98057, on or before 5:00 p.m. on July 29, 2016. RMC 4-8-110 governs appeals to the Hearing Examiner and additional information regarding the appeal process may be obtained from the City Clerk’s Office, Renton City Hall – 7th Floor, (425) 430-6510. SEPA ADVISORY NOTES TO APPLICANT LUA15-000242 April 13, 2015 Name: Elliott Farms Application Date:14207 Maple Valley Hwy Renton, WA 98058-8120 Site Address: PLAN - Planning Review - Land Use Version 1 | July 29, 2015 Police Plan Review Comments Contact: Cyndie Parks | 425-430-7521 | cparks@rentonwa.gov Recommendations: Minimal impact on Police Services Fire Review - Building Comments Contact: Corey Thomas | 425-430-7024 | cthomas@rentonwa.gov Recommendations: Environmental Impact Comments: 1.Fire impact fees are applicable at the rate of $495.10 per unit. This fee is paid at time of building permit issuance. Code Related Comments: 1.Comments based on no fire sprinkler systems, no fire alarm systems and construction per the International Residential Code. 2.The preliminary required fire flow for this proposed development is 2,500 gpm. A minimum of three fire hydrants are required. One within 150 feet and two within 300 feet of the proposed buildings. Existing hydrants can be counted toward the requirement as long as they meet current code, including 5 inch storz fittings. A water availability certificate is required from Cedar River Water and Sewer District. 3.Fire department apparatus access roadways are required to be minimum 20 feet wide fully paved, with 25 feet inside and 45 feet outside turning radius. Fire access roadways shall be constructed to support a 30 ton vehicle with 75 psi point loading. Access is required within 150 feet of all points on the buildings. All roads shall be a minimum 20 feet wide including road to lots 24 through 26. Not 17 feet as proposed. Technical Services Comments Contact: Bob MacOnie | 425-430-7369 | bmaconie@rentonwa.gov Recommendations: CC&Rs: Bob Mac Onie 05/15/2015 Elliott Farms is identified as a Short Plat in the Recitals this is incorrect. Recommendations: Preliminary Plat: Bob Mac Onie 5/15/2015 Note the City of Renton land use action number and land record number, LUA15 000242 and LND 10 0523, respectively, on the final short plat submittal. The type size used for the land record number should be smaller than that used for the land use action number. Please note that the land use action number provided will change when this subdivision changes from preliminary to final plat status. Show two ties to the City of Renton Survey Control Network. The geometry will be checked by the city when the ties have been provided. Provide sufficient information to determine how the plat boundary was established. Include a statement of equipment and procedures used, per WAC32 130 100. Note the date the existing city monuments were visited and what was found, per WAC 332 130 150. Provide lot closure calculations. Indicate what has been, or is to be, set at the corners of the proposed lots. Note discrepancies between bearings and distances of record and those measured or calculated, if any. The lot addresses will be provided by the city at final plat submittal. Note said addresses and the street name on the plat drawing. On the final plat submittal, remove all references pertaining to utilities facilities, trees, concrete, gravel, decks and other items not directly impacting the subdivision. These items are provided only for preliminary plat approval. Do note encroachments. Remove from the “LEGEND” block all tree items, utilities facilities and mailbox references, but do include in said “LEGEND” block the symbols and their details that are used in the plat drawing. Do not include a utility provider’s block, an owner’s block, an engineer/surveyor block and an architect block. Page 1 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 1 | July 29, 2015 Technical Services Comments Contact: Bob MacOnie | 425-430-7369 | bmaconie@rentonwa.gov Do not include any references to use, density or zoning on the final submittal If the abutting properties are platted, note the lot numbers and plat name on the drawing otherwise note them as ‘Unplatted’. Do not show building setback lines from the proposed lots. Setbacks will be determined at the time that building permits are issued. Note the research resources on the plat submittal. Note all easements, covenants and agreements of record on the plat drawing. The City of Renton “APPROVALS” blocks for the City of Renton Administrator, Public Works Department, the Mayor, City Clerk and the Finance Director . A pertinent approval block is also needed for the King County Assessor’s Office. Provide signature lines as required. Do not make references to density and zoning information on the final plat drawing. If there is a Restrictive Covenants, Conditions & Restrictions document for this plat, then reference the same on the plat drawing and provide a space for the recording number thereof. Note that if there are restrictive covenants, agreements or easements to others (neighboring property owners, etc.) as part of this subdivision, they can be recorded concurrently with the plat. The plat drawings and the associated document(s) are to be given to the Project Manager as a package. The plat document will be recorded first (with King County). The recording number(s) for the associated document(s) (said documents recorded concurrently with, but following the plat) need to be referenced on the plat drawings. Include the following blocks: TRACT NOTES A ‘Tract’ is land reserved for specified uses, including, but not limited to reserve tracts, recreation, open space, critical areas, surface water retention, utility facilities and access. Tracts are not considered building sites for the purposes of residential dwelling. Tract ‘998‘ is a Storm Drainage tract; upon the recording of this plat, Tract ‘A’ is hereby granted and conveyed to the Elliot Farms Home Owners Association (HOA). An easement is hereby granted and conveyed to the City of Renton over, under and across Tract ‘998’ is a wetland management and critical area tract and is subject to a Native Growth Protection Easement. In the event that the HOA is dissolved or otherwise fails to meet its property tax obligations, as evidenced by non payment of property taxes for a period of eighteen (18) months, then each lot in this plat shall assume and have an equal and undivided ownership interest in Tract ‘998’ previously owned by the HOA and have the attendant financial and maintenance responsibilities. Tract ‘999’ is an Access, Landscape, Recreation, Open Space and Pedestrian Access tract; upon the recording of this plat, Tract ‘999’ is hereby granted and conveyed to the Elliot Farms Home Owners Association (HOA). Maintenance of all improvements and landscaping on said Tract ‘999’ shall be the responsibility of the HOA. In the event that the HOA is dissolved or otherwise fails to meet its property tax obligations, as evidenced by non payment of property taxes for a period of eighteen (18) months, then each lot in this plat shall assume and have an equal and undivided ownership interest in the Tract ‘999’ previously owned by the HOA and have the attendant financial and maintenance responsibilities. Development, alteration, or disturbance within the tract is prohibited except for purposes of habitat enhancement as part of an enhancement project which has received prior written approval from the City and except for required maintenance of the utilities located within the tracts that is granted written City of Renton authorization and conducted using best available science. Note: Tract 999 should be segregated into at least two separate tracts, one for access and the other of Landscaping, Recreation and Open Space. NATIVE GROWTH PROTECTION EASEMENT The Native Growth Protection Easement (NPGE) on this Plat identifies critical areas steep slopes & wetlands. The creation of the Easement conveys to the public a beneficial interest in the land within the Easement Area. This interest shall be for the purpose of preserving native vegetation for the control of surface water and erosion, maintenance of slope stability, visual and aural buffering, and protection of plant and animal habitat. The Easement imposes upon all present and future owners and occupiers of the Easement area enforceable on behalf of the public by the City of Renton, to leave undisturbed all trees and other vegetation within the Easement area. Page 2 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 1 | July 29, 2015 Technical Services Comments Contact: Bob MacOnie | 425-430-7369 | bmaconie@rentonwa.gov The vegetation within the Easement area may not be cut, pruned covered by fill, removed or damaged without express written permission from the City of Renton. All vested owner(s) of the subject plat, at the time of recording, need to sign the final plat. For the street dedication process, include a current title report noting the vested property owner. Community Services Review Comments Contact: Leslie Betlach | 425-430-6619 | LBetlach@rentonwa.gov Recommendations: A. ENVIRONMENTAL IMPACT COMMENTS (from Community Services) 1. Parks Impact Fee per Ordinance 5670 applies. 2. Street Trees: Space street trees 40 feet on center, not 30 feet on center. 30 Feet to street lights or further. Playground exists at new entrance. Page 3 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 2 | December 16, 2015 Community Services Review Comments Contact: Leslie Betlach | 425-430-6619 | LBetlach@rentonwa.gov Recommendations: 1. Parks Impact fee per Ordinace 5670 applies. Recommendations: 2. Trees shall be spaced 40 feet on center, 30 feet from street lights, 6 feet from fire hydrants, waterlines, and sewerlines, 10 feet from driveway approaches, 40 feet from traffic signs (stop, yield, etc.) and intersections without signs. Use only small maturing street trees if overhead electric wires exist. Other landscape trees shall also be small maturing species where overhead utilities exist. Engineering Review Comments Contact: Kamran Yazdidoost | 425-430-7382 | kyazdidoost@rentonwa.gov Recommendations: 8 13 2015 EXISTING CONDITIONS: WATER: Water service will be provided by the Cedar River Water and Sewer District. SEWER: Sewer service will be provided by the Cedar River Water and Sewer District. STORM: There is conveyance/structure system at NE corner of the subject property.. STREETS: There are no frontage improvements. CODE REQUIREMENTS Water Water service will be provided by Cedar River Water and Sewer District. A Water availability certificate will be required. Sewer 1. Sewer service will be provided by Cedar River Water and Sewer District. A Sewer availability certificate will be required. Surface Water 1.There is conveyance/structure system at NE corner of the subject property. 2. A drainage plan and drainage report dated April 10, 2015 was submitted by Barghausen Consulting Engineers. The proposed 45 lot subdivision, zoned R 14, is subject to Full Drainage Review in accordance with the 2009 King County Surface Water Manual and City of Renton Amendments to the KCSWM, Chapters 1 and 2. The 6.07 acre site is located within the Lower Cedar River basin. Based on the City’s flow control map, this site falls within the Flow Control Duration Standard, Forested Site Condition. Surface water runoff created by this development will be collected through a series of new catch basins and pipe systems in the new roadways in two drainage basins. One basin will be drained to the existing conveyance system in Molasses Creek and the other one will drain to a proposed 24 inch conveyance system along the project fronting WA 169. Flow control is not required for this project as the project is within half mile with Cedar River and can direct discharge to Cedar River per City of Renton Amendment to King County Storm water design manual section 1.2.3.1, provided that the direct discharge exemption requirements, as described in the City Amendments to the 2009 KCSWDM, are met. The drainage report must include the level 3 conveyance capacity analysis of the downstream system to the outlet for the total tributary area to the outfall as required by the 2009 KCSWDM amended by City Of Renton to demonstrate that there is sufficient capacity in the existing and proposed storm system and that the approval of direct discharge will not cause flooding. Water quality is required for this Development and developer is intending to use existing off site wet pond for water quality. The off site wet pond was built by previous development. Water quality treatment for the Elliot Farm’s development must be provided per the 2009 King County Storm Water Design Manual. Applicant must provide a copy of the drainage report that was initially developed for the cottonwood, molasses creek and the proposed Elliot farm’s developments that sized and approved the water quality pond by King County. 3.A geotechnical report, dated February 25, 2015 was submitted by Terra Associates, Inc. The field study included eight exploration pits on the 6.07 acre site. These exploration pits were dug up to 15 feet in native’s soil. Ground water/seepage was observed in 5 of the eight test pits. The seepage occurred below depths of about five feet. Soil types encountered are glacially derived and alluvial. The glacial and alluvial soils have low permeability and would not be a suitable receptor soil for discharge of development stormwater using infiltration/retention facilities. 4.Surface water system development fee is $0.540 per square foot of new impervious surface, but not less than $1012. This is payable prior to issuance of the construction permit. 5.A Construction Stormwater Permit from Department of Ecology is required if clearing and grading of the site exceeds one acre. A Stormwater Pollution Prevention Plan (SWPPP) is required for this site. Transportation/Street Page 4 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 2 | December 16, 2015 Engineering Review Comments Contact: Kamran Yazdidoost | 425-430-7382 | kyazdidoost@rentonwa.gov 1.Frontage improvements along SR 169 will be required and are subject to design review and approval by WSDOT. This may include dedication of right of way for future planned widening of SR 169 to accommodate 6, 12 foot lanes and 8 foot shoulders. If curbs are used, shoulder may be reduced to 4 feet. 2.To meet the City’s complete street standards, the new internal roadway shall be designed to meet the residential access roadway per City code 4 6 060. The new internal roadway shall be a 53 foot right of way, with 26 feet of pavement, curb, gutter, an 8 foot planter strip, a 5 foot sidewalk and LED street lighting installed along both sides of the street. One side of the road must be marked NO PARKING. 3.Sidewalk should be continued south side of the roadway front of lot 24 to lot 27, lot 34 to lot 45, and common area to match existing sidewalk to Molasses creek sidewalk. 4.A traffic analysis dated December April 1, 2015 was provided by TENW. The traffic study is required to include all impacted intersections: SE Renton Maple Valley RD/ 140TH Way SE, SE Renton Maple Valley RD/ Molasses Creek East Access, and Molasses Creek West Access/ 140TH Way SE. The proposed 45 lot subdivision would generate approximately 321 new weekday daily trips, with 27 new trips occurring during the weekday AM peak hour (5 entering, 22 exiting) , and 31 new trips occurring during weekday PM peak hour (21 entering, 10 exiting). 5.Primary streets/intersection impacted by this development are: a)SE Renton Maple Valley RD/ 140TH Way SE b)SE Renton Maple Valley RD/ Molasses Creek East Access c)Molasses Creek West Access/ 140TH Way SE 6.Increased traffic created by the development will be mitigated by payment of transportation impact fees of approximately $53,137.80. 7. Mailbox locations shall be approved by the Post Office. 8.LED street lighting meeting the residential lighting standards will be required per City of Renton Standards. 9.Paving and trench restoration will comply with the City’s Trench Restoration and Overlay Requirements. 10.The maximum width of single loaded garage driveway shall not exceed nine feet (9') and double loaded garage driveway shall not exceed sixteen feet (16'). 11.The subject property is within the well field Capture Zone/Aquifer area Zone II. The project must comply with special requirement # 6 (Aquifer Protection Area) per City of Renton Amendment to King County Storm water design manual. General Comments 1. All construction utility permits for drainage and street improvements will require separate plan submittals. All utility plans shall conform to the Renton Drafting Standards. A licensed Civil Engineer shall prepare the civil plans. 2. Rockeries or retaining walls greater than 4 feet in height will be require a separate building permit. Structural calculations and plans shall be submitted for review by a licensed engineer. Special Inspection is required. 3. A tree removal and tree retention/protection plan and a separate landscape plan shall be included with the civil plan submittal. 4. A separate street lighting plan shall be included with the civil drawings. 5.All utilities serving the site are required to be undergrounded. Fire Review - Building Comments Contact: Corey Thomas | 425-430-7024 | cthomas@rentonwa.gov Recommendations: Environmental Impact Comments: 1.Fire impact fees are applicable at the rate of $495.10 per unit. This fee is paid at time of building permit issuance. Code Related Comments: 1.Comments based on no fire sprinkler systems, no fire alarm systems and construction per the International Residential Code. Page 5 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 2 | December 16, 2015 Fire Review - Building Comments Contact: Corey Thomas | 425-430-7024 | cthomas@rentonwa.gov 2.The preliminary required fire flow for this proposed development is 2,500 gpm. A minimum of three fire hydrants are required. One within 150 feet and two within 300 feet of the proposed buildings. Existing hydrants can be counted toward the requirement as long as they meet current code, including 5 inch storz fittings. A water availability certificate is required from Cedar River Water and Sewer District. 3.Fire department apparatus access roadways are required to be minimum 20 feet wide fully paved, with 25 feet inside and 45 feet outside turning radius. Fire access roadways shall be constructed to support a 30 ton vehicle with 75 psi point loading. Access is required within 150 feet of all points on the buildings. All roads shall be a minimum 20 feet wide including road to lots 24 through 26. Not 17 feet as proposed. Planning Review Comments Contact: Clark Close | 425-430-7289 | cclose@rentonwa.gov If applicable, a subdivision with fee simple lots requires that the internal roadway to be made public. Therefore, the roadway design must comply with the residential access road standards of the Renton Municipal Code (RMC 4 6 060 Street Standards). If applicable, update the Traffic Assessment prepared by Transportation Engineering Northwest (TENW) to reevaluate the change in access classification at the SR 169 / Road A intersection. Redesign the project into condominiums in order to retain private roads throughout the project OR provide a public access roadway to each segregated fee simple lots as part of the plat redesign, such that a direct connection from the internal public roadway is made to SR 169/Maple Valley Highway. Police Plan Review Comments Contact: Holly Trader | 425-430-7519 | htrader@rentonwa.gov Recommendations: Minimal impact on police services. Technical Services Comments Contact: Amanda Askren | 425-430-7369 | aaskren@rentonwa.gov Recommendations: CC&Rs: Comments previously from Bob Mac Onie on 05/15/2015 Elliott Farms is identified as a Short Plat in the Recitals this is incorrect. Comments are the same previously from Bob Mac Onie on 05/15/2015 Note the City of Renton land use action number and land record number, LUA15 000242 and LND 10 0523, respectively, on the final short plat submittal. The type size used for the land record number should be smaller than that used for the land use action number. Please note that the land use action number provided will change when this subdivision changes from preliminary to final plat status. Show two ties to the City of Renton Survey Control Network. The geometry will be checked by the city when the ties have been provided. Provide sufficient information to determine how the plat boundary was established. Include a statement of equipment and procedures used, per WAC332 130 100. Note the date the existing city monuments were visited and what was found, per WAC 332 130 150. Provide lot closure calculations. Indicate what has been, or is to be, set at the corners of the proposed lots. Note discrepancies between bearings and distances of record and those measured or calculated, if any. The lot addresses will be provided by the city at final plat submittal. Note said addresses and the street name on the plat drawing. On the final plat submittal, remove all references pertaining to utilities facilities, trees, concrete, gravel, decks and other items not directly impacting the subdivision. These items are provided only for preliminary plat approval. Do note encroachments. Remove from the “LEGEND” block all tree items, utilities facilities and mailbox references, but do include in said “LEGEND” block the Page 6 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 2 | December 16, 2015 Technical Services Comments Contact: Amanda Askren | 425-430-7369 | aaskren@rentonwa.gov symbols and their details that are used in the plat drawing. Do not include a utility provider’s block, an owner’s block, an engineer/surveyor block and an architect block. Do not include any references to use, density or zoning on the final submittal If the abutting properties are platted, note the lot numbers and plat name on the drawing otherwise note them as ‘Unplatted’. Do not show building setback lines from the proposed lots. Setbacks will be determined at the time that building permits are issued. Note the research resources on the plat submittal. Note all easements, covenants and agreements of record on the plat drawing. The City of Renton “APPROVALS” blocks for the City of Renton Administrator, Public Works Department, the Mayor, City Clerk and the Finance Director . A pertinent approval block is also needed for the King County Assessor’s Office. Provide signature lines as required. Do not make references to density and zoning information on the final plat drawing. If there is a Restrictive Covenants, Conditions & Restrictions document for this plat, then reference the same on the plat drawing and provide a space for the recording number thereof. Note that if there are restrictive covenants, agreements or easements to others (neighboring property owners, etc.) as part of this subdivision, they can be recorded concurrently with the plat. The plat drawings and the associated document(s) are to be given to the Project Manager as a package. The plat document will be recorded first (with King County). The recording number(s) for the associated document(s) (said documents recorded concurrently with, but following the plat) need to be referenced on the plat drawings. Include the following blocks: TRACT NOTES A ‘Tract’ is land reserved for specified uses, including, but not limited to reserve tracts, recreation, open space, critical areas, surface water retention, utility facilities and access. Tracts are not considered building sites for the purposes of residential dwelling. Tract ‘998‘ is a Storm Drainage tract; upon the recording of this plat, Tract ‘A’ is hereby granted and conveyed to the Elliot Farms Home Owners Association (HOA). An easement is hereby granted and conveyed to the City of Renton over, under and across Tract ‘998’ is a wetland management and critical area tract and is subject to a Native Growth Protection Easement. In the event that the HOA is dissolved or otherwise fails to meet its property tax obligations, as evidenced by non payment of property taxes for a period of eighteen (18) months, then each lot in this plat shall assume and have an equal and undivided ownership interest in Tract ‘998’ previously owned by the HOA and have the attendant financial and maintenance responsibilities. Tract ‘999’ is an Access, Landscape, Recreation, Open Space and Pedestrian Access tract; upon the recording of this plat, Tract ‘999’ is hereby granted and conveyed to the Elliot Farms Home Owners Association (HOA). Maintenance of all improvements and landscaping on said Tract ‘999’ shall be the responsibility of the HOA. In the event that the HOA is dissolved or otherwise fails to meet its property tax obligations, as evidenced by non payment of property taxes for a period of eighteen (18) months, then each lot in this plat shall assume and have an equal and undivided ownership interest in the Tract ‘999’ previously owned by the HOA and have the attendant financial and maintenance responsibilities. Development, alteration, or disturbance within the tract is prohibited except for purposes of habitat enhancement as part of an enhancement project which has received prior written approval from the City and except for required maintenance of the utilities located within the tracts that is granted written City of Renton authorization and conducted using best available science. Tract 999 should be segregated into at least two separate tracts, one for access and the other of Landscaping, Recreation and Open Space. NATIVE GROWTH PROTECTION EASEMENT The Native Growth Protection Easement (NPGE) on this Plat identifies critical areas steep slopes & wetlands. The creation of the Page 7 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 2 | December 16, 2015 Technical Services Comments Contact: Amanda Askren | 425-430-7369 | aaskren@rentonwa.gov Easement conveys to the public a beneficial interest in the land within the Easement Area. This interest shall be for the purpose of preserving native vegetation for the control of surface water and erosion, maintenance of slope stability, visual and aural buffering, and protection of plant and animal habitat. The Easement imposes upon all present and future owners and occupiers of the Easement area enforceable on behalf of the public by the City of Renton, to leave undisturbed all trees and other vegetation within the Easement area. The vegetation within the Easement area may not be cut, pruned covered by fill, removed or damaged without express written permission from the City of Renton. All vested owner(s) of the subject plat, at the time of recording, need to sign the final plat. For the street dedication process, include a current title report noting the vested property owner. Page 8 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 3 | April 22, 2016 Planning Review Comments Contact: Clark Close | 425-430-7289 | cclose@rentonwa.gov A covenant would be required to be placed on the face of the plat to vacate the parcels direct public access to SR 169 when a future access to a public road can be achieved either through the existing Molasses Creek Condominiums (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. Public access from Elliott Farms subdivision to SR 169 would be required to provide channelization (right in/right out only) from Road B to SR 169. A subdivision with fee simple lots requires that the internal roadway to be made public. Therefore, the roadway design must comply with the residential access road standards of the Renton Municipal Code (RMC 4 6 060 Street Standards). Submit an approved right in/right out (RIRO) channelization plan from WSDOT. Engineering Review Comments Contact: Ann Fowler | 425-430-7382 | afowler@rentonwa.gov 1. 1 ft maintenance strip is to be located behind ROW (typ) 2. Taper landscaping across frontage of lot 18. Align lot 17 with roadway. Shift backyard boundaries as applicable for these lots. 3. Terminate sidewalk at lot 18 and join to pedestrian path through development. 4. Provide mailbox location and vehicular access/parking to mailbox. Fire Review - Building Comments Contact: Corey Thomas | 425-430-7024 | cthomas@rentonwa.gov Recommendations: Environmental Impact Comments: 1.Fire impact fees are applicable at the rate of $495.10 per unit. This fee is paid at time of building permit issuance. Code Related Comments: 1.Comments based on no fire sprinkler systems, no fire alarm systems and construction per the International Residential Code. 2.The preliminary required fire flow for this proposed development is 2,500 gpm. A minimum of three fire hydrants are required. One within 150 feet and two within 300 feet of the proposed buildings. Existing hydrants can be counted toward the requirement as long as they meet current code, including 5 inch storz fittings. A water availability certificate is required from Cedar River Water and Sewer District. 3.Fire department apparatus access roadways are required to be minimum 20 feet wide fully paved, with 25 feet inside and 45 feet outside turning radius. Fire access roadways shall be constructed to support a 30 ton vehicle with 75 psi point loading. Access is required within 150 feet of all points on the buildings. All roads shall be a minimum 20 feet wide including road to lots 5 through 13. Not 16 feet as proposed. Page 9 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 4 | July 14, 2016 Planning Review Comments Contact: Clark Close | 425-430-7289 | cclose@rentonwa.gov RESOLVED: A covenant would be required to be placed on the face of the plat to vacate the parcels direct public access to SR 169 when a future access to a public road can be achieved either through the existing Molasses Creek Condominiums (parcel no. 5568900000) road network or via a redevelopment of the Molasses Creek parcel. Public access from Elliott Farms subdivision to SR 169 would be required to provide channelization (right in/right out only) from Road B to SR 169. Recommendations: 1. RMC section 4 4 030.C.2 limits haul hours between 8:30 am to 3:30 pm, Monday through Friday unless otherwise approved by the Development Services Division. 2. Multi family and other nonresidential construction activities shall be restricted to the hours between seven o’clock (7:00) a.m. and eight o’clock (8:00) p.m., Monday through Friday. Work on Saturdays shall be restricted to the hours between nine o’clock (9:00) a.m. and eight o’clock (8:00) p.m. No work shall be permitted on Sundays. 3. Within thirty (30) days of completion of grading work, the applicant shall hydroseed or plant an appropriate ground cover over any portion of the site that is graded or cleared of vegetation and where no further construction work will occur within ninety (90) days. Alternative measures such as mulch, sodding, or plastic covering as specified in the current King County Surface Water Management Design Manual as adopted by the City of Renton may be proposed between the dates of November 1st and March 31st of each year. The Development Services Division’s approval of this work is required prior to final inspection and approval of the permit. 4. A National Permit Discharge Elimination System (NPDES) permit is required when more than one acre is being cleared. 5. The applicant will be required to comply with all the code requirements of RMC 4 3 050 Critical Areas. This includes, but is not limited to, placing the critical area within a Native Growth Protection Easement, providing fencing and signage. 6. The applicant may not fill, excavate, stack or store any equipment, dispose of any materials, supplies or fluids, operate any equipment, install impervious surfaces, or compact the earth in any way within the area defined by the drip line of any tree to be retained. 7. The applicant shall erect and maintain six foot (6') high chain link temporary construction fencing around the drip lines of all retained trees, or along the perimeter of a stand of retained trees. Placards shall be placed on fencing every fifty feet (50') indicating the words, “NO TRESPASSING – Protected Trees” or on each side of the fencing if less than fifty feet (50'). Site access to individually protected trees or groups of trees shall be fenced and signed. Individual trees shall be fenced on four (4) sides. In addition, the applicant shall provide supervision whenever equipment or trucks are moving near trees. 8. This permit is shall comply with the Bald and Golden Eagle Protection Act. The permitted is responsible for adhering to the U.S. Fish and Wildlife Service National Bald Eagle Management Guidelines (2007) and /or your U.S. Fish and Wildlife Service permit. RESOLVED: A subdivision with fee simple lots requires that the internal roadway to be made public. Therefore, the roadway design must comply with the residential access road standards of the Renton Municipal Code (RMC 4 6 060 Street Standards). RESOLVED: Submit an approved right in/right out (RIRO) channelization plan from WSDOT. Engineering Review Comments Contact: Ann Fowler | 425-430-7382 | afowler@rentonwa.gov 1. 1 ft maintenance strip is to be located behind ROW (typ) Recommendations: I have reviewed the application for the Elliott Farms at 14207 Maple Valley Hwy (APN(‘s) 2223059004) and have the following comments: EXISTING CONDITIONS Water Water service is provided by the City of Renton. Sewer Wastewater service is provided by the City of Renton. Storm The existing properties do not contain stormwater facilities. There are stormwater mains located in Maple Valley Hwy. CODE REQUIREMENTS WATER 1.The applicant has provided a water availability certificate from Cedar River Water & Sewer District. A copy of the approved water plan from Cedar River Water & Sewer District shall be provided to the City prior to approval of the Utility Construction Permit. SEWER 1.The applicant has provided a sewer availability certificate from Cedar River Water & Sewer District. A copy of the approved water plan from Cedar River Water & Sewer District shall be provided to the City prior to approval of the Utility Construction Permit. SURFACE WATER 1.A surface water development fee of $1,485.00 per new single family dwelling unit will apply. The project proposes the addition of 45 new residences. The estimated total fee is $66,825.00. This is subject to final design and payable prior to issuance of the utility construction permit. Page 10 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 4 | July 14, 2016 Engineering Review Comments Contact: Ann Fowler | 425-430-7382 | afowler@rentonwa.gov 2.A drainage report, dated April 10, 2015, was submitted by Barghausen Consulting Engineers, Inc. with the site plan application. Based on the City of Renton’s flow control map, this site falls within the Flow Control Duration Standard for Forested Conditions. The development is subject to Full Drainage Review in accordance with the 2009 King County Surface Water Design Manual (KCSWDM) and the City of Renton Amendments to the KCSWDM. All core requirements and special requirements have been discussed in the provided drainage report. 3.The existing site is currently undeveloped with remnants from an existing farm, including partially buried building foundations and concrete slabs. The site topography is generally flat with a steep slope in the southwest corner of the site, which also contains a wetland with a 50 foot that will remain undisturbed. A portion of the runoff from the existing site drains to the wetland. The remaining portion of the site drains into a roadside ditch along Maple Valley Hwy (WA 169), where flows are conveyed west. 4.A geotechnical report, dated February 25, 2015, completed by Terra Associates, Inc., for the site has been provided. The field study included eight exploration pits on the 6.07 acre site. These exploration pits were dug up to 15 feet in native soils. Groundwater/seepage was observed in five of the eight test pits. The seepage occurred below depths of about five feet. The report discusses the soil and groundwater characteristics of the site and provides recommendations for project design and construction. Geotechnical recommendations presented in this report discount the use of full infiltration due to the underlying dense glacial till soil. 5.The project site is located within the Lower Cedar River drainage basin and the flowpath from the project site discharge point is less than a half mile to the 100 year floodplain of the Cedar River and qualifies for the direct discharge exemption in accordance with Section 1.2.3.1 of the City Amendments to the KCSWDM and must adhere to all requirements thereof. Staff Comments: i.The conveyance system analysis provided in the preliminary Technical Information Report (TIR) does not provide a complete analysis of the system to the outfall in the Cedar River in accordance with the requirements for the direct discharge exemption as outlined in Section 1.2.3 of the 2009 KCSWDM. Applicant shall provide a complete conveyance system analysis, including new conveyance pipes within the proposed development and existing conveyance pipes from the development boundary to the outfall in the Cedar River. Applicant shall demonstrate the outfall and existing conveyance system is adequately sized to support the added run off from the development. 6.The development is required to provide basic water quality treatment prior to discharge. The development is proposing to convey surface water to an existing water quality facility (wetpond), located at the southwest corner of the WA 169 and 140th Way SE intersection. As stated in the drainage report, the existing off site wetpond was built and sized for several divisions of Cedarwood projects, Molasses Creek Condominiums, areas of the WSDOT right of way, as well as the proposed Elliot Farms project. Staff Comments: i.The applicant shall complete a level 3 downstream analysis verifying capacity of the existing wetpond and conveyance system. ii.The applicant shall provide a copy of the as built plans and final drainage report(s) used to build the Cedarwood Water Quality Pond. 7.No downstream flooding or erosion issues were identified in the drainage report. Additional Staff Comments: i.A Construction Stormwater Permit from Department of Ecology is required. ii.A Stormwater Pollution Prevention Plan is required to be submitted with the construction permit application. TRANSPORTATION 1.The proposed development fronts Maple Valley Hwy (WA 169) along the north property lines. Maple Valley Hwy (WA 169) is classified as a Principal Arterial Road and is a Washington State Highway. Frontage improvements along Maple Valley Hwy (WA 169) will be required and are subject to design review and approval by WSDOT. This may include dedication of right of way for future planned widening of Maple Valley Hwy (WA 169) to accommodate six (6) 12 foot lanes and 8 foot shoulders. If curbs are used, shoulder width may be reduced to 4 feet. Existing right of way (ROW) width is approximately 150 feet. Per City code 4 6 060, half street improvements shall include a pavement width of 88 feet (44 feet from centerline), a 0.5 foot curb, an 8 foot planting strip, an 8 foot sidewalk, street trees and storm drainage improvements. However, the City’s transportation group has determined and will support an alternate standard to match the established standard street section for Maple Valley Hwy (WA 169). The City established standard street section for Maple Valley Hwy (WA 169), which shall be installed by the developer as part of the proposed development, will allow retention of the existing curb line. Developer will be required to install 6 foot planting strips and 5 foot sidewalks behind the existing curb along the frontage of Maple Valley Hwy (WA 169). Staff Comments: i.Applicant will need to submit an application to the City requesting a modification of the street frontage improvements as outlined in City code 4 9 250C5d. ii.The posted speed limit of Maple Valley Hwy (WA 169) is 50 mph along this section of Maple Valley Hwy (WA 169). The City defers to American Association of State Highway and Transportation Officials (AASHTO) standard clear zones, which provide the same, or similar, clear zone requirements as WSDOT. The required clear zone would preclude the developer from being able to install street trees and street lighting along the frontage of Maple Valley Hwy (WA 169) as part of the development. A request for modification or a fee in lieu would Page 11 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 4 | July 14, 2016 Engineering Review Comments Contact: Ann Fowler | 425-430-7382 | afowler@rentonwa.gov be required to not install the street trees and street lighting along Maple Valley Hwy (WA 169) as part of the platting process of Elliott Farms. 2.The proposal includes a new internal roadway providing direct access via Maple Valley Hwy (WA 169) to the north and access through the existing access easement through the existing private lane at Molasses Creek Condominiums (MCC) to the west. The applicant has proposed a street modification to provide a paved roadway width of 20 feet with 5 foot sidewalks and 8 foot planter strips along one side of the roadway. Sidewalks and planter strips alternate between the north side of the roadway and the south side of the roadway in order to provide pedestrian access to the pathways used to connect common areas. Staff Comments: i.Emergency services access within 150 feet of all homes via a 20 foot paved roadway is required. As such, parking is not allowed along the internal access road proposed for the project. 3.The proposal includes three (3) 16 foot wide alleys. Alley 1 provides access to lots 24 26, Alley 2 provides access to lots 5 13, and Alley 3 provides access to lots 1 4. i.Applicant shall submit a modification request for approval by City of Renton Fire Prevention for 16 foot alley access roads to lots 1 13 and 24 26. ii.If the modification request is approved, sprinkler systems would be required for each of the lots accessed from the 16 foot alleys. 4.ADA access ramps shall be installed at all street crossings. Ramps are not shown at the crossing between lots 33 and 34 and at the crossing located at the west end of the development. 5.Street lighting and street trees are required to meet current city standards. Lighting plans were not submitted with the land use application and will be reviewed during the construction utility permit review. 6.A traffic analysis dated April 1, 2015, was provided by Transportation Engineering Northwest (TENW). The site generated traffic volumes were calculated using data from the Institute of Transportation Engineers (ITE) Trip Generation Manual, 9th Edition, (2009). The traffic analysis is required to include all impacted intersections: Maple Valley Hwy (WA 169)/140th Way SE, Maple Valley Hwy (WA 169)/Molasses Creek East Access, and Molasses Creek West Access/140th Way SE. Based on the calculations provided, the proposed development would average 321 new daily vehicle trips. Weekday peak hour AM trips would generate 27 new vehicle trips, with 22 vehicles exiting and 5 vehicles entering the site. Weekday peak hour PM trips would generate 31 new vehicle trips, with 21 vehicles entering and 10 vehicles exiting the site. 7.A supplementary traffic analysis, dated December 11, 2015, was provided by TENW in order to provide an updated analysis of the project assuming a new access to Maple Valley Hwy (WA 169). Traffic volumes remained unchanged from the preliminary analysis previously noted. The estimated distribution of project traffic was based on existing traffic patterns and were generally distributed as follows: •50 percent to/from the west on Maple Valley Hwy (WA 169) •30 percent to/from the east on SE Renton Maple Valley Hwy (WA 169) •20 percent to/from the south on 140th Way SE As detailed in the report the proposed project is not expected to lower the levels of service of the surrounding intersections included in the traffic study. Direct public access to and from the site via Maple Valley Hwy (WA 169) shall be channelized to provide right in/right out access only. Increased traffic created by the development will be mitigated by payment of transportation impact fees. 8.Refer to City code 4 4 080 regarding driveway regulations. Driveways shall be designed in accordance with City standard plans 104.1 and 104.2. 9.Payment of the transportation impact fee is applicable on the construction of the development at the time of application for the building permit. The current rate of transportation impact fee is $1,546.31 per dwelling unit for condominiums. The project proposes the addition of 45 new residences. The estimated total fee is $69,583.95. Traffic impact fees will be owed at the time of building permit issuance. Fees are subject to change. The transportation impact fee that is current at the time of building permit application will be levied. 10.Paving and trench restoration shall comply with the City’s Trench Restoration and Overlay Requirements. GENERAL COMMENTS 1.Adequate separation between utilities shall be provided in accordance with code requirements. a.7 ft minimum horizontal and 1 ft vertical separation between storm and other utilities is required with the exception of water lines which require 10 ft horizontal and 1.5 ft vertical. 2.All construction utility permits for drainage and street improvements will require separate plan submittals. All utility plans shall confirm to the Renton Drafting Standards. A licensed Civil Engineer shall prepare the civil plans. 3.A landscaping plan shall be included with the civil plan submittal. Each plan shall be on separate sheets. 4.All electrical, phone, and cable services and lines serving the proposed development must be underground. The construction of these franchise utilities must be inspected and approved by a City of Renton inspector. 2. Taper landscaping across frontage of lot 18. Align lot 17 with roadway. Shift backyard boundaries as applicable for these lots. 3. Terminate sidewalk at lot 18 and join to pedestrian path through development. Page 12 of 13Ran: July 15, 2016 ADVISORY NOTES TO APPLICANT LUA15-000242 PLAN - Planning Review - Land Use Version 4 | July 14, 2016 Engineering Review Comments Contact: Ann Fowler | 425-430-7382 | afowler@rentonwa.gov 4. Provide mailbox location and vehicular access/parking to mailbox. Community Services Review Comments Contact: Leslie Betlach | 425-430-6619 | LBetlach@rentonwa.gov Recommendations: 1. Parks Impact Fee per Ordinance 5670 applies. 2. Planting strips include an 8 foot wide planting strip at all public street locations. Use large maturing trees where no overhead electric wires exist and spaced 50 feet on center. Fire Review - Building Comments Contact: Corey Thomas | 425-430-7024 | cthomas@rentonwa.gov Recommendations: Environmental Impact Comments: 1.Fire impact fees are applicable at the rate of $495.10 per unit. This fee is paid at time of building permit issuance. Code Related Comments: 1.Comments based on no fire sprinkler systems, no fire alarm systems and construction per the International Residential Code. 2.The preliminary required fire flow for this proposed development is 2,500 gpm. A minimum of three fire hydrants are required. One within 150 feet and two within 300 feet of the proposed buildings. Existing hydrants can be counted toward the requirement as long as they meet current code, including 5 inch storz fittings. A water availability certificate is required from Cedar River Water and Sewer District. 3.Fire department apparatus access roadways are required to be minimum 20 feet wide fully paved, with 25 feet inside and 45 feet outside turning radius. Fire access roadways shall be constructed to support a 30 ton vehicle with 75 psi point loading. Access is required within 150 feet of all points on the buildings. All roads shall be a minimum 20 feet wide including road to lots 5 through 13 and 24 through 26. Not 16 feet as proposed. Turning radius to Alley 2 does not meet code either. Page 13 of 13Ran: July 15, 2016 RESPONSES TO HEARING EXAMINERS DECISION AND SEPA CONDITIONS -1- 21397-COMM Response Matrix.docx RESPONSES TO CONDITIONS OF APPROVAL ELLIOT FARMS PRELIMINARY PLAT FILE NOs. LU15-000242, ECF, PP, SA-H, MOD Our Job No. 21397 CONDITION RESPONSE 1. The applicant shall comply with the mitigation measures issued as part of the Determination of Non-Significance - Mitigated, dated July 15, 2016. Acknowledged. See responses below. 2. The applicant shall install or provide financial guarantees for all common landscaping and open space amenities prior to plat recording. A phasing plan and final detailed landscaping plan shall be submitted with the street and utility construction permits. The financial guarantees will be provided prior to final plat recording. A phasing plan is not applicable. The final landscaping plans are included with the street and utilities plans. 3. The applicant shall incorporate into the landscaping plan a minimum of two (2) active facilities subject to staff approval that provide opportunities for physical exercise and social interaction and low level trail lighting. The details of these amenities shall be identified on the final landscaping plan and shall be submitted to the City of Renton Project Manager with the street and utility construction permits for approval. This condition will be satisfied with the review and approval of the landscape plans. 4. The proposed on-site seven-foot wide trail system shall be paved with concrete, except the trail system located directly behind the rear yards of Lots 34-45. The final detailed trail system and profile plans shall be submitted to the City of Renton Project Manager with the street and utility construction permits. This condition will be satisfied with the review and approval of the final engineering and landscape plans. 5. The applicant shall orient the front doors and front yards of the attached dwelling units on Lots 1-13 toward the street (Road A) or the common open space tracts. Each of these units shall provide a four-foot (4') entry walkway that Final plat and building permit item. -2- 21397-COMM Response Matrix.docx CONDITION RESPONSE connects the front entry to shared common green space trail or sidewalk system. A note to this effect shall be recorded on the face of the Plat map. Each of these units shall be designed to the highest level of architectural detailing and articulation. 6. The applicant shall relocate the shared common green space trail system, which runs north/south between Lots 3-18, to be located closer to the front yards of Lots 5-7 and 8-13 to provide more usable green space behind the lots. The revised plan shall be submitted along with the street and utility construction permits. This condition will be satisfied with the review and approval of the civil plans showing the locations of the trails. 7. The applicant shall submit a revised plat plan that includes a pedestrian entry easement that is at least fifteen feet (15') wide plus a five-foot (5') sidewalk to the north of Lots 24-26. This condition will be satisfied with the review and approval of the civil plans that shows the 5' sidewalk to the north of lots 24-26 in Tract E 8. The plat shall include a minimum of four (4) different building types (models) to provide additional character to the development. The detailed floor and elevation plans shall be submitted to the City of Renton Project Manager with the street and utility construction permits. This condition will be satisfied prior to final engineering approval. 9. Prior to construction permit approval, the applicant shall submit, to the City of Renton Current Project Manager, a site plan and a roofing materials board that identifies a variety of colors throughout the development. The condition will be satisfied prior to construction plan approval. 10. The applicant shall provide for the minimum standard of 24 feet (24') along the street curves. A final detailed site plan shall be submitted to, and approved by, the Current Planning Project Manager and the Plan Reviewer prior to construction permit approval. This condition will be satisfied with the review and approval of the final engineering plans which the lots all contain a minimum of 24' along street curves. -3- 21397-COMM Response Matrix.docx CONDITION RESPONSE 11. The applicant shall submit a lighting plan and final detailed landscape plan to, and approved by, the Current Planning Project Manager and the Plan Reviewer prior to construction permit issuance. This condition will be satisfied with the review and approval of the lighting and landscape plans submitted with the civil permit application. 12. The applicant shall create a Home Owners Association ("HOA") that retains or improves the existing vegetation within the open space tract. A draft HOA document has been submitted as part of the application. A final HOA shall be submitted to, and approved by, the City of Renton Current Project Manager and City Attorney to the extent pertinent to public subdivision review prior to Final Plat recording. Such documents shall be recorded concurrently with the Final Plat. Final plat item. 13. The applicant shall provide public easements for amenities that are outside of the right-of-way of the new public street. This condition will be satisfied with the review and approval of the final engineering plans. 14. The applicant shall provide access signage that identifies the trail system throughout the development for public access. This condition will be satisfied with the review and approval of the final engineering plans. 15. Finding of Fact 4(E) of this decision identifies an outstanding street modification required for a shared driveway standard modification and a variance for fire access width. Unless these requirements are nullified by approved design modifications, approval of the modification and variance is required prior to final plat approval. This condition will be satisfied with the review and approval of the final engineering plans. The alleys have been modified to meet the standards. SEPA -4- 21397-COMM Response Matrix.docx CONDITION RESPONSE B. Mitigation Measures 1. Project construction shall be required to comply with the recommendations found in the Geotechnical Engineering Study prepared by Terra Associates, Inc. dated February 25, 2015 or an updated report submitted at a later date. Notes are provided on the final engineering plans that state this requirement. 2. The applicant shall remove the existing concrete foundations(s) within the wetland buffer and restore the affected areas by planting trees and shrubs within the 50-foot standard wetland buffer by hand without heavy machinery. A tree planting plan shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. This condition will be satisfied with the approval of the civil and landscape plans. The landscape plans contain the planting plans. 3. The applicant shall submit the final drainage report(s) used to build the Cedarwood water quality pond, including the original design, to the City of Renton Plan Reviewer prior to construction issuance. This condition will be satisfied with the review and approval of the final Technical Information Report. 4. A professional archaeological survey of the project area shall be conducted prior to ground disturbance. The results of the professional archaeological survey shall be provided to the Current Planning Project Manager for review and approval prior to construction permit issuance. The archaeological survey is provided in the Technical Information Report. 5. If any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found, all construction activity shall stop and the owner/developer shall immediately notify the City of Renton planning department, concerned Tribes' cultural committees, and the Washington State Department of Archeological and Historic Preservation. This condition will be satisfied with construction. A note is provided on the final engineering plans. 6. The applicant shall record a covenant on the face of the plat to vacate the plats direct public access to SR 169 when a future access to a public road can be achieved either through Molasses Creek Condominium (parcel no. 55689000000) road network or via a redevelopment of the Molasses Creek parcel. Final plat item. Tab 3.0 21397.002-TIR.docx 3.0 OFF-SITE ANALYSIS TASK 1 STUDY AREA DEFINITION AND MAPS The proposed Plat of Elliott Farms is an attached single-family residential project consisting of 45 lots zoned R-14. The tax parcel number is 2223059004 and is 6.07 acres in size. The site is located on the south side and adjacent to Maple Valley Hwy (WA-169) at the eastern terminus of 140th Way SE (Private Road), in a portion of Section 22, Township 23 North, Range 5 East, W.M., in the City of Renton. Please refer to the vicinity map in Section 1.0. The site is rectangular in shape with 691.70’ of frontage along Maple Valley Hwy (WA-169). A condominium site, known as Molasses Creek Phase 1, is located on the west side of the project. A single family residential development, known as Pioneer Place, is located to the east and a single family residence is located south. Ground cover mainly consists of weeds, grass and brush; however, the southwest corner of the site contains a mixed variety of trees. A wetland exists at the southwest corner of the site with a 50’ buffer. This site is currently undeveloped, but contains remnants from an existing farm, including partially buried building foundations and concrete slabs. Existing on-site utilities were constructed along the northern portion of the site for this development. On-site soils are mapped as Newberg (till soils). The on-site topography is generally flat. The southwest corner of the project (approximately 1.85 acres) gently slopes toward the wetland. The wetland is approximately 4-6 feet lower than the edge of the 50’ buffer and drains westerly through more wetlands located behind Molasses Creek before entering into a 24-inch culvert under 140th Ave Se. The remaining portion of the site drains into the roadside ditch along WA-169. There is an existing drainage ditch along the east side of the project that conveys off-site upstream flows from the southeast. The elevations on the site range from 87 to 107. TASK 2 RESOURCE REVIEW  Adopted Basin Plans: The site is located within Mainstem Reach 2 of Lower Cedar River Basin. Refer to Appendix A for the portions of the basin that applies to this project.  Finalized Drainage Studies: This is not applicable.  Basin Reconnaissance Summary Report: This site is located in the Mainstem Reach 2 in Lower Cedar River Basin, which is covered by the Lower Cedar River Basin and Nonpoint Pollution Action Plan dated July 1997 (included in Appendix A).  Critical Drainage Area Maps: This project will not discharge drainage to any critical areas or wetlands as it will be discharging developed run-off to existing conveyance system that is conveyed to an existing water quality facility prior to discharging into the Cedar River. Therefore, no critical areas are to be affected.  Floodplain and Floodway FEMA Maps: Please see the attached FEMA Map (Section 1.0) utilized for this analysis. As indicated on the map, the site is located in Zone X and is outside of the 500-year floodplain.  Other Off-Site Analysis Reports: A site investigation was conducted in preparation of this Level 1 Off-Site Drainage Analysis. The United States Department of Agriculture Soils Conservation Service Map is also provided. See Figure 4 – Soils Map in Section 1.0.  Sensitive Areas Folios: Based on review of the King County Sensitive Areas Map Folios located in this section and special reports prepared by consultants included in Section 6.0 of the TIR, the site contains a wetland and buffer at the southwest corner of the site. The site is also located within an erosion, landslide, and seismic hazard area. 21397.002-TIR.docx  Road Drainage Problems: The project researched drainage complaints from King County and the city of Renton. The city had no records of any downstream drainage complaints within the drainage investigation areas. King County had a listing of the drainage complaints within a mile of the site; however, none of the complaints were within the downstream drainage area and were not applicable.  United States Department of Agriculture King County Soils Survey: Based on the Soils Map (Figure 4 – Soils Map, Section 1.0) for this area, the site contains Newburg (Ng) silt loam with a small portion of Alderwood and Kitsap (AkF), very Steep, located near the south boundary line. The soils were modeled as till soils for drainage computations.  Wetland Inventory Map: From the Wetland Assessment Report by Radakke Associates located in Section 6.0 of this TIR, there is a wetland in the southwest corner of the site.  Migrating River Studies: This is not applicable.  City of Renton Aquifer Protection Zones: Per the City of Renton’s GIS Map, the project site is not located within an Aquifer Recharge Area. TASK 3 FIELD INSPECTION The field inspection for this Level 1 Off-Site Drainage Analysis was conducted on April 3, 2015 for the purpose of analyzing the proposed project site and its upstream and downstream corridors. The weather was cloudy with occasional rain showers. The off-site drainage system was inspected from the project limits to the edge of the outfall at the Cedar River. The boundary and topographic survey and LIDAR map were also used to identify the drainage patterns associated with the property. Upstream Drainage Area The project contains two off-site upstream drainage areas that drain onto the project. See Exhibit A showing the upstream drainage areas. The more southwesterly upstream drainage basin (Basin OS1) area contains 3.3 acres of upstream drainage area. The majority of the area is steep slopes. The upstream drainage area drains to the existing wetland at the southwest corner of the site where flows are then conveyed westerly to a larger wetland. The south easterly upstream drainage area (Basin OS2) contains approximately 17.2 acres. The drainage from this upstream drainage basin is collected in a ditch along the projects easterly boundary line and conveyed to an existing 18-inch culvert crossing WA-169. Onsite Drainage In the pre-developed condition approximately 1.85 acres of the site drains toward the wetland in the southwest corner of the site. The remaining 4.22 acres drains toward the north into the existing ditch along WA-169. 3.1 Conveyance System Nuisance Problems (Type 1) Conveyance system nuisance problems are minor but not chronic flooding or erosion problems that result from the overflow of a constructed conveyance system that is substandard or has become too small as a result of upstream development. Such problems warrant additional attention because of their chronic nature and because they result from the failure of a conveyance system to provide a minimum acceptable level of protection. There were no conveyance system nuisance problems observed during the site visit. Furthermore, based on a review of the drainage complaints received from King County and the City of Renton, there is no evidence of past conveyance system nuisance problems occurring in the direct downstream drainage course, as there are no records that have been submitted. 21397.002-TIR.docx 3.2 Severe Erosion Problems (Type 2) Severe erosion problems can be caused by conveyance system overflows or the concentration of runoff into erosion-sensitive open drainage features. Severe erosion problems warrant additional attention because they pose a significant threat either to health and safety or to public or private property. Based on our site visit, there was no evidence of, or potential for, erosion/incision sufficient to pose a sedimentation hazard downstream within the limits of the study. All runoff sheet flows to existing conveyance channels, where flows are then conveyed off site. Stormwater runoff from the proposed roads and rooftops from the developed project will be collected in catch basins and conveyed through pipes to an existing water quality facility where it will then be discharged directly to the Cedar River. As a result no future erosion problems should occur downstream because of this development. 3.3 Severe Flooding Problems (Type 3) Severe flooding problems can be caused by conveyance system overflows or the elevated water surfaces of ponds, lakes, wetlands, or closed depressions. Severe flooding problems are defined as follows:  Flooding of the finished area of a habitable building for runoff events less than or equal to the 100-year event. Examples include flooding of finished floors of homes and commercial or industrial buildings. Flooding in electrical/heating systems and components in the crawlspace or garage of a home. Such problems are referred to as "severe building flooding problems."  Flooding over all lanes of a roadway or severely impacting a sole access driveway for runoff events less than or equal to the 100-year event. Such problems are referred to as "severe roadway flooding problems." Based on a review of the FEMA Map (Section 1.0) the proposed site is outside of the 500-year floodplain, and there is no evidence of severe flooding problems encountered during our visit. TASK 4 DRAINAGE SYSTEM DESCRIPTION AND PROBLEM DESCRIPTIONS DOWNSTREAM DRAINAGE ANALYSIS: The downstream drainage course does not exhibit any major concerns and appears to contain plenty of capacity to convey the additional developed flows from Elliott Farms. Please refer to Exhibit A for the Upstream/Downstream Drainage Area Map Exhibit B for the Off-site Analysis Drainage System Table. Drainage complaints were requested from the city of Renton and King County Water and Land Resources as required, however, there were no applicable complaints within the downstream drainage course within the last 10 years. In the developed condition, stormwater generated from the new impervious surfaces, including road and rooftops, will discharge in two locations. The westerly portion of the site will discharge into the conveyance system constructed by Molasses Creek and be conveyed to the existing water quality facility (wetpond) before discharging into the Cedar River. The drainage from the north easterly portion of the project will be conveyed to a proposed 24-inch conveyance system that will replace the existing ditch along the WA-169 frontage. From here the drainage will be directed through a series of ditches and culverts before entering into the existing wetpond. 21397.002-TIR.docx TASK 5 MITIGATION OF EXISTING OR POTENTIAL PROBLEMS Mitigation or upsizing of any of the drainage is not required based on the drainage calculations in section 4.0 and 5.0 of this TIR. Please refer to the 100 year Conveyance Capacity Analysis in Section 5.0 showing that the existing conveyance system in Molasses Creek contains enough capacity to convey the future developed flows from Elliott Farms. The project is required to provide frontage improvements along WA-169. This will include installing curb, gutter and sidewalk. The existing ditches will be replaced with a 24-inch piped conveyance system along the frontage and will discharge to the existing ditch. The existing conveyance system appears to contain plenty of capacity to convey the future developed flows from the developed project to the Cedar River. Exhibit A Upstream/Downstream Drainage Area Map 1A1B1C2A2B2C2D2E2F2G2H2J2I2K2L2M3A3B3C2CNumber symbols indicate downstream drainagelocations as identified on the following "OffsiteAnalysis Drainage System Table".18301 Exhibit B Off-Site Analysis Drainage System Table 15734-Off-Site Analysis Drainage System Table.doc OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE Surface Water Design Manual, Core Requirement #2 Basin: Lower Cedar River Subbasin Name: Mainstem Reach 2 Subbasin Number: Location ID Drainage Component Type, Name, and Size Drainage Component Description Slope Distance from Site Discharge Existing Problems Potential Problems Observations of Field Inspector, Resource Reviewer, or Resident See Map Type: sheet flow, swale, stream, channel, pipe, pond; size, diameter, surface area Drainage basin, vegetation, cover, depth, type of sensitive area, volume % Ft. Constrictions, under capacity, ponding, overtopping, flooding, habitat or organism destruction, scouring, bank sloughing, sedimentation, incision, other erosion Tributary area, likelihood of problem, overflow pathways, potential impacts 1A 18” CULVERT Drains across ex gravel road, 17.2 acre up-stream basin 0-1% Discharges onto site Outlet should be maintained Culvert conveying flows to existing ditch 1B Channel 6”- 1’ wide x 1.5 to 2’ deep with gentle side slopes. Covered in blackberry bushes 0-1% Along site’s west boundary line None seen. Flows observed in channel, heavy blackberry bushes 1C 18” CULVERT Crosses under WA-169 0-1% Discharge from Ditch at NE corner of site None seen Flows observed during site visit. Receives flows from pond on Pioneer place and 17.2 acre upstream basin 2A Channel Channel draining east to west along south side of WA-169, 1.5’-2’ deep with 4:1 side slopes 0-1% North boundary of site None noted Grass lined channel with very little slope. 2B 18” culvert Drains under existing access 0-1% 0 None noted No restrictions, outlets to channel 2C Channel Drains West along WA-169, 1.5’ to 2’ deep with 4:1 side slopes 0-1% 0 None noted Grass lined channel with very little slope 2D 18” Culvert Drains under access 0-1% NW corner of site None noted No restrictions, outlets to channel 2E Channel Drains West along WA-169, 1.5-2’ deep with 4:1 side 0-1% 0-220’ None noted Grass lined ditch outletting to 24” D.I. Culvert. Flows 15734-Off-Site Analysis Drainage System Table.doc slopes, receives drainage from WA-169 observed during site visit. 2F 18” D.I. Culvert Drains across paved driveway 0.10% 220-570’ Debris in inlet Culvert should be cleaned and free of debris and sediment 2G Channel Drains West along WA-169 to intersection of 140th Ave, 1.5’ to 2’ deep with 4:1 side slopes 0-1% 570’-1,295 None noted Flows observed in channel. 2H 24” culvert Drains from ditch to CB adjacent to pond 0-1% 1,295 – 1,445 None noted No drainage complaints. Appears to contain enough capacity 2I 24” pipe Inlet to pond 11% 1,445-1463 None noted No drainage complaints. Appears to contain enough capacity 2J Wetpond 1,463- 1,810 None noted No drainage complaints. Appears to contain enough capacity 2K 36” outlet Outlet from wetpond Backsloped No drainage complaints. Appears to contain enough capacity 2L 36” pipe 0.9% 1,810-2,000 None noted No drainage complaints. Appears to contain enough capacity 2M 36” pipe Outfall to Cedar river 0.1% 2,000- 2,200 None noted Outfall was roughly 5’ above water level during site visit 3A 12” pipe conveyance system Receives road and roof top drainage from Molasses Creek development, 2.7’ deep. 1.3% 0-106’ None noted No drainage complaints. Appears to contain enough capacity 3B 30” pipe conveyance system Receives flow from Cedarwood Div. 2 from the south 0.50% 106’- 1,110’ Last catch basin buried and not found No drainage complaints. Appears to contain enough capacity 3C 36” pipe conveyance system Outfall to wepond 0-0.50% 1,110-1,380 Last catch basin full of water and sediment Could not obtain invert elevations due to water and sediment build up. Photo 1 - ditch along east boundary linePhoto 2 - ditch along east boundary line at inletPhoto 3 - ditch outlet at WA-169Photo 4 - ditch along WA-169 frontage Photo 7 - WA-169 18" outlet - Molasses Creek FrontagePhoto 5 - 18" SD at WA-169 crossing Molasses CreekFrontagePhoto 6 - WA-169 18" SD outlet along Molasses CreekFrontage - Looking west.Photo 8 - WA-169 ditch looking east along MolassesCreek Frontage Photo 9 - outlet from WA-169 to wetpondPhoto 10 - wetpondPhoto 11 - Wepond outlet to Cedar RiverPhoto 12 - Outlet to Cedar River Exhibit C Downstream Drainage Complaints King County Water and Land Resources Division - Drainage Services Section Complaint Search Printed : 3/18/2015 10:59:23 AM Number Type Type of Problem Address of Problem Comments Tbros Page 1991-0005 C EROSION 15240 142ND PL SE EROSION FROM PIPE IN RAVINE 656J5 1991-0005 E EROSION 15240 142ND PL SE EROSION FROM PIPE /DRY WELL 656J5 1991-0023 C DRNG 15805 140TH CT SE /POWELL/CONSTRUCTION NO EROSION 656J5 1991-0080 C FLDG 14037 SE 159TH PL WATER AND ICE ON SIDEWALK 656J5 1991-0080 E FLDG 14037 SE 159TH PL RETAINING WALL /PONDING WATER 656J5 1991-0155 C DRNG 14043 SE 159TH PL EXPOSED DRAIN LINE/ROOF 656J5 1991-0155 PN DRNG 14043 SE 159TH PL NOT NDAP 656J5 1991-0345 C DRNG 14031 SE 159TH PL DIVERSION OF WATER TO SIDEWALK 656J5 1992-0414 C DRAINAGE 14059 SE 159TH PL WATER OVER S/W 656J5 1992-0414 E DRAINAGE 14059 SE 159TH PL 656J5 1992-0414 ER DRAINAGE 14059 SE 159TH PL WATER OVER S/W - NOV. MEETING 656J5 1993-0023 C DRAINAGE 14059 SE 159TH ICE ON ROADWAY 656H5 1994-0354 C EASEMENT 13981 SE 159TH PLACE WANTS TO FENCE INSIDE DRAIN ESMT 656H5 1994-0392 C DRNGPIPE 14022 SE 158TH ST WATER OVER SIDEWALK 656J5 1994-0392 E DRNGPIPE 14022 SE 158TH ST WATER OVER SIDEWALK 656J5 1994-0392 ER DRNGPIPE 14022 SE 158TH ST WATER OVER SIDEWALK 656J5 1994-0809 WQC DUMPING SE 159TH PL & 140T SE CONCRETE DISCHARGE/BEAUTY BARK 656J5 1994-0813 C PONDING 14019 SE 158TH ST WATER OVER SIDEWALK MAPLE RIDGE 656J5 1995-0758 WQC DUMPING SE 158TH & 149TH CT NEW D/W CURB CUT & CONC CLEAN- 656J5 1995-1190 CL REIMBURS SR 169-MPLWD GOLF REIMBURSEMENT FOR SAND BAGS - 656H4 1996-0888 FCS OIL 15282 SE MAPLE DR OIL SEEPAGE INTO POND 656J5 1996-1888 FCR MAINTNC 140TH WY SE & MPL SPEC OPS REQUEST 656H5 1996-1988 C DRNG 15605 139TH CT SE FLOW FROM ADJ PROP IMPACT PVT 656H5 1996-2061 R FLDG 14615 SE RENTON-MAPLE 656H4 1997-0054 C FLDG 13660 143RD AVE SE GROUNDWATER FROM NEIGHBOR 656H4 1997-0248 C DRNG 13970 SE 159TH PL SHEET FLOW ON RD DRNG ISSUE 656H5 1997-0255 C RUNOFF 15805 140TH CT SE BLOCKED DRAINAGE OVERFLOW ON 656H5 1997-0349 C FLDG 138DD SE 156TH PONDING IN ROAD RIGHT-OF-WAY 656H5 1997-0514 C DRAINAGE 15816 140TH CT SE SUBSTANDARD LOT CONST IMPACT TO 656H5 1997-0514 R DRAINAGE 15816 140TH CT SE SUBSTANDARD LOT CONST IMPACT TO 656H5 1998-0551 C DRAINAGE 14610 142ND AVE SE ROAD DRNG INADEQUATE OFF RD 656H4 1998-0551 NDA DRAINAGE 14610 142ND AVE SE ROAD DRNG INADEQUATE OFF RD 656H4 1998-0551 R DRAINAGE 14610 142ND AVE SE ROAD DRNG INADEQUATE OFF RD 656H4 2000-0700 C DCA 14645 SE RENTON MAPLE PRIVATE DRAINAGE PROJECT AT 656J5 2001-0378 FCS MNM 14645 RENTON MAPLE CONCERN REGARDING KIDS PLAYING 656J5 2002-0275 FCS MNM 14900 RENTON MAPLE VALLY No problem found 656J5 2004-0325 WQA WQAI 15031 MAPLE VALLEY HWY WQA FROM MCL REQUEST 656J5 2005-0142 C MMF 14645 RENTON-MAPLE Ditch backing up onto Wonderland Estates 656J5 2005-0142 R MMF 14645 RENTON-MAPLE Ditch backing up onto Wonderland Estates 656J5 2008-0036 WQC WQI 15417 141ST PL SE Pipe from garage discharges grey water at 656H5 2008-0036 WQR WQI 15417 141ST PL SE Pipe from garage discharges grey water at 656H5 2008-0327 C TRE 14435 141ST PL SE Need to remove 2 cottonwood trees on KC 656H4 2010-0272 C DLE 14235 SE 146TH ST Erosion/landslide. TA provided. 656H4 2010-0730 C RFD 14616 142ND AVE SE Flooding on prop? Previous NDAP on 656H4 2010-0730 R RFD 14616 142ND AVE SE Flooding on prop? Previous NDAP on 656H4 2013-0527 FCS MNM 15900 140TH WY SE Gate broken @ DR0642? Already identified 656J5 2014-0141 C DDM 14609 142ND AVE SE Property drainage discharges onto hillside? 656H4 Exhibit D Level 3 Analysis LEVEL 3 OFF-SITE DRAINAGE ANALYSIS Elliott Farms Renton, Washington Prepared for: Quadrant Homes 15900 S.E. Eastgate Way, Suite 300 Bellevue, WA 98008 August 28, 2020 Our Job No. 21397 21397.003-Level 3.docx TABLE OF CONTENTS 1.0 SUMMARY OF ANALYSIS 2.0 LEVEL 3 ANALYSIS Tab 1.0 21397.003-Level 3.docx SUMMARY OF ANALYSIS A level 3 conveyance analysis has been conducted for the downstream system for Elliott Farms. The downstream system consists two existing conveyance systems that ultimately drain to the existing wetpond built with previous development that was sized in include the drainage from the Elliott Farms project. The proposed Elliott Farms site has been divided into two proposed developed basins D1 and D2. Refer to the Post Developed Drainage Area Map in Section 2. Basin D1 is 1.75 acres in size. The drainage from Basin D1 will discharge westerly through a proposed conveyance system and connect to the existing storm system in Molasses Creek, also referred to as Cedarwood Division 3 in this report. The Molasses Creek conveyance system also receives drainage from Cedarwood Divisions 1 and 2. The drainage is conveyed to a wetpond located at the intersection of SR-169 and 140th Ave SE for water quality treatment then discharges directly to the Cedar River. Basin D2 is 3.52 acres in size. The drainage from basin D2 will discharge at the northwest corner of the site into the existing conveyance ditch along SR-169 which also discharges to the existing wetpond. The SR-169 conveyance system also receives drainage from SR-169 roadway. A backwater analysis was conducted for both downstream paths (Molasses Creek and the SR-169 Roadside Ditch) entering the wet pond and the overflow conveyance system discharging into the Cedar River. The rational method and KCRTS was used to analyze the 100 year peak flows and the King County Backwater Program was used to analyze the capacity of the existing downstream systems. The upstream basins area were obtained from the Hugh Goldsmith & Associates, Inc. TIR dated August 1996. The summary is included in Section 2. Summary of predicted 100 year peak flows: Molasses Creek to wetpond Basin Area (Acres) Q100 year (cfs) D1 1.75 3.08 Cedarwood Division 1, 2 & 3 39.41 24.45 Total 41.16 27.53 SR-169 Conveyance system to wetpond Basin Area (Acres) Q100 year (cfs) D2 3.52 4.61 SR-169 7.84 10.52 SR-169 Culvert (sub basin) 2.80 5.10 Total 11.36 15.13 Wetpond to Cedar River Basin Area (Acres) Q100 year (cfs) Molasses Creek 41.16 27.53 SR-169 Conveyance system 11.36 15.13 Cedarwood Division 4 5.18 6.50 Total 57.70 49.16 The SR-169 Roadside ditch was separated in four sections to analyze the capacity. The first section consisted of all of the SR-169 and Basin D2 tributary area conveyed through the existing 24" culvert crossing 140th Way SE and discharging into the existing wet pond. The second portion is the ditch section with varying depths from 140th Way SE extending to the entrance to Molasses Creek. The third section is the 18-inch culvert crossing under the entrance to Molasses Creek. The fourth 21397.003-Level 3.docx section is the ditch section extending east to the site. The backwater analysis shows that the existing ditch and culverts contain enough capacity to convey the additional developed the Elliott Farms project basin D2. The existing conveyance system in the Molasses Creek development that discharges into the wetpond has sufficient capacity to convey the additional flow from Basin D1 in Elliott Farms. The conveyance system from the wetpond to the Cedar River outfall also contains enough capacity to convey the developed flows from Elliott Farms. In conclusion the existing downstream storm system has sufficient capacity for the additional runoff from the proposed plat of Elliott Farms. Refer to Section 2 for exhibits and calculations. Tab 2.0 ONLYELLIOTT FARMS ELLIOTT FARMS ELLIOTT FARMS ELLIOTT FARMS Molasses Creek Storm Drain Conveyance Analysis ELLIOTT FARMS ELLIOTT FARMS123456789Pipe No.Molasses Creek ONLYELLIOTT FARMS ELLIOTT FARMS1011121314Pipe No.Molasses Creek 21397-Conveyance.xlsBARGHAUSEN CONSULTING ENGINEERS - PIPE FLOW CALCULATORusing the Rational Method & Manning FormulaCITY OF RENTON DESIGN FOR 100YEAR STORMJOB NAME:Elliott Farms Prelim NOTE: ENTER DEFAULTS AND STORM DATA BEFORE BEGINNING JOB#:21397 DEFAULTS C=0.6n=0.013REVISED:8/18/2020 d=30Tc=6.3A= Contributing Area (Ac) Qd= Design Flow (cfs) COEFFICIENTS FOR THE RATIONAL METHOD "Ir"-EQUATIONC= Runoff Coefficient Qf= Full Capacity Flow (cfs)STORMAr BrTc= Time of Concentration (min) Vd= Velocity at Design Flow (fps)2YR 1.58 0.58I= Intensity at Tc (in/hr) Vf= Velocity at Full Flow (fps)10YR 2.44 0.64PRECIP=3.9d= Diameter of Pipe (in) s= Slope of pipe (%)25YR 2.66 0.65Ar=2.61L= Length of Pipe (ft) n= Manning Roughness Coefficient50YR 2.75 0.65Br=0.63D= Water Depth at Qd (in) Tt= Travel Time at Vd (min)100YR 2.61 0.63FROM TO A s Ld Tc n CSUM AA*CSUM A*C I Qd QfQd/QfXD/d D Vf Vd/Vf VdTt====== ====== ====== ====== ================== ====== ============ ===================== ====== ====== ================== ====== ========================CB#1 X3-4A 1.75 0.75 14112 10.0 0.013 0.661.751.161.16 2.39 2.76 3.080.8940.733 8.80 3.93 1.13 4.430.53X3-4A X3-4 0.69 0.92 14012 10.5 0.013 0.62.440.411.57 2.31 3.62 3.421.0610.888 10.65 4.35 1.13 4.920.47X3-4 X3-8 27.59 0.60 14030 20.0 0.013 0.4727.5912.9714.54 1.54 22.41 31.760.7060.620 18.61 6.48 1.09 7.030.33X3-8 X3-10 0.58 0.66 12030 20.3 0.013 0.628.170.3514.88 1.53 22.71 33.310.6820.605 18.14 6.79 1.07 7.290.27X3-10 X3-12 1.18 0.45 15930 20.6 0.013 0.629.350.7115.59 1.51 23.59 27.510.8580.712 21.36 5.61 1.12 6.300.42X3-12 X3-14 0.78 0.67 14230 21.0 0.013 0.630.130.4716.06 1.49 23.99 33.560.7150.626 18.77 6.84 1.09 7.440.32X3-14 X3-16 1.11 0.55 13030 21.3 0.013 0.631.240.6716.73 1.48 24.75 30.410.8140.685 20.56 6.20 1.11 6.900.31X3-16 X3-18 0.83 0.50 13030 21.7 0.013 0.632.070.5017.22 1.47 25.26 28.990.8710.721 21.62 5.91 1.13 6.650.33X3-18 X3-20 1.52 1.00 5630 22.0 0.013 0.633.590.9118.14 1.45 26.35 41.000.6430.588 17.65 8.36 1.06 8.900.10X3-20 X3-25 0.72 0.50 11630 22.1 0.013 0.634.310.4318.57 1.45 26.89 28.990.9280.755 22.65 5.91 1.13 6.680.29X3-25 X3-26 0.99 0.50 11530 22.4 0.013 0.635.30.5919.16 1.44 27.53 28.990.9490.772 23.15 5.91 1.13 6.680.29X3-26 X-6 0.38 0.50 14330 22.7 0.013 0.635.680.2319.39 1.43 27.63 28.990.9530.774 23.23 5.91 1.13 6.680.36X-6 X-5 0.06 0.5 3036 23.0 0.013 0.635.740.0419.43 1.41 27.41 47.150.5810.547 19.67 6.68 1.03 6.910.07X-5 XPOND 0.20 0.50 12436 23.0 0.013 0.635.880.1219.51 1.41 27.53 47.150.5840.548 19.73 6.68 1.04 6.920.30Page 1Molasses Creek BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:p-.bwp Surcharge condition at intermediate junctions Tailwater Elevation:80.97 feet Discharge Range:27.53 to 27.53 Step of 1. [cfs] Overflow Elevation:91.84 feet Weir:NONE Channel Width:1. feet PIPE NO. 1: 124 LF - 36"CP @ 0.50% OUTLET: 74.70 INLET: 75.32 INTYP: 4 JUNC NO. 1: OVERFLOW-EL: 85.92 BEND: 0 DEG DIA/WIDTH: 4.5 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 27.53 5.88 81.20 * 0.012 1.70 1.57 6.27 6.27 5.83 5.88 2.22 PIPE NO. 2: 30 LF - 36"CP @ 0.50% OUTLET: 75.32 INLET: 75.47 INTYP: 4 JUNC NO. 2: OVERFLOW-EL: 85.92 BEND: 5 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.01 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 27.53 5.78 81.25 * 0.012 1.70 1.57 5.88 5.88 5.78 5.60 1.99 PIPE NO. 3: 143 LF - 30"CP @ 0.51% OUTLET: 75.47 INLET: 76.20 INTYP: 4 JUNC NO. 3: OVERFLOW-EL: 86.00 BEND: 15 DEG DIA/WIDTH: 4.5 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 27.26 5.72 81.92 * 0.012 1.79 1.79 5.78 5.78 5.59 5.72 2.28 PIPE NO. 4: 115 LF - 30"CP @ 3.05% OUTLET: 76.20 INLET: 79.71 INTYP: 4 JUNC NO. 4: OVERFLOW-EL: 86.00 BEND: 87 DEG DIA/WIDTH: 4.5 Q-RATIO: 0.02 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 27.26 3.35 83.06 * 0.012 1.79 1.03 5.72 5.72 2.65 3.35 2.81 PIPE NO. 5: 116 LF - 30"CP @ 0.32% OUTLET: 79.71 INLET: 80.08 INTYP: 4 JUNC NO. 5: OVERFLOW-EL: 85.68 BEND: 12 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.02 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 26.72 3.54 83.62 * 0.012 1.77 2.25 3.35 3.35 3.40 3.54 2.30 PIPE NO. 6: 56 LF - 30"CP @ 0.98% OUTLET: 80.13 INLET: 80.68 INTYP: 4 JUNC NO. 6: OVERFLOW-EL: 85.68 BEND: 75 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.04 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 26.20 3.67 84.35 * 0.012 1.75 1.39 3.49 3.49 3.14 3.67 2.65 Molasses Creek Backwater Analysis PIPE NO. 7: 130 LF - 30"CP @ 0.32% OUTLET: 80.68 INLET: 81.09 INTYP: 4 JUNC NO. 7: OVERFLOW-EL: 86.23 BEND: 6 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.02 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 25.19 3.79 84.88 * 0.012 1.72 2.08 3.67 3.67 3.67 3.79 2.22 PIPE NO. 8: 130 LF - 30"CP @ 0.55% OUTLET: 81.09 INLET: 81.81 INTYP: 4 JUNC NO. 8: OVERFLOW-EL: 87.01 BEND: 1 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.03 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 24.70 3.60 85.41 * 0.012 1.70 1.62 3.79 3.79 3.48 3.60 2.20 PIPE NO. 9: 142 LF - 30"CP @ 0.60% OUTLET: 81.91 INLET: 82.76 INTYP: 4 JUNC NO. 9: OVERFLOW-EL: 87.01 BEND: 5 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.02 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 23.98 3.18 85.94 * 0.012 1.67 1.54 3.50 3.50 3.07 3.18 2.17 PIPE NO.10: 159 LF - 30"CP @ 0.44% OUTLET: 82.81 INLET: 83.51 INTYP: 4 JUNC NO.10: OVERFLOW-EL: 88.31 BEND: 3 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.04 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 23.51 3.00 86.51 * 0.012 1.66 1.69 3.13 3.13 2.88 3.00 2.17 PIPE NO.11: 120 LF - 30"CP @ 0.66% OUTLET: 83.56 INLET: 84.35 INTYP: 4 JUNC NO.11: OVERFLOW-EL: 88.71 BEND: 7 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.01 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 22.60 2.54 86.89 * 0.012 1.62 1.44 2.95 2.95 2.45 2.54 2.10 PIPE NO.12: 140 LF - 30"CP @ 0.60% OUTLET: 84.35 INLET: 85.19 INTYP: 4 JUNC NO.12: OVERFLOW-EL: 89.78 BEND: 14 DEG DIA/WIDTH: 5.0 Q-RATIO: 5.18 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 22.38 2.58 87.77 * 0.012 1.61 1.47 2.54 2.54 1.94 2.58 2.47 PIPE NO.13: 140 LF - 12"CP @ 0.92% OUTLET: 86.48 INLET: 87.77 INTYP: 4 JUNC NO.13: OVERFLOW-EL: 89.78 BEND: 9 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.32 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.62 1.50 89.27 * 0.012 0.82 0.80 1.29 1.29 1.24 1.50 1.22 PIPE NO.14: 141 LF - 12"CP @ 0.50% OUTLET: 87.77 INLET: 88.48 INTYP: 4 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 2.74 1.14 89.62 * 0.012 0.72 0.83 1.50 1.50 1.00 1.14 1.01 WA169 Roadside Ditch Conveyance Analysis ELLIOTT FARMS ELLIOTT FARMS12Pipe No.WA169 Roadside DitchDitch section from Molasses CreekEntrance to 140th Way SEEX 24" FROM DITCH ALONGNORTH SIDE OF SR-169 ONLYELLIOTT FARMS ELLIOTT FARMSWA169 Roadside DitchDitch section from Molasses CreekEntrance to 140th Way SECulvert Section at Entranceto Molasses CreekTrench Section fromEntrance to MolassesCreek to Project Site Flow Frequency Analysis LogPearson III Coefficients Time Series File:time series output.tsMean= 0.602 StdDev= 0.160 Project Location:Sea-Tac Skew= 1.343 ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob (CFS) (CFS) Period 5.44 8 2/16/49 17:45 15.13 1 89.50 0.989 7.22 5 3/03/50 15:00 9.29 2 32.13 0.969 3.33 35 8/27/51 18:00 8.34 3 19.58 0.949 3.80 25 10/17/51 7:15 7.50 4 14.08 0.929 2.79 43 9/30/53 3:00 7.22 5 10.99 0.909 3.13 38 12/19/53 17:30 6.48 6 9.01 0.889 2.72 45 7/30/55 21:15 5.60 7 7.64 0.869 4.09 20 10/04/55 10:00 5.44 8 6.63 0.849 3.72 28 12/09/56 12:45 5.35 9 5.86 0.829 3.49 33 1/16/58 10:00 4.78 10 5.24 0.809 4.54 12 10/18/58 19:45 4.71 11 4.75 0.789 4.52 13 10/10/59 22:00 4.54 12 4.34 0.769 3.78 26 2/14/61 20:15 4.52 13 3.99 0.749 3.27 36 8/04/62 13:15 4.47 14 3.70 0.729 3.11 39 12/01/62 20:15 4.41 15 3.44 0.709 2.50 48 6/05/64 15:00 4.30 16 3.22 0.690 3.53 32 4/20/65 19:30 4.24 17 3.03 0.670 2.41 49 1/05/66 15:00 4.13 18 2.85 0.650 4.13 18 11/13/66 17:45 4.09 19 2.70 0.630 8.34 3 8/24/68 15:00 4.09 20 2.56 0.610 3.71 29 10/20/68 12:00 4.07 21 2.44 0.590 2.22 50 1/13/70 20:45 3.89 22 2.32 0.570 2.68 46 12/06/70 7:00 3.88 23 2.22 0.550 5.60 7 12/08/71 17:15 3.84 24 2.13 0.530 3.26 37 4/18/73 9:30 3.80 25 2.04 0.510 3.84 24 11/28/73 8:00 3.78 26 1.96 0.490 4.24 17 8/17/75 23:00 3.78 27 1.89 0.470 2.83 42 10/29/75 7:00 3.72 28 1.82 0.450 2.66 47 8/23/77 14:30 3.71 29 1.75 0.430 4.71 11 9/17/78 1:00 3.62 30 1.70 0.410 6.48 6 9/08/79 13:45 3.56 31 1.64 0.390 4.47 14 12/14/79 20:00 3.53 32 1.59 0.370 4.41 15 9/21/81 8:00 3.49 33 1.54 0.350 9.29 2 10/05/81 22:15 3.45 34 1.49 0.330 3.88 23 10/28/82 16:00 3.33 35 1.45 0.310 2.96 40 1/02/84 23:30 3.27 36 1.41 0.291 2.76 44 6/06/85 21:15 3.26 37 1.37 0.271 4.09 19 10/27/85 10:45 3.13 38 1.33 0.251 4.78 10 10/25/86 22:45 3.11 39 1.30 0.231 3.89 22 5/13/88 17:30 2.96 40 1.27 0.211 3.62 30 8/21/89 16:00 2.93 41 1.24 0.191 5.35 9 1/09/90 5:30 2.83 42 1.21 0.171 3.78 27 4/03/91 20:15 2.79 43 1.18 0.151 2.93 41 1/27/92 15:00 2.76 44 1.15 0.131 3.56 31 6/09/93 12:15 2.72 45 1.12 0.111 3.45 34 11/17/93 16:45 2.68 46 1.10 0.091 4.07 21 6/05/95 17:00 2.66 47 1.08 0.071 WA169 Roadside Ditch Peak Inflow 4.30 16 7/19/96 19:30 2.50 48 1.05 0.051 15.13 1 12/29/96 11:45 2.41 49 1.03 0.031 7.50 4 10/04/97 14:15 2.22 50 1.01 0.011 Computed Peaks 13.15 100.00 0.990 Computed Peaks 10.73 50.00 0.980 Computed Peaks 8.71 25.00 0.960 Computed Peaks 6.54 10.00 0.900 Computed Peaks 6.18 8.00 0.875 Computed Peaks 5.20 5.00 0.800 Computed Peaks 3.69 2.00 0.500 Computed Peaks 3.01 1.30 0.231 BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:Trench Pipe Run 1.bwp Surcharge condition at intermediate junctions Tailwater Elevation:78.84 feet Discharge Range:15.15 to 15.15 Step of 1. [cfs] Overflow Elevation:82.65 feet Weir:NONE Channel Width:1. feet PIPE NO. 1: 25 LF - 24"CP @ 11.00% OUTLET: 75.84 INLET: 78.59 INTYP: 4 JUNC NO. 1: OVERFLOW-EL: 83.84 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 15.15 1.69 80.28 * 0.012 1.41 0.59 3.00 3.00 1.41 ***** 1.69 PIPE NO. 2: 145 LF - 24"CP @ 0.59% OUTLET: 78.59 INLET: 79.45 INTYP: 4 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 15.15 1.41 80.86 * 0.012 1.41 1.36 1.69 1.69 1.41 ***** 1.36 WA169 Roadside Ditch Backwater Analysis Pipe run from ditch to retention pond BACKWATER COMPUTER PROGRAM FOR OPEN CHANNELS Channel Data Filename:Trench Run 1.bwc Tailwater Elevation:82.65 feet Discharge Range:15.15 to 15.15 Step of 1. [cfs] STATION 0.00: INVERT= 82.70 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 8.63 1.83 0.035 * 15.72 1.83 0.035 12.78 2.65 0.035 * 25.81 1.99 0.035 15.51 3.49 0.035 * 34.23 3.49 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN Q-TW TW-HT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 0.90 83.60 * 0.83 0.90 0.00 0.00 0.035 5.39 12.12 2.81 ****REACH NO. 1: LENGTH= 46.17 FT AVG.GRADE= 1.30% **** STATION 46.17: INVERT= 83.30 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 4.14 0.62 0.035 * 10.32 0.62 0.035 6.14 1.05 0.035 * 20.52 1.05 0.035 15.45 3.14 0.035 * 26.28 3.14 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 0.83 84.13 * 0.66 0.00 0.66 0.74 0.035 8.14 20.51 1.86 ****REACH NO. 2: LENGTH= 58.82 FT AVG.GRADE= -0.12% **** STATION 104.99: INVERT= 83.23 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 10.74 2.23 0.035 * 14.61 2.23 0.035 16.70 3.64 0.035 * 19.31 5.64 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 1.21 84.44 * 0.88 0.00 0.88 0.00 0.035 8.32 13.97 1.82 ****REACH NO. 3: LENGTH= 102.68 FT AVG.GRADE= 0.75% **** STATION 207.67: INVERT= 84.00 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES WA169 Roadside Ditch Backwater Analysis Ditch section from Molasses Creek Entrance to 140th Way SE LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 2.78 0.00 0.035 * 4.23 0.00 0.035 4.02 0.35 0.035 * 6.65 0.35 0.035 14.29 3.37 0.035 * 13.43 3.38 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 0.80 84.80 * 0.49 0.00 0.49 0.64 0.035 8.47 13.44 1.79 ****REACH NO. 4: LENGTH= 11.87 FT AVG.GRADE= 0.00% **** STATION 219.54: INVERT= 84.00 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 3.16 0.00 0.035 * 4.40 0.00 0.035 14.99 3.41 0.035 * 12.61 3.41 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 0.84 84.84 * 0.49 0.00 0.49 0.00 0.035 8.42 12.78 1.80 ****REACH NO. 5: LENGTH= 57.10 FT AVG.GRADE= -0.33% **** STATION 276.64: INVERT= 83.81 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 1.93 0.06 0.035 * 1.77 0.00 0.035 6.14 3.76 0.035 * 10.01 3.76 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 1.20 85.01 * 0.77 0.00 0.77 0.00 0.035 6.70 8.32 2.26 ****REACH NO. 6: LENGTH= 60.37 FT AVG.GRADE= 0.84% **** STATION 337.01: INVERT= 84.32 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 10.29 3.44 0.035 * 7.67 3.77 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 1.53 85.85 * 1.22 1.53 1.22 1.43 0.035 5.88 8.29 2.58 ****REACH NO. 7: LENGTH= 101.39 FT AVG.GRADE= 0.58% **** STATION 438.40: INVERT= 84.91 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 9.89 3.62 0.035 * 6.66 3.62 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 1.78 86.69 * 1.26 1.78 1.26 1.60 0.035 7.24 8.91 2.09 ****REACH NO. 8: LENGTH= 185.44 FT AVG.GRADE= 0.33% **** STATION 623.84: INVERT= 85.52 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 0.88 0.04 0.035 * 1.77 0.07 0.035 5.81 2.57 0.035 * 7.27 2.57 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 1.64 87.16 * 0.89 1.41 0.89 1.37 0.035 9.47 9.95 1.60 ****REACH NO. 9: LENGTH= 164.56 FT AVG.GRADE= 0.29% **** STATION 788.40: INVERT= 86.00 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 1.15 0.00 0.035 * 1.40 0.02 0.035 5.15 1.92 0.035 * 7.46 1.92 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 15.15 1.44 87.44 * 0.83 0.00 0.83 1.31 0.035 9.03 10.62 1.68 Flow Frequency Analysis LogPearson III Coefficients Time Series File:cul.tsf Mean= 0.119 StdDev= 0.162 Project Location:Sea-Tac Skew= 1.365 ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob (CFS) (CFS) Period 1.81 8 2/16/49 17:45 5.10 1 89.50 0.989 2.42 5 3/03/50 15:00 3.10 2 32.13 0.969 1.08 35 8/27/51 18:00 2.77 3 19.58 0.949 1.25 27 10/17/51 7:15 2.50 4 14.08 0.929 0.909 43 9/30/53 3:00 2.42 5 10.99 0.909 1.03 38 12/19/53 17:30 2.11 6 9.01 0.889 0.881 46 7/30/55 21:15 1.86 7 7.64 0.869 1.32 20 10/04/55 10:00 1.81 8 6.63 0.849 1.24 28 12/09/56 12:45 1.80 9 5.86 0.829 1.15 33 1/16/58 10:00 1.56 10 5.24 0.809 1.48 14 10/18/58 19:45 1.54 11 4.75 0.789 1.49 12 10/10/59 22:00 1.49 12 4.34 0.769 1.25 25 2/14/61 20:15 1.48 13 3.99 0.749 1.06 36 8/04/62 13:15 1.48 14 3.70 0.729 1.02 39 12/01/62 20:15 1.43 15 3.44 0.709 0.810 48 6/05/64 15:00 1.39 16 3.22 0.690 1.17 32 4/20/65 19:30 1.37 17 3.03 0.670 0.794 49 1/05/66 15:00 1.36 18 2.85 0.650 1.36 18 11/13/66 17:45 1.34 19 2.70 0.630 2.77 3 8/24/68 15:00 1.32 20 2.56 0.610 1.22 29 10/20/68 12:00 1.32 21 2.44 0.590 0.730 50 1/13/70 20:45 1.27 22 2.32 0.570 0.882 45 12/06/70 7:00 1.27 23 2.22 0.550 1.86 7 12/08/71 17:15 1.26 24 2.13 0.530 1.06 37 4/18/73 9:30 1.25 25 2.04 0.510 1.27 23 11/28/73 8:00 1.25 26 1.96 0.490 1.37 17 8/17/75 23:00 1.25 27 1.89 0.470 0.933 42 10/29/75 7:00 1.24 28 1.82 0.450 0.862 47 8/23/77 14:30 1.22 29 1.75 0.430 1.54 11 9/17/78 1:00 1.18 30 1.70 0.410 2.11 6 9/08/79 13:45 1.17 31 1.64 0.390 1.48 13 12/14/79 20:00 1.17 32 1.59 0.370 1.43 15 9/21/81 8:00 1.15 33 1.54 0.350 3.10 2 10/05/81 22:15 1.12 34 1.49 0.330 1.27 22 10/28/82 16:00 1.08 35 1.45 0.310 0.973 40 1/02/84 23:30 1.06 36 1.41 0.291 0.903 44 6/06/85 21:15 1.06 37 1.37 0.271 1.34 19 10/27/85 10:45 1.03 38 1.33 0.251 1.56 10 10/25/86 22:45 1.02 39 1.30 0.231 1.26 24 5/13/88 17:30 0.973 40 1.27 0.211 1.18 30 8/21/89 16:00 0.965 41 1.24 0.191 1.80 9 1/09/90 5:30 0.933 42 1.21 0.171 1.25 26 4/03/91 20:15 0.909 43 1.18 0.151 0.965 41 1/27/92 15:00 0.903 44 1.15 0.131 1.17 31 6/09/93 12:15 0.882 45 1.12 0.111 1.12 34 11/17/93 16:45 0.881 46 1.10 0.091 1.32 21 6/05/95 17:00 0.862 47 1.08 0.071 WA169 Roadside Ditch Peak Inflow into Culvert 1.39 16 7/19/96 19:30 0.810 48 1.05 0.051 5.10 1 12/29/96 11:45 0.794 49 1.03 0.031 2.50 4 10/04/97 14:15 0.730 50 1.01 0.011 Computed Peaks 4.42 100.00 0.990 Computed Peaks 3.59 50.00 0.980 Computed Peaks 2.90 25.00 0.960 Computed Peaks 2.17 10.00 0.900 Computed Peaks 2.04 8.00 0.875 Computed Peaks 1.71 5.00 0.800 Computed Peaks 1.21 2.00 0.500 Computed Peaks 0.985 1.30 0.231 BACKWATER PROGRAM FOR ROUND/ARCH CULVERTS Tailwater Elevation:85.58 feet Discharge Range:5.1 to 5.1 Step of 1. [cfs] Overflow Elevation:89.2 feet Weir:NONE Channel Width:1.5 feet CULV NO. 1: 286 LF - 18"CP @ 0.27% OUTLET: 85.58 INLET: 86.36 INTYP: 4 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 5.10 1.23 87.59 * 0.012 0.87 1.08 0.00 0.87 1.08 1.23 1.16 WA169 18" Culvert Backwater Analysis Culvert Section at Entrance to Molasses Creek BACKWATER COMPUTER PROGRAM FOR OPEN CHANNELS Channel Data Filename:Trench Run 2.bwc Tailwater from HW/TW File:Culvert.bwt Discharge Range:5.1 to 5.1 Step of 1. [cfs] STATION 0.00: INVERT= 86.71 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 1.21 0.03 0.035 * 1.24 0.00 0.035 6.56 2.28 0.035 * 6.70 2.31 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN Q-TW TW-HT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 5.10 0.88 87.59 * 0.47 0.00 5.10 0.88 0.035 3.91 6.90 1.30 ****REACH NO. 1: LENGTH= 34.26 FT AVG.GRADE= -0.06% **** STATION 34.26: INVERT= 86.69 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 1.56 0.07 0.035 * 1.11 0.00 0.035 6.97 2.37 0.035 * 8.59 2.37 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 5.10 0.97 87.66 * 0.46 0.00 0.46 0.00 0.035 4.97 8.18 1.03 ****REACH NO. 2: LENGTH= 13.63 FT AVG.GRADE= 0.59% **** STATION 47.89: INVERT= 86.77 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 1.62 0.00 0.035 * 1.48 0.10 0.035 7.69 2.65 0.035 * 5.90 2.65 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 5.10 0.91 87.68 * 0.45 0.58 0.45 0.65 0.035 4.26 7.00 1.20 ****REACH NO. 3: LENGTH= 13.40 FT AVG.GRADE= 0.90% **** STATION 61.29: INVERT= 86.89 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR WA169 Roadside Ditch Backwater Analysis Trench Section from Entrance to Molasses Creek to Project Site 1.81 0.00 0.035 * 1.57 0.11 0.035 7.29 2.36 0.035 * 8.95 2.36 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 5.10 0.82 87.71 * 0.43 0.56 0.43 0.55 0.035 4.29 7.89 1.19 ****REACH NO. 4: LENGTH= 61.34 FT AVG.GRADE= 0.83% **** STATION 122.63: INVERT= 87.40 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 2.50 0.16 0.035 * 2.18 0.00 0.035 9.31 2.26 0.035 * 8.25 2.26 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 5.10 0.60 88.00 * 0.38 0.60 0.38 0.50 0.035 3.41 7.90 1.50 ****REACH NO. 5: LENGTH= 91.58 FT AVG.GRADE= 0.40% **** STATION 214.21: INVERT= 87.77 FT EC=1.15 Q-RATIO=0.00 CROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES LEFT(FT) STAGE(FT) N-FACTOR * RIGHT(FT) STAGE(FT) N-FACTOR 1.75 0.00 0.035 * 0.80 0.11 0.035 3.22 0.08 0.035 * 2.55 0.84 0.035 8.34 1.21 0.035 * 3.24 1.21 0.035 11.44 2.19 0.035 * 5.03 2.18 0.035 Q(CFS) Y1(FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Y1 A-Y1 WP-Y1 V-Y1 ******************************************************************************* 5.10 0.62 88.39 * 0.40 0.00 0.40 0.62 0.035 3.36 7.86 1.52 File Opened for Writing:trench2.bwt Save results to HW/TW file:trench2.bwt File Opened for Writing:trench2.RS1 Save results to Routing file:trench2.RS1 File Opened for Writing:trench2.bwt Save results to HW/TW file:trench2.bwt File Opened for Writing:trench2.RS1 Save results to Routing file:trench2.RS1 Cedar River Storm Drain Discharge Conveyance Analysis ELLIOTT FARMS ELLIOTT FARMS2Pipe No.Cedar River Discharge1 Flow Frequency Analysis LogPearson III Coefficients Time Series File:division 4.tsf Mean= 0.201 StdDev= 0.168 Project Location:Sea-Tac Skew= 1.401 ---Annual Peak Flow Rates--- -----Flow Frequency Analysis------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob (CFS) (CFS) Period 2.24 9 2/16/49 17:45 6.50 1 89.50 0.989 3.04 5 3/03/50 15:00 3.86 2 32.13 0.969 1.26 35 8/27/51 18:00 3.41 3 19.58 0.949 1.51 27 10/17/51 7:15 3.14 4 14.08 0.929 1.08 44 9/30/53 3:00 3.04 5 10.99 0.909 1.25 37 12/19/53 17:30 2.50 6 9.01 0.889 1.03 46 11/25/54 1:00 2.32 7 7.64 0.869 1.55 21 10/04/55 10:00 2.29 8 6.63 0.849 1.54 23 12/09/56 12:45 2.24 9 5.86 0.829 1.41 32 1/16/58 10:00 1.86 10 5.24 0.809 1.78 14 10/18/58 19:45 1.84 11 4.75 0.789 1.82 13 10/10/59 22:00 1.82 12 4.34 0.769 1.53 26 2/14/61 20:15 1.82 13 3.99 0.749 1.24 38 8/04/62 13:15 1.78 14 3.70 0.729 1.24 39 12/01/62 20:15 1.68 15 3.44 0.709 0.956 49 6/05/64 15:00 1.67 16 3.22 0.690 1.45 30 4/20/65 19:30 1.66 17 3.03 0.670 0.961 48 1/05/66 15:00 1.62 18 2.85 0.650 1.67 16 11/13/66 17:45 1.61 19 2.70 0.630 3.41 3 8/24/68 15:00 1.56 20 2.56 0.610 1.48 29 10/20/68 12:00 1.55 21 2.44 0.590 0.884 50 1/13/70 20:45 1.55 22 2.32 0.570 1.07 45 12/06/70 7:00 1.54 23 2.22 0.550 2.32 7 12/08/71 17:15 1.54 24 2.13 0.530 1.26 36 4/18/73 9:30 1.54 25 2.04 0.510 1.55 22 11/28/73 8:00 1.53 26 1.96 0.490 1.61 19 8/17/75 23:00 1.51 27 1.89 0.470 1.14 42 10/29/75 7:00 1.48 28 1.82 0.450 1.01 47 8/23/77 14:30 1.48 29 1.75 0.430 1.82 12 9/17/78 1:00 1.45 30 1.70 0.410 2.50 6 9/08/79 13:45 1.43 31 1.64 0.390 1.84 11 12/14/79 20:00 1.41 32 1.59 0.370 1.68 15 9/21/81 8:00 1.38 33 1.54 0.350 3.86 2 10/05/81 22:15 1.31 34 1.49 0.330 1.54 25 10/28/82 16:00 1.26 35 1.45 0.310 1.19 40 1/02/84 23:45 1.26 36 1.41 0.291 1.09 43 6/06/85 21:15 1.25 37 1.37 0.271 1.62 18 10/27/85 10:45 1.24 38 1.33 0.251 1.86 10 10/25/86 22:45 1.24 39 1.30 0.231 1.48 28 5/13/88 17:30 1.19 40 1.27 0.211 1.38 33 8/21/89 16:00 1.17 41 1.24 0.191 2.29 8 1/09/90 5:30 1.14 42 1.21 0.171 1.54 24 4/03/91 20:15 1.09 43 1.18 0.151 1.17 41 1/27/92 15:00 1.08 44 1.15 0.131 1.43 31 6/09/93 12:15 1.07 45 1.12 0.111 1.31 34 11/17/93 16:45 1.03 46 1.10 0.091 1.56 20 6/05/95 17:00 1.01 47 1.08 0.071 Division 4 Peak Inflow 1.66 17 5/19/96 11:30 0.961 48 1.05 0.051 6.50 1 12/29/96 11:45 0.956 49 1.03 0.031 3.14 4 10/04/97 14:15 0.884 50 1.01 0.011 Computed Peaks 5.63 100.00 0.990 Computed Peaks 4.52 50.00 0.980 Computed Peaks 3.62 25.00 0.960 Computed Peaks 2.66 10.00 0.900 Computed Peaks 2.51 8.00 0.875 Computed Peaks 2.09 5.00 0.800 Computed Peaks 1.46 2.00 0.500 Computed Peaks 1.18 1.30 0.231 OUTFLOW FROM WETPOND TO CEDAR RIVER BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:21397-out.bwp Surcharge condition at intermediate junctions Tailwater Elevation:78.1 feet Discharge Range:50. to 50. Step of 1. [cfs] Overflow Elevation:82.62 feet Weir:NONE Channel Width:3.5 feet PIPE NO. 1: 180 LF - 36"CP @ 0.08% OUTLET: 75.10 INLET: 75.24 INTYP: 5 JUNC NO. 1: OVERFLOW-EL: 88.79 BEND: 10 DEG DIA/WIDTH: 6.0 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 50.00 4.49 79.73 * 0.012 2.31 3.00 3.00 3.00 3.72 4.49 3.60 PIPE NO. 2: 94 LF - 42"CP @ 0.67% OUTLET: 75.49 INLET: 76.12 INTYP: 5 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 50.00 4.26 80.38 * 0.012 2.22 1.88 4.24 4.24 3.81 4.26 3.23 From overflow structure to discharge location ELLIOTT FARMS ELLIOTT FARMSSCALE: 1"=200' ñt --l -t -! ; -t Section IV Retention/Detention Analysis and Design -¡ -t -.¡ lV, Retention/Detention Analysis and Deslgn Detention is not applicable to this site Water quality facility has been sized for ultimate build-out of site and includes a portion of SR- 169. The design is as follows: Purpose: To determine the required size of a wetpond for the fully developed condition of Cedan¡vood and the tributary drainage area to the existing W.S.D.O.T. detention facility using the new King County S.W.M. Manual (interim). Division 1: Single Family Area = 10.50 ac., 40 lots + 3.8 DU/Ac. = 40/" lmp. lmp. = 4.20 ac. Perv. = 6.3 ac. Division 2: Single Family Area = 14.65 10.65 ac. single family, 56 lots + 5.3 DU/Ac. = 49"/o lmp. lmP. = 5.22 ac' Perv. = 5.43 ac. 4.00 ac. forested Division 3: Multi-family Area = 14.26 ac. 9.22 ac. multi-family lmP. = 5.40 ac. Perv. = 3.82 ac. 5.04 ac. forested Division 4: Multi-family Area = 5.18 ac. lmP. = 2.70 ac. Perv. = 2.48 ac. W.S.D.O.T. Tributary Area: Area = 7.84 ac. 5.00 ac. road 2.89 ac. long grass Totals: lmpervious Area = 22.50 ac. Till Grass = 18.03 ac. Till Forest = 9.04 ac. Outwash = 2.84 ac. r94057q1.445 Page 6l of I l8 HGG Inc. October l, 1996 Hugh G. Goldsmith & Associates,Inc. AREA TRIBUTARY TO MOLASSES CREEK CONVEYANCE SYSTEM " - 0.9(22.50) + 0.25(18.03) + 0.10(9.0a) + 0.01 (2.8a) = 0.49 52.43 VbA/r = 3 R = 0.47 v, = + R Ad c[ry) = 3(0.47)(s2.4s)(.4e)f€iïo) = rc' ,s00 cu.rt. Volume Required = 131,500 cu.ft. Volume Provided = 132,000 cu.ft. ê4057ú.445 Page 62 of ll8 HGG Inc. Octobor l, 1996 Hugh G. Goldsmith & Associates,Inc. Tab 4.0 21397.002-TIR 4.0 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN A. Existing Site Hydrology The on-site topography is generally flat with a steep slope in the southwest corner of the site. The southwest corner of the site contains a wetland with a 50’ buffer that will remain undisturbed. The on-site area draining to the wetland is approximately 1.76 acres and gently slopes toward the wetland. The remaining portion of the site drains into the roadside ditch along WA-169, where flows are conveyed west to the existing wetpond. On-site soils are mapped as Newberg (till soils). The elevations on the site range from 87 to 107. There is an existing drainage ditch along the east side of the project that conveys off-site upstream flows from the southeast to the ditch along WA-169. From here flows are directed across to the north side WA-169 through an existing 18-inch culvert. The off-site upstream basin is shown as OS2 in the upstream/Downstream Drainage Area map and contains approximately 17.2 acres. The majority of the basin area is forested, however approximately 1.0 acres is a single family residence. B. Developed Site Hydrology The proposed on-site road will utilize vertical curb and gutter with depressed curb and sidewalk at driveway connections. The road will connect to the existing 140th Way S.E that was stubbed to the property by Molasses Creek. Catch basins and storm pipes will be installed to convey flows from the new roadway and rooftops to the existing conveyance systems in Molasses Creek and along WA-169. Frontage improvements along WA-169 are required, including, new curb and gutter, sidewalk, and planter strip. The project is proposing to replace the existing ditch with a 24- inch piped conveyance system along the frontage to convey the runoff from WA-169 and a portion of the site to the existing ditch along Molasses creek frontage. The project will be constructing an 18-inch bypass system along the easterly boundary of the site to collect and convey upstream basin OS2 to its natural discharge location. The project will be reducing the amount of area flowing to the wetland at the southwest corner of the site. Please refer to the wetland drainage area map included in Section 1.0 for a breakdown of the land use areas. The pre-developed area (PW1) currently draining to the wetland is approximately 6.98 acres. The post developed area draining to the wetland (DW1) will be approximately 6.54 acres. The diverted area is 6.3% of the total basin area to the wetland. To maintain hydrology to the wetland, the rooftops from lots 44- 45 and the backyards of lots 41-43 will drain to the wetland. Please refer to the WWHM2012 Wetland Hydrology calculations located at the end of this section showing that the developed project will closely match the wetland input volumes in the pre-developed condition. The project will not be providing any form of on-site water quality or flow control. The Elliott Farms project will be utilizing the existing water quality facility that was sized to include this project and built with previous development along with the direct discharge exemption to the Cedar River. Basin D1, as shown on the Post-Developed Drainage Area Map within this section, will drain to the existing conveyance system in Molasses Creek. The developed area will consist of approximately 70% impervious area which includes the proposed roadway and rooftops. 21397.002-TIR.docx Basin D2 will drain to the proposed 24-inch conveyance system installed along the frontage of WA-169. The developed area includes impervious areas from the proposed roadway, a portion of the WA-169 (half street), and rooftops. An open space and park area is proposed in the center of the project. The developed basin can be broken down as follows: Basin D1: Total Area = 2.08 acres Impervious area = 1.31 acres Till grass = 0.77 acres Basin D2: Total Area = 2.98 acres Impervious area = 1.69 acres Till grass = 1.29 acres. C. Performance Standards The project is exempt from flow control requirements based on the direct discharge exemption in core requirement no. 3 of the 2009 KCSWDM and the 2010 City of Renton Amendments to the KCSWDM. The flowpath from the project site discharge point to the edge of the 100-year floodplain of the Cedar River is no longer than one-half mile. The project is subject to Basic Water Quality treatment as allowed in Core Requirement no. 8 because the project drains to a major receiving water. The wetpond provided by previous development was sized using the 1998 KCSWD. The 2009 KCSWD and 2010 Renton amendment still use the same water quality sizing calculations. Based on the sizing calculations found in the Hugh Goldsmith & Associates, Inc, Memorandum included in this section, the Elliott Farms project was allocated 19,000 c.f. of storage for water quality treatment in the existing wetpond. D. Flow Control System Flow Control is exempt for this this project as stated above. E. Water Quality System An existing Wetpond sized for basic water quality treatment will be used for water quality treatment. The existing wetpond was built with previous development and allocated water quality storage for this project. Refer to the Hugh G. Goldsmith & Associates, Inc memorandum dated November 13, 2001 in this section. The wetpond is located at the SWC of the WA-169 and 140th Ave SE intersection. To check the existing capacity of the existing wetpond, an aerial photo was overlaid onto the LIDAR contour map to verify if the existing wetpond matched the dimensions of the Hugh G. Goldsmith & Associates Inc Consulting Engineers plans within this section. Based on the LIDAR and aerial photo, the approximate volume was calculated to be approximately 199,000 c.f which exceeds the the required volume of 188,020 c.f. The wetpond was originally sized for several divisions of the Cedarwood projects, Molasses Creek, areas of the WSDOT right-of way, and this Elliott Farms project. As identified in the Hugh G. Goldsmith Memorandum, the wetpond contains 28,748 cubic feet of extra storage. The Elliott Farms project only requires 16,384 cubic feet of storage based on the Wetpool Sizing Worksheet found in this section. WETPOND SIZING DRAINAGE AREA MAP 1920212223242526272829303132343536373839404142434445213481817161514ONLY65910111213733ONLYONLYIN COMPLIANCE WITH CITY OF RENTON STANDARDSTED QUADRANT HOMES(425) 455-290015900 SE EASTGATE WAY. SUITE 300BELLEVUE, WA 98008ELLIOTT FARMS LUA:C:ELLIOTT FARMS PR:ELLIOTT FARMS”SCALE: 1"=50' Wetpool Sizing Worksheet Wetpool Sizing Worksheet Summary of the Surface Water Design Manual Requirements Project Name:Elliot Farm Project Number:21397 Step 1) Determine volume factor f. Basic size f= 3 Large size f= 4.5 Step 2) Determine rainfall R for mean annual Storm Detemine rainfall R for mean annual storm Rainfall.0.039 (feet) Step 3) Calculate runoff from mean annual storm Vr = (0.9Ai + 0.25Atg + 0.10Atf + 0.01Aog) X R Ai = tributary area of impervious surface 130,645 (sf) Atg = tributary area of till grass 89,801 (sf) Atf = tributary area of till forest 0 (sf) Aog = tributary area of outwash grass 0 (sf) R = rainfall from mean annual storm 0.039 (feet) Vr = Volume of runoff from mean annual storm 5,461 (cf) Step 4) Calculate wetpool Volume Vb = f Vr f = Volume Factor 3 Vr = Volume runoff, mean annual atorm 5,461 (cf) Vb = Volume of the wetpool 16,384 (cf) NEW 12" SD CONNECTION FROM ELLIOTT FARM EXISTING 30-INCH SD TO EXISTING WATER QUALITY POND TOTAL LENGTH FROM CONNECTION POINT OF THE EXISTING 30-INCH SD TO THE OUTFALL AT THE CEDAR RIVER IS 2,320 LF. Wetpool Sizing WorksheetWetland Hydrology Calculations WWHM2012 PROJECT REPORT WETLAND HYDROLOGY 21397-Wetland 2/23/2021 8:13:51 AM Page 2 General Model Information Project Name:21397-Wetland Site Name:Elliott Farm Site Address:SR169 City:Renton Report Date:2/23/2021 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2018/03/02 Version:4.2.14 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year 21397-Wetland 2/23/2021 8:13:51 AM Page 3 Landuse Basin Data Predeveloped Land Use PW1 Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Steep 3.84 C, Pasture, Flat 1.4 Pervious Total 5.24 Impervious Land Use acre POND 1.74 Impervious Total 1.74 Basin Total 6.98 Element Flows To: Surface Interflow Groundwater 21397-Wetland 2/23/2021 8:13:51 AM Page 4 Mitigated Land Use DW1 Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Steep 3.84 C, Pasture, Flat 0.77 C, Lawn, Flat 0.09 Pervious Total 4.7 Impervious Land Use acre ROOF TOPS FLAT 0.06 DRIVEWAYS FLAT 0.04 POND 1.74 Impervious Total 1.84 Basin Total 6.54 Element Flows To: Surface Interflow Groundwater 21397-Wetland 2/23/2021 8:13:51 AM Page 5 Routing Elements Predeveloped Routing 21397-Wetland 2/23/2021 8:13:51 AM Page 6 Mitigated Routing 21397-Wetland 2/23/2021 8:13:52 AM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:5.24 Total Impervious Area:1.74 Mitigated Landuse Totals for POC #1 Total Pervious Area:4.7 Total Impervious Area:1.84 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.79554 5 year 1.045466 10 year 1.220526 25 year 1.453107 50 year 1.634897 100 year 1.824194 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.823363 5 year 1.074674 10 year 1.249783 25 year 1.481473 50 year 1.661913 100 year 1.849271 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 1.119 1.151 1950 0.991 1.019 1951 0.805 0.817 1952 0.567 0.581 1953 0.517 0.548 1954 0.674 0.697 1955 0.729 0.736 1956 0.685 0.714 1957 0.906 0.932 1958 0.628 0.655 21397-Wetland 2/23/2021 8:14:29 AM Page 8 1959 0.563 0.596 1960 0.878 0.883 1961 0.729 0.753 1962 0.530 0.559 1963 0.701 0.725 1964 0.631 0.658 1965 0.840 0.874 1966 0.601 0.619 1967 1.039 1.057 1968 0.925 0.984 1969 0.730 0.766 1970 0.773 0.799 1971 0.846 0.883 1972 0.949 0.981 1973 0.550 0.564 1974 0.775 0.810 1975 0.949 0.971 1976 0.705 0.722 1977 0.565 0.597 1978 0.701 0.737 1979 0.945 1.001 1980 1.251 1.260 1981 0.803 0.835 1982 1.271 1.303 1983 0.798 0.847 1984 0.590 0.614 1985 0.710 0.753 1986 0.888 0.895 1987 0.928 0.984 1988 0.562 0.594 1989 0.702 0.742 1990 1.994 1.986 1991 1.372 1.403 1992 0.624 0.637 1993 0.473 0.487 1994 0.468 0.495 1995 0.695 0.726 1996 1.085 1.076 1997 0.851 0.866 1998 0.661 0.689 1999 1.334 1.426 2000 0.788 0.818 2001 0.723 0.766 2002 1.004 1.043 2003 0.940 0.954 2004 1.375 1.445 2005 0.810 0.827 2006 0.720 0.734 2007 1.673 1.674 2008 1.465 1.472 2009 0.979 0.992 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 1.9944 1.9858 2 1.6727 1.6744 3 1.4646 1.4716 21397-Wetland 2/23/2021 8:14:29 AM Page 9 4 1.3753 1.4454 5 1.3724 1.4260 6 1.3344 1.4033 7 1.2713 1.3033 8 1.2514 1.2598 9 1.1191 1.1514 10 1.0847 1.0761 11 1.0390 1.0573 12 1.0036 1.0434 13 0.9910 1.0192 14 0.9789 1.0010 15 0.9488 0.9919 16 0.9486 0.9843 17 0.9452 0.9836 18 0.9404 0.9814 19 0.9277 0.9708 20 0.9245 0.9542 21 0.9056 0.9321 22 0.8877 0.8953 23 0.8784 0.8834 24 0.8507 0.8833 25 0.8461 0.8745 26 0.8402 0.8660 27 0.8103 0.8467 28 0.8055 0.8354 29 0.8025 0.8271 30 0.7982 0.8184 31 0.7875 0.8173 32 0.7754 0.8097 33 0.7733 0.7993 34 0.7299 0.7663 35 0.7293 0.7656 36 0.7290 0.7535 37 0.7233 0.7531 38 0.7201 0.7422 39 0.7099 0.7374 40 0.7049 0.7364 41 0.7019 0.7339 42 0.7012 0.7256 43 0.7010 0.7252 44 0.6947 0.7218 45 0.6852 0.7139 46 0.6743 0.6969 47 0.6609 0.6886 48 0.6313 0.6579 49 0.6277 0.6547 50 0.6243 0.6370 51 0.6011 0.6192 52 0.5897 0.6144 53 0.5671 0.5975 54 0.5650 0.5955 55 0.5634 0.5937 56 0.5616 0.5806 57 0.5500 0.5640 58 0.5305 0.5589 59 0.5174 0.5480 60 0.4727 0.4953 61 0.4685 0.4867 21397-Wetland 2/23/2021 8:14:29 AM Page 10 21397-Wetland 2/23/2021 8:14:40 AM Page 16 Appendix Predeveloped Schematic 21397-Wetland 2/23/2021 8:14:40 AM Page 17 Mitigated Schematic 21397-Wetland 2/23/2021 8:14:41 AM Page 29 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. 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Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com Tab 5.0 21397.002-TIR.docx 5.0 CONVEYANCE SYSTEM ANALYSIS AND DESIGN The on-site Conveyance system analysis and backwater calculations for the proposed conveyance system is provided in this section. A 100-year conveyance analysis was performed on the existing conveyance system through Molasses Creek to the existing wetpond. See Level 3 analysis in Section 3.0 of this TIR. The existing system has enough capacity for the predicted developed flows from the Elliott Farms project. The proposed conveyance system for this project is curb, gutter, catch basins, and storm drainage pipe. The majority of the storm drainage pipe used will consist of smooth-walled corrugated polyethylene pipe with a Manning's roughness coefficient of 0.12. A 100-year conveyance calculation for the pipes has been completed using the Rational Method. The following are the parameters that were used for final design of the conveyance pipes: 1. A Runoff Coefficient – ‘C’ value was calculated from the 2009 KCSWDM for each tributary area pursuant to table 3.2.1.A. 2. A 100-year/24-hour precipitation of 3.9 inches in accordance with Figure 3.2.1D. 3. A starting time of concentration of 6.3. 4. An "n" factor of 0.012. The tributary areas were calculated as shown on the Catch Basin Area Map within this section for each of the catch basins connecting to the proposed piping system. A 100-year backwater was performed to determine the hydraulic grade line and to see if any catch basin rims overtop. The backwater was performed on the major pipe runs and computer printouts are included within this section. The design flows are based on the rational method. The results show that all the pipes safely convey the 100 year developed flows without over topping any of the rims of the catch basins. 21397-100YR.xlsBARGHAUSEN CONSULTING ENGINEERS - PIPE FLOW CALCULATORusing the Rational Method & Manning FormulaKING COUNTY DESIGN FOR 100YEAR STORMJOB NAME:Elliott Farms NOTE: ENTER DEFAULTS AND STORM DATA BEFORE BEGINNING JOB#:21397 DEFAULTSC=0.9n=0.014FILE NO.:21397-100yr d=12Tc=6.3A= Contributing Area (Ac)Qd= Design Flow (cfs)COEFFICIENTS FOR THE RATIONAL METHOD "Ir"-EQUATIONC= Runoff Coefficient Qf= Full Capacity Flow (cfs)STORMAr BrTc= Time of Concentration (min)Vd= Velocity at Design Flow (fps)2YR1.580.58I= Intensity at Tc (in/hr) Vf= Velocity at Full Flow (fps)10YR 2.44 0.64PRECIP=3.9d= Diameter of Pipe (in) s= Slope of pipe (%)25YR 2.66 0.65Ar=2.61L= Length of Pipe (ft)n= Manning Roughness Coefficient50YR2.750.65Br=0.63D= Water Depth at Qd (in)Tt= Travel Time at Vd (min)100YR2.610.63FROM TO A s Ld Tc n CSUM AA*CSUM A*C I Qd QfQd/QfD/d D Vf VdTt=================================================================================================================================CB#15CB#140.420.5019126.30.0140.730.420.310.313.190.982.340.4190.4525.432.982.860.11CB#14CB#120.080.5099126.40.0140.810.50.060.373.161.172.340.5010.5016.012.983.000.55CB#13CB#120.190.5019126.30.0140.730.190.140.143.190.442.340.1890.2913.502.982.280.14CB#12CB#110.050.5052127.00.0140.780.050.040.563.001.682.340.7180.6277.532.983.240.27CB#11CB#90.060.5035127.20.0140.650.110.040.602.931.752.340.7500.6467.752.983.270.18CB#10CB#90.150.5019126.30.0140.730.150.110.113.190.352.340.1490.2603.122.982.130.15CB#9CB#70.020.5051127.40.0140.580.020.010.732.882.102.340.8980.7368.832.983.360.25CB#8CB#70.230.5027126.30.0140.520.230.120.123.190.382.340.1630.2713.252.982.190.21CB#7CB#50.040.5080157.70.0140.690.040.030.892.822.514.240.5910.5528.283.463.590.37CB#6CB#50.340.5018126.30.0140.660.340.220.223.190.722.340.3060.3774.522.982.610.11CB#5CB#40.050.5061158.03050.0140.620.050.031.162.743.194.240.7510.6469.703.463.800.27CB#4CB#20.030.5053158.30.0140.670.080.021.182.683.174.240.7490.6459.673.463.790.23CB#3CB#20.040.5019126.30.0140.870.040.030.033.190.112.340.0480.1501.802.981.510.21CB#2CB#10.030.5053158.5310.0140.90.030.031.252.643.294.240.7760.6619.913.463.820.23CB#1EX CB0.010.50103158.80.0140.90.040.011.262.593.264.240.7690.6569.843.463.810.45CB#16CB#170.280.5067126.30.0140.730.280.200.203.190.652.340.2790.3624.352.982.560.44CB#17CB#180.250.5062126.70.0140.710.530.180.383.061.172.340.5000.5006.002.982.990.35CB#19CB#180.050.5019126.30.0140.740.050.040.043.190.122.340.0510.1541.852.981.540.21CB#18CB#200.080.50137127.10.0140.760.080.060.502.971.482.340.6330.5857.022.983.170.72CB#20CB#210.200.5021127.80.0140.730.280.150.642.791.802.340.7690.6577.882.983.290.11CB#21CB#220.130.5025127.90.0140.630.410.080.732.772.012.340.8600.7138.562.983.350.12Page 1BASIN D1BASIN D2 21397-100YR.xlsFROM TO A s Ld Tc n CSUM AA*CSUM A*C I Qd QfQd/QfD/d D Vf VdTt=================================================================================================================================CB#22CB#230.100.5023128.00.0140.590.510.060.792.742.152.340.9200.7509.002.983.370.11CB#23CB#250.060.30117188.10.0140.840.570.050.842.712.275.340.4250.4578.223.022.920.67CB#24CB#250.099.8317126.30.0140.810.090.070.073.190.2310.370.0220.1051.2613.215.430.05CB#27CB#260.350.5089126.30.0140.70.350.250.253.190.782.340.3340.4004.802.982.700.55CB#26CB#250.750.5029126.90.0140.561.10.420.673.032.012.340.8610.7148.572.983.350.14CB#25CB#290.040.30150188.80.0140.250.040.011.612.584.175.340.7810.66411.953.023.350.75CB#28CB#290.150.5117126.30.0140.810.150.120.123.190.392.360.1640.2713.263.012.210.13CB#30CB#290.440.5027126.30.0140.360.440.160.163.190.512.340.2160.3133.762.982.370.19CB#29CB#320.060.30150189.60.0140.250.060.021.952.454.805.340.8980.73613.253.023.410.73CB#31CB#320.150.5117126.30.0140.810.150.120.123.190.392.360.1640.2713.263.012.210.13CB#32CB#340.060.301501810.30.0140.250.060.022.142.345.005.340.9370.76113.713.023.420.73CB#33CB#340.150.5117126.30.0140.810.150.120.123.190.392.360.1640.2713.263.012.210.13CB#D1CB#D217.100.20631820.00.0140.117.11.711.711.542.644.360.6050.56010.072.472.580.41CB#D2CB#D30.090.201621820.40.0140.117.190.011.721.522.624.360.6000.55710.032.472.581.05CB#D3CB#D40.060.20161821.50.0140.117.250.011.731.482.544.360.5840.5489.862.472.560.10CB#D4EX CB#10.010.221301821.60.0140.117.260.001.731.472.544.570.5550.5319.572.592.650.82Page 2BASIN D2BYPASS BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:21397-d1.bwp Surcharge condition at intermediate junctions Tailwater Elevation:89.62 feet Discharge Range:3.3 to 3.3 Step of 1. [cfs] Overflow Elevation:95.38 feet Weir:NONE Channel Width:1. feet PIPE NO. 1: 103 LF - 12"CP @ 0.50% OUTLET: 87.77 INLET: 88.28 INTYP: 5 JUNC NO. 1: OVERFLOW-EL: 91.68 BEND: 5 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.30 2.24 90.52 * 0.012 0.78 1.00 1.85 1.85 2.09 2.24 1.11 PIPE NO. 2: 53 LF - 12"CP @ 0.51% OUTLET: 88.28 INLET: 88.55 INTYP: 5 JUNC NO. 2: OVERFLOW-EL: 92.06 BEND: 19 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.03 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.30 2.54 91.09 * 0.012 0.78 1.00 2.24 2.24 2.36 2.54 1.14 PIPE NO. 3: 53 LF - 12"CP @ 0.49% OUTLET: 88.55 INLET: 88.81 INTYP: 5 JUNC NO. 3: OVERFLOW-EL: 92.51 BEND: 33 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.20 2.84 91.65 * 0.012 0.77 1.00 2.54 2.54 2.65 2.84 1.13 PIPE NO. 4: 61 LF - 12"CP @ 0.51% OUTLET: 88.81 INLET: 89.12 INTYP: 5 JUNC NO. 4: OVERFLOW-EL: 93.01 BEND: 28 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.23 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.20 3.23 92.35 * 0.012 0.77 1.00 2.84 2.84 2.95 3.23 1.22 PIPE NO. 5: 80 LF - 12"CP @ 0.50% OUTLET: 89.12 INLET: 89.52 INTYP: 5 JUNC NO. 5: OVERFLOW-EL: 93.62 BEND: 0 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.15 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 2.60 3.35 92.87 * 0.012 0.70 0.79 3.23 3.23 3.20 3.35 1.00 PIPE NO. 6: 51 LF - 12"CP @ 0.51% OUTLET: 89.52 INLET: 89.78 INTYP: 5 JUNC NO. 6: OVERFLOW-EL: 94.01 BEND: 0 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.17 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 2.27 3.38 93.16 * 0.012 0.65 0.70 3.35 3.35 3.27 3.38 0.92 SEE LEVEL 3 BACKWATER ANALYSIS BASIN D1 (MOLLASSES CREEK) BACKWATER ANALYSIS EX CB TO CB#1 CB#1 TO CB#2 CB#2 TO CB#4 CB#4 TO CB#5 CB#5 TO CB#7 CB#7 TO CB#9 PIPE NO. 7: 35 LF - 12"CP @ 0.51% OUTLET: 89.78 INLET: 89.96 INTYP: 5 JUNC NO. 7: OVERFLOW-EL: 94.27 BEND: 19 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.04 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.94 3.37 93.33 * 0.012 0.60 0.62 3.38 3.38 3.30 3.37 0.82 PIPE NO. 8: 52 LF - 12"CP @ 0.50% OUTLET: 89.96 INLET: 90.22 INTYP: 5 JUNC NO. 8: OVERFLOW-EL: 94.63 BEND: 13 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.26 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.86 3.32 93.54 * 0.012 0.59 0.61 3.37 3.37 3.23 3.32 0.83 PIPE NO. 9: 99 LF - 12"CP @ 0.49% OUTLET: 90.22 INLET: 90.71 INTYP: 5 JUNC NO. 9: OVERFLOW-EL: 95.38 BEND: 0 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.16 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.48 3.03 93.74 * 0.012 0.52 0.53 3.32 3.32 2.98 3.03 0.72 PIPE NO.10: 19 LF - 12"CP @ 0.53% OUTLET: 90.71 INLET: 90.81 INTYP: 5 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.27 3.01 93.82 * 0.012 0.48 0.48 3.03 3.03 2.95 3.01 0.68 CB#9 TO CB#11 CB#11 TO CB#12 CB#12 TO CB#14 CB#14 TO CB#15 BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:21397-D2-18.bwp Surcharge condition at intermediate junctions Tailwater Elevation:88.39 feet Discharge Range:5. to 5. Step of 1. [cfs] Overflow Elevation:94.23 feet Weir:NONE Channel Width:1. feet PIPE NO. 1: 14 LF - 18"CP @ 0.36% OUTLET: 87.80 INLET: 87.85 INTYP: 5 JUNC NO. 1: OVERFLOW-EL: 91.15 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.08 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 5.00 1.27 89.12 * 0.012 0.87 0.96 0.59 0.87 0.93 1.27 1.19 PIPE NO. 2: 150 LF - 18"CP @ 0.30% OUTLET: 87.85 INLET: 88.30 INTYP: 5 JUNC NO. 2: OVERFLOW-EL: 91.85 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.08 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 4.63 1.26 89.56 * 0.012 0.83 0.97 1.27 1.27 1.06 1.26 1.14 PIPE NO. 3: 150 LF - 18"CP @ 0.30% OUTLET: 88.30 INLET: 88.75 INTYP: 5 JUNC NO. 3: OVERFLOW-EL: 92.48 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.15 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 4.29 1.22 89.97 * 0.012 0.80 0.92 1.26 1.26 1.02 1.22 1.11 PIPE NO. 4: 150 LF - 18"CP @ 0.30% OUTLET: 88.75 INLET: 89.20 INTYP: 5 JUNC NO. 4: OVERFLOW-EL: 93.11 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.83 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.73 1.17 90.37 * 0.012 0.74 0.84 1.22 1.22 0.95 1.17 1.06 PIPE NO. 5: 117 LF - 18"CP @ 0.30% OUTLET: 89.20 INLET: 89.55 INTYP: 5 JUNC NO. 5: OVERFLOW-EL: 92.37 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.06 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 2.04 0.87 90.42 * 0.012 0.54 0.60 1.17 1.17 0.87 0.87 0.66 PIPE NO. 6: 23 LF - 12"CP @ 0.48% OUTLET: 89.55 INLET: 89.66 INTYP: 5 JUNC NO. 6: OVERFLOW-EL: 92.26 BEND: 72 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.07 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.92 0.99 90.65 * 0.012 0.60 0.63 0.87 0.87 0.80 0.99 0.89 SEE LEVEL 3 BACKWATER ANALYSIS BASIN D2 (WA-169) BACKWATER ANALYSIS OUTLE TO CB#36 CB#36 TO CB#33 CB#33 TO CB#30 CB#30 TO CB#26 CB#26 TO CB#23 CB#23 TO CB#22 PIPE NO. 7: 25 LF - 12"CP @ 0.52% OUTLET: 89.66 INLET: 89.79 INTYP: 5 JUNC NO. 7: OVERFLOW-EL: 92.23 BEND: 72 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.12 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.80 1.03 90.82 * 0.012 0.58 0.59 0.99 0.99 0.90 1.03 0.85 PIPE NO. 8: 21 LF - 12"CP @ 0.48% OUTLET: 89.79 INLET: 89.89 INTYP: 5 JUNC NO. 8: OVERFLOW-EL: 92.38 BEND: 90 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.22 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.60 1.09 90.98 * 0.012 0.54 0.56 1.03 1.03 0.97 1.09 0.81 PIPE NO. 9: 137 LF - 12"CP @ 0.50% OUTLET: 89.89 INLET: 90.57 INTYP: 5 JUNC NO. 9: OVERFLOW-EL: 95.41 BEND: 18 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.26 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.31 0.75 91.32 * 0.012 0.49 0.50 1.09 1.09 0.60 0.75 0.68 PIPE NO.10: 62 LF - 12"CP @ 0.65% OUTLET: 90.57 INLET: 90.97 INTYP: 5 JUNC NO.10: OVERFLOW-EL: 96.46 BEND: 10 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.80 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 1.04 0.60 91.57 * 0.012 0.43 0.40 0.75 0.75 0.43 ***** 0.60 PIPE NO.11: 67 LF - 12"CP @ 0.49% OUTLET: 90.97 INLET: 91.30 INTYP: 5 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 0.58 0.45 91.75 * 0.012 0.32 0.32 0.60 0.60 0.34 0.45 0.41 CB#21 TO CB#20 CB#20 TO CB#18 CB#18 TO CB#17 CB#17 TO CB#16 CB#22 TO CB#21 BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:21397-D2A.bwp Surcharge condition at intermediate junctions Tailwater Elevation:90.23 feet Discharge Range:2.01 to 2.01 Step of 1. [cfs] Overflow Elevation:93.86 feet Weir:NONE Channel Width:1. feet PIPE NO. 1: 29 LF - 12"CP @ 0.48% OUTLET: 89.20 INLET: 89.34 INTYP: 5 JUNC NO. 1: OVERFLOW-EL: 94.00 BEND: 51 DEG DIA/WIDTH: 2.0 Q-RATIO: 1.58 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 2.01 1.13 90.47 * 0.012 0.61 0.65 1.03 1.03 0.97 1.13 0.92 PIPE NO. 2: 89 LF - 12"CP @ 0.47% OUTLET: 89.34 INLET: 89.76 INTYP: 5 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 0.78 0.77 90.53 * 0.012 0.37 0.38 1.13 1.13 0.75 0.77 0.50 BASIN D2A (WA-169) BACKWATER ANALYSIS CB#25 TO CB#26 CB#26 TO CB#27 BACKWATER COMPUTER PROGRAM FOR PIPES Pipe data from file:21397-ebyp.bwp Using a broad-crested weir at intermediate junctions Individual CB's subject to surcharged condition should be simulated by raising the overflow elevation to an appropriate height above the rim elevation. Tailwater Elevation:91. feet Discharge Range:5. to 10. Step of 1. [cfs] Overflow Elevation:92.5 feet Weir:NONE Channel Width:6. feet PIPE NO. 1: 16 LF - 18"CP @ 0.19% OUTLET: 89.50 INLET: 89.53 INTYP: 5 JUNC NO. 1: OVERFLOW-EL: 93.31 BEND: 85 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.65 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 5.00 1.72 91.25 * 0.012 0.87 1.26 1.50 1.50 1.50 1.72 1.32 6.00 1.82 91.35 * 0.012 0.95 1.50 1.50 1.50 1.51 1.82 1.50 7.00 1.95 91.48 * 0.012 1.03 1.50 1.50 1.50 1.53 1.95 1.69 8.00 2.10 91.63 * 0.012 1.10 1.50 1.50 1.50 1.55 2.10 1.89 9.00 2.26 91.79 * 0.012 1.17 1.50 1.50 1.50 1.57 2.26 2.13 10.00 2.45 91.98 * 0.012 1.22 1.50 1.50 1.50 1.59 2.45 2.39 PIPE NO. 2: 162 LF - 18"CP @ 0.20% OUTLET: 89.53 INLET: 89.85 INTYP: 5 JUNC NO. 2: OVERFLOW-EL: 92.35 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.03 1.54 91.39 * 0.012 0.67 0.84 1.72 1.72 1.52 1.54 0.90 3.64 1.70 91.55 * 0.012 0.73 0.95 1.82 1.82 1.67 1.70 0.99 4.24 1.90 91.75 * 0.012 0.79 1.06 1.95 1.95 1.86 1.90 1.07 4.85 2.13 91.98 * 0.012 0.85 1.18 2.10 2.10 2.07 2.13 1.15 5.45 2.39 92.24 * 0.012 0.91 1.50 2.26 2.26 2.32 2.39 1.22 **************** OVERFLOW ENCOUNTERED AT 6.06 CFS DISCHARGE ***************** **************** OVERFLOW HEADWATERS ASSUME 6.4 FT. BROAD_WEIR **************** 6.06 2.59 92.44 * 0.012 0.91 1.50 2.45 2.45 2.51 2.59 ***** PIPE NO. 3: 63 LF - 18"CP @ 0.21% OUTLET: 89.85 INLET: 89.98 INTYP: 5 JUNC NO. 3: OVERFLOW-EL: 93.81 BEND: 90 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.00 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* 3.03 1.54 91.52 * 0.012 0.67 0.83 1.54 1.54 1.46 1.54 0.96 3.64 1.76 91.74 * 0.012 0.73 0.93 1.70 1.70 1.64 1.76 1.07 4.24 2.02 92.00 * 0.012 0.79 1.04 1.90 1.90 1.86 2.02 1.19 4.85 2.33 92.31 * 0.012 0.85 1.16 2.13 2.13 2.12 2.33 1.30 5.45 2.68 92.66 * 0.012 0.91 1.33 2.39 2.39 2.41 2.68 1.42 6.06 2.97 92.95 * 0.012 0.96 1.50 2.59 2.59 2.64 2.97 1.53 PIPE NO. 4: 25 LF - 18"CP @ 0.08% OUTLET: 89.98 INLET: 90.00 INTYP: 5 Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI ******************************************************************************* CROWN OF EX. 18" CMP CB#D4 TO CB#D3 CB#D3 TO CB#D2 CB#D2 TO CB#D1 CB#D1 TO INLET Q100 = 2.64 CFS, THERFORE OK 18-INCH BYPASS BACKWATER ANALYSIS 3.03 1.62 91.62 * 0.012 0.67 1.16 1.54 1.54 1.55 1.62 0.94 3.64 1.86 91.86 * 0.012 0.73 1.50 1.76 1.76 1.77 1.86 1.05 4.24 2.17 92.17 * 0.012 0.79 1.50 2.02 2.02 2.04 2.17 1.16 **************** OVERFLOW ENCOUNTERED AT 4.85 CFS DISCHARGE ***************** 4.85 2.53 92.53 * 0.012 0.85 1.50 2.33 2.33 2.36 2.53 1.26 5.45 2.94 92.94 * 0.012 0.91 1.50 2.68 2.68 2.72 2.94 1.37 6.06 3.30 93.30 * 0.012 0.96 1.50 2.97 2.97 3.02 3.30 1.47 CATCHMENT AREAS = Onsite Impervious C=0.90 Pervious C=0.25 Forest C=0.10 Catch Basin No.Impervious Area (SF) Pervious Area (SF) Forested Area (SF) Tributary Area (SF) Tributary Area (AC)Weighted C CB#34 0 3,720 0 3,720 0.09 0.25 CB#33 5,819 891 0 6,710 0.15 0.81 CB#32 0 2,741 0 2,741 0.06 0.25 CB#31 5,810 900 0 6,710 0.15 0.81 CB#30 3,208 15,929 0 19,137 0.44 0.36 CB#29 0 2,741 0 2,741 0.06 0.25 CB#28 5,810 900 0 6,710 0.15 0.81 CB#27 10,570 4,537 0 15,107 0.35 0.70 CB#26 15,586 16,984 0 32,570 0.75 0.56 CB#25 0 1,755 0 1,755 0.04 0.25 CB#24 3,402 529 0 3,931 0.09 0.81 CB#23 2,189 208 0 2,397 0.06 0.84 CB#22 2,208 2,055 0 4,263 0.10 0.59 CB#21 3,257 2,263 0 5,520 0.13 0.63 CB#20 6,361 2,184 0 8,545 0.20 0.73 CB#19 1,684 564 0 2,248 0.05 0.74 CB#18 2,738 729 0 3,467 0.08 0.76 CB#17 7,677 3,101 0 10,778 0.25 0.71 CB#16 8,883 3,194 0 12,077 0.28 0.73 CB#15 13,390 4,802 0 18,192 0.42 0.73 CB#14 2,875 445 0 3,320 0.08 0.81 CB#13 6,168 2,195 0 8,363 0.19 0.73 CB#12 1,940 432 0 2,372 0.05 0.78 CB#11 1,655 1,022 0 2,677 0.06 0.65 CB#10 4,682 1,646 0 6,328 0.15 0.73 CB#9 546 515 0 1,061 0.02 0.58 CB#8 7,143 9,805 0 16,948 0.39 0.52 CB#7 1,207 572 0 1,779 0.04 0.69 CB#6 9,476 5,433 0 14,909 0.34 0.66 CB#5 1,248 972 0 2,220 0.05 0.62 CB#4 981 525 0 1,506 0.03 0.67 CB#3 1,844 93 0 1,937 0.04 0.87 CB#2 1,284 0 0 1,284 0.03 0.90 CB#1 594 0 0 594 0.01 0.90 CB#D1 295 449 0 744 0.02 0.51 CB#D2 1,964 1,840 0 3,804 0.09 0.59 CB#D3 479 2,250 0 2,729 0.06 0.36 CB#D4 0 311 0 311 0.01 0.25 EX CB 3,340 776 0 4,116 0.09 0.78 EX CB#1 2,355 193 0 2,548 0.06 0.85 AVERAGE 0.65 ONLYGGEEGGEEGGEEGGEEGGEEG G EEGGEEGGEEGGEEGGEEGEGGEEGEG G EEGEIN COMPLIANCE WITH CITY OF RENTON STANDARDSTED QUADRANT HOMES(425) 455-290015900 SE EASTGATE WAY. SUITE 300BELLEVUE, WA 98008ELLIOT FARMS LUA:C:ELLIOT FARMS PR:ELLIOT FARMS”SCALE: 1"=30'1234567892021222324252627282930414021397-D121397-D2A21397-D2 SITE SITE Tab 6.0 21397.002-TIR.docx 6.0 SPECIAL REPORTS AND STUDIES This section will include other special reports and studies with the final engineering design approval process. The following special reports have been prepared for this project and are included in this section: 6.1 Geotechnical Report by Terra Associates, Inc., dated February 10, 2014 6.2 Wetland Report by Raedeke Associates, Inc. dated December 15, 2014 6.3 Cultural Resources Assessment prepared by SWCA Environmental Consultants dated August 4, 2016 6.4 Offsite Tree Protection report prepared by Greenforest Inc. dated February 22, 2021 Geotechnical Report by Terra Associates, Inc. dated February 25, 2015 6.1 Wetland Report by Raedeke Associates, Inc. dated December 15, 2014 6.2 Wetland & Aquatic Sciences Wildlife Ecology Landscape Architecture Associates, Inc. Raedeke December 15, 2014 Mr. Glen Mauer Pacific Properties, Inc. 14410 Bel-Red Road, Suite 200 Bellevue, WA 98007 RE: Elliot Farm – Wetland Delineation R.A.I. Project #2012-024-002 Dear Glen: At your request, we conducted a site investigation on June 26 and 27, 2012 to determine whether wetlands and streams were present on the Elliot Farm property. PROPERTY LOCATION The Elliot Farm property consists of an approximately 6-acre parcel, located along the south side of SR 169 (Renton-Maple Valley Highway), approximately 1,000 feet east of 140th Way SE, in the City of Renton, Washington. The property is identified as Tax Parcel No. 2223059004. This places the property in a portion of Section 22, Township 23 North, Range 5 East, W.M. Parcel maps retrieved on-line from King County (2012) iMAP depict the property boundaries. METHODOLOGY In order to identify potential wetland areas, we used the U. S. Army Corps of Engineers (COE) Wetlands Delineation Manual (Environmental Laboratory 1987). The COE, which requires use of the 1987 delineation manual, as amended, has federal regulatory jurisdiction of the dredging or filling of "Waters of the United States," including wetlands. As outlined in this methodology, the interaction of hydrophytic vegetation, hydric soil, and wetland hydrology must be present for an area to be classified as wetland. To be consistent with current regulations, field investigations were consistent with the Regional Supplement to the Corps of Engineers Delineation Manual: Western Mountains, Valleys, and Coast Region (COE 2010). BACKGROUND REVIEW Prior to conducting our site reconnaissance, we reviewed existing background maps and information from the U.S.D.A Natural Resources Conservation Service (NRCS 2014) Web Soil Survey and the U.S. Fish and Wildlife Service USFWS 2014) National Wetland Inventory (NWI). 9510 Stone Avenue N. Seattle, WA 98103 206-525-8122 www.raedeke.com Mr. Glen Mauer December 15, 2014 Page 2 The USDA NRCS (2014) Web Soil Survey shows the majority of the study area as an Newberg series soil. Newberg series soil is not considered a hydric soil (USDA Soil Conservation Service 1991 Federal Register 1995). Soil series boundaries or mapping units are mapped from aerial photographs with limited field verification. Thus, the location and extent of the boundaries between mapping units may be approximate for a given parcel of land within the survey area. The USFWS (2014) NWI does not depict wetlands on or within the immediate vicinity of the study area. Wetlands shown on the NWI are general in terms of locations and extent, as they are determined primarily from aerial photograph interpretation. Thus, the number and extent of existing wetlands located within the project area may differ from those marked on an NWI map. RESULTS During our site visit on June 26 and 27, 2012 we identified and delineated the boundary of a wetland located in the southwest portion of the Elliot Farm property (Figure 2). The wetland is a low-lying forested area in the southwest portion of the site. Vegetation in the wetland area is comprised of a red alder (Alnus rubra, FAC) canopy over a salmonberry (Rubus spectabilis, FAC) and Himalayn blackberry (Rubus armeniancus, FACU) shrub layer. Field horsetail (Equisetum arvense, FAC) and creeping buttercup (Ranunculus repens, FAC) are the dominant species identified in the herbaceous layer (Sample Plots 2 and 4, Appendix A). The majority of the species observed are rated facultative or wetter (Reed 1988), so the vegetation community would be considered hydrophytic, per the COE (2010) guidelines. Soils observed in the wetland are very dark grayish brown (10YR 3/2) silt loam over gray (10YR 5/1) and dark grayish brown (10YR 4/2) silt loams. The deeper soil profiles exhibited many redoximorphic features (mottles). Dark soils with mottles are positive indicators of hydric (wetland) soils per the COE (2010) guidelines. We encountered a water table at 18 inches below the ground surface during our June 2012 field investigations, and soils were saturated at a depth of 12 inches. These are considered positive indicators of wetland hydrology We did not identify any wetlands or critical areas in the remaining portion of the property. In general the property consists of previously cleared and graded areas that now support a vegetation community dominated by invasive plant species such as Himalayan blackberry and Scot’s Broom (Cytisus scoparius, UPL) and included small stands of red alder and black cottonwood (Populus balsamifera, FAC). Soils observed in the central portion of the site were bright (10YR 5/4) fine sandy loams. No hydrology was observed within 18 inches of the ground surface (Sample plots 1, 3, and 5; Appendix A). Mr. Glen Mauer December 15, 2014 Page 3 REGULATORY CONSIDERATIONS Wetlands and streams are protected by Section 404 of the Federal Clean Water Act and other state and local policies and ordinances, including City of Renton (2014b) municipal code. Regulatory considerations pertinent to wetlands identified within the study area are discussed below; this discussion, however, should not be considered comprehensive. Additional information may be obtained from agencies with jurisdictional responsibility for, or interest in, the site. A brief review of the U.S. Army Corps of Engineers and State of Washington regulations and of the City of Renton municipal code, relative to wetlands and streams, is presented below. Federal Clean Water Act (U.S. Army Corps of Engineers) In general, Federal law (Section 404 of the Clean Water Act) discourages the discharge of dredged or fill material into the nation’s waters, including most wetlands and streams, without a permit from the U.S. Army Corps of Engineers (COE). Certain wetlands, including many that are hydrologically isolated from “waters of the United States,” may not be regulated by the COE. The COE has the authority to make a final determination concerning whether an area (1) meets the definition of “waters of the United States” as defined by the federal government (Federal Register 1986:41251) and (2) is under federal jurisdiction. State of Washington The Washington Department of Ecology (WDOE) regulates all wetlands as ‘waters of the State” under Chapter 90.48 RCW (Water Pollution Control), including isolated wetlands determined to be non-jurisdictional by the COE. In addition, activities that will use, divert, obstruct, or change the natural flow or bed of any state waters must be approved by the Washington Department of Fish and Wildlife (WDFW), through its administration of the State Hydraulic Code (RCW 75.20.100-140). City of Renton The City of Renton (2014b) municipal code currently regulates wetlands and streams under Title IV, Chapter 3 – “Environmental Regulations and Overlay Districts.” Alterations of wetlands or streams and their buffers are generally prohibited, except as allowed under certain conditions specified in RMC Title IV. The City of Renton (2014) code specifies ratings, buffers, and allowed uses of wetlands and other sensitive areas that are under it’s jurisdiction. The wetland identified on the Elliot Farm property appears to meet the City of Renton criteria necessary to be considered a Category 2 system because it is not a Category 1 or 3 wetland. In order to be a Category 1 wetland the feature must contain habitat for listed species of wildlife or plants, contain 40% to 60% open water and two or more vegetation classes, or be greater than 10 acres in size with three or more vegetation classes. No Mr. Glen Mauer December 15, 2014 Page 4 species listed as endangered or threatened, or other priority species were observed during our field investigationa, nor are any mapped for the site by WDFW (2014). Category 3 wetlands are those that have been severely disturbed by human activities or are newly emerging with little vegetation diversity. The wetland on the Elliot Farm site does not meet either the Category 1 or Category 3 criteria and therefore meets the City of Renton’s criteria as a Category 2 wetland. Under the City of Renton code, Category 2 wetlands are provided with a standard buffer width of 50 feet. LIMITATIONS We have prepared this report for the exclusive use of the Pacific Properties, Inc. and their consultants. No other person or agency may rely upon the information, analysis, or conclusions contained herein without permission from Pacific Properties, Inc. The determination of ecological system classifications, functions, values, and boundaries is an inexact science, and different individuals and agencies may reach different conclusions. With regard to wetlands, the final determination of their boundaries for regulatory purposes is the responsibility of the various resource agencies that regulate development activities in wetlands. We cannot guarantee the outcome of such agency determinations. Therefore, the conclusions of this report should be reviewed by the appropriate regulatory agencies prior to any detailed site planning or construction activities. We warrant that the work performed conforms to standards generally accepted in our field, and that this work was prepared substantially in accordance with then-current technical guidelines and criteria. The conclusions of this report represent the results of our analysis of the information provided by the project proponents and their consultants, together with information gathered in the course of this study. No other warranty, expressed or implied, is made. Thank you for the opportunity to prepare this material for you. If you have any questions, please do not hesitate to call us at (206) 525-8122. Respectfully submitted, RAEDEKE ASSOCIATES, INC. Christopher W. Wright, Principal Soil and Wetland Scientist Mr. Glen Mauer December 15, 2014 Page 5 LITERATURE CITED Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual. Technical Report Y-87-1, US Army Engineers Waterways Experiment Station, Vicksburg, Mississippi. 100 pp. Federal Register. 1986. 40 CFR Parts 320 through 330: Regulatory programs of the Corps of Engineers; final rule. Vol. 51. No. 219. pp. 41206-41260, U.S. Government Printing Office, Washington, D.C. Federal Register. 1995. U.S. Department of Agriculture, Soil Conservation Service: Changes in Hydric Soils of the United States. Volume 59, No 133, July 13, 1994. Revised September 15, 1995. King County. 2012. iMAP GIS Interactive map center, King County, Washington. http://www.metrokc.gov/gis/iMAP_main.htm#. Accessed June 2012. Renton, City of. 2014. 4-3-050, Critical Areas Regulations, Title IV, Chapter 3 – Environmental Regulations and Overlay Districts. Renton Municipal Code online through Code Publishing Company, Seattle, WA. Current through Ordinance 5707, passed March 24, 2014. www.codepublishing.com/wa/renton/ Accessed November, 2014. U.S. Army Corps of Engineers. 2010. Regional supplement to the Corps of Engineers wetland delineation manual: western mountains, valleys, and coast region (Version 2.0). Wakeley, J.S., R.W. Lichvar, and C.V. Noble, eds. May 2010. ERDC/EL TR-10-3. U.S. Army Engineer Research and Development Center, Vicksburg, MS. U.S.D.A., Soil Conservation Service. 1991. Hydric soils of the United States: In cooperation with the National Technical Committee for Hydric Soils. U.S.D.A. Miscellaneous Publication Number 1491. U.S.D.A. Natural Resources Conservation Service. 2014. On-line Web Soil Survey. http://websoilsurvey.nrcs.usda.gov . Accessed November, 2014. U.S. Fish and Wildlife Service. 2014. National Wetland Inventory, Wetlands Online Mapper. http://wetlandsfws.er.usgs.gov/wtlnds/launch.html . Accessed November, 2014. FIGURES PROJECT LOCATION WETLAND CAT. II 50’ BUFFER FIGURE 2 WETLAND DELINEATION 2 3 SP-5 SP-4 SP-# SAMPLE PLOT LOCATIONS APPENDIX A FIELD DATA FORMS WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: Elliott Farm City/County: King County Sampling Date:June 27, 2012 Applicant/Owner: Murray-Franklyn State: WA Sampling Point: SP-1 Investigator(s): Chris Wright, Emmett Pritchard Section, Township, Range: S22, T23N, R5E, W.M. Landform (hillslope, terrace, etc.): Hillslope Local relief (concave, convex, none): Convex Slope (%): 2 Subregion (LRR): Northwest forests & coasts (LRR-A) Lat: 47.466510 Long: -122.151222 Datum: unknown Soil Map Unit Name: Newberg silt loam. NWI classification: none Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: Sample Plot 1 is located outside of the wetland, near wetland boundary flag WL-2A. VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 5m radius) % Cover Species? Status 1. Thuja plicata (western arborviate) 10 Y FAC 2. Apple spp. 5 NI NA 3. 4. 15 = Total Cover Sapling/Shrub Stratum (Plot size: 3m radius) 1. Rubus armeniacus (Himalayan blackberry) 70 Y FACU 2. Thuja plicata (western arborviate) 5 N FAC 3. Italian plum 5 NI NA 4. 5. 80 = Total Cover Herb Stratum (Plot size: 1m radius) 1. Equisetum arvense (field horsetail) 20 Y FAC 2. Ranunculus repens (creeping buttercup) 10 Y FAC 3. Phalaris arundinacea (reed canarygrass) 10 Y FACW 4. musci spp. 60 NI NA 5. 6. 7. 8. 9. 10. 11. 100 = Total Cover Woody Vine Stratum (Plot size: 3m radius) 1. 2. 0 = Total Cover % Bare Ground in Herb Stratum 10 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: 4 (A) Total Number of Dominant Species Across All Strata: 5 (B) Percent of Dominant Species That Are OBL, FACW, or FAC: 80 (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = Hydrophytic Vegetation Indicators: 1 - Rapid Test for Hydrophytic Vegetation 2 - Dominance Test is >50% 3 - Prevalence Index is ≤3.01 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 5 - Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: Various mosses were observed in the herb stratum. Musci species were not readily identifiable and therefore were not relied on as an wetland indicator for this survey. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: SP-1 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-10 10YR 4/2 Silt Loam 10-18+ 10YR 4/3 Silt Loam 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type: Depth (inches): Hydric Soil Present? Yes No Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Water Table Present? Yes No Depth (inches): Saturation Present? Yes No Depth (inches): (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No evidence of surface water was observed. Soils were not saturated and no water table was present to a depth of 18 inches. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: Elliott Farm City/County: King County Sampling Date:June 27, 2012 Applicant/Owner: Murray-Franklyn State: WA Sampling Point: SP-2 Investigator(s): Chris Wright, Emmett Pritchard Section, Township, Range: S22, T23N, R5E, W.M. Landform (hillslope, terrace, etc.): Depression Local relief (concave, convex, none): Concave Slope (%): 0 Subregion (LRR): Northwest forests & coasts (LRR-A) Lat: 47.466269 Long: -122.149914 Datum: unknown Soil Map Unit Name: Newberg silt loam. NWI classification: none Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: Sample Plot 2 is located in wetland, near wetland flag WL-9A. VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 5m radius) % Cover Species? Status 1. Alnus rubra (red alder) 30 Y FAC 2. 3. 4. 30 = Total Cover Sapling/Shrub Stratum (Plot size: 3m radius) 1. Rubus armeniacus (Himalayan blackberry) 20 Y FACU 2. Rubus spectabilis (salmon raspberry) 20 Y FAC 3. 4. 5. 40 = Total Cover Herb Stratum (Plot size: 1m radius) 1. Equisetum arvense (field horsetail) 40 Y FAC 2. Ranunculus repens (creeping buttercup) 20 Y FAC 3. Athyrium filix-femina (lady fern) 20 Y FAC 4. 5. 6. 7. 8. 9. 10. 11. 80 = Total Cover Woody Vine Stratum (Plot size: 3m radius) 1. 2. 0 = Total Cover % Bare Ground in Herb Stratum 0 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: 5 (A) Total Number of Dominant Species Across All Strata: 6 (B) Percent of Dominant Species That Are OBL, FACW, or FAC: 83 (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = Hydrophytic Vegetation Indicators: 1 - Rapid Test for Hydrophytic Vegetation 2 - Dominance Test is >50% 3 - Prevalence Index is ≤3.01 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 5 - Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: SP-2 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-6 10YR 3/2 Silt Loam 6-12 10YR 5/1 80 10YR 4/4 20 C M Silt Loam 12-18+ 10YR 4/2 60 10YR 4/4 40 C M Sandy Loam 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type: Depth (inches): Hydric Soil Present? Yes No Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Water Table Present? Yes No Depth (inches): 18 Saturation Present? Yes No Depth (inches): 12 (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: Soils become saturated at 12 inches and a water table is present at 18 inches. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: Elliott Farm City/County: King County Sampling Date:June 27, 2012 Applicant/Owner: Murray-Franklyn State: WA Sampling Point: SP-3 Investigator(s): Chris Wright, Emmett Pritchard Section, Township, Range: S22, T23N, R5E, W.M. Landform (hillslope, terrace, etc.): Hillslope Local relief (concave, convex, none): Convex Slope (%): 2 Subregion (LRR): Northwest forests & coasts (LRR-A) Lat: 47.465922 Long: -122.149948 Datum: unknown Soil Map Unit Name: Newberg silt loam. NWI classification: none Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: Sample Plot 3 is located outside of the wetland, near wetland boundary flag (WL-9A). VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 5m radius) % Cover Species? Status 1. 2. 3. 4. 0 = Total Cover Sapling/Shrub Stratum (Plot size: 3m radius) 1. Rubus armeniacus (Himalayan blackberry) 80 Y FACU 2. 3. 4. 5. 80 = Total Cover Herb Stratum (Plot size: 1m radius) 1. Equisetum arvense (field horsetail) 20 Y FAC 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 20 = Total Cover Woody Vine Stratum (Plot size: 3m radius) 1. 2. 0 = Total Cover % Bare Ground in Herb Stratum 0 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: 1 (A) Total Number of Dominant Species Across All Strata: 2 (B) Percent of Dominant Species That Are OBL, FACW, or FAC: 50 (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species 20 x 3 = 60 FACU species 80 x 4 = 320 UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = 3.8 Hydrophytic Vegetation Indicators: 1 - Rapid Test for Hydrophytic Vegetation 2 - Dominance Test is >50% 3 - Prevalence Index is ≤3.01 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 5 - Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: SP-3 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-9 10YR 3/2 Silt Loam 9-13 10YR 4/2 95 10YR 4/3 5 C M Silt Loam 13-18+ 10YR 5/3 Sandy Loam 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type: Depth (inches): Hydric Soil Present? Yes No Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Water Table Present? Yes No Depth (inches): Saturation Present? Yes No Depth (inches): (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No evidence of inundation was observed. Soil saturated was not observed and no aparent water table was present within the upper 18 inches of the soil profile. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: Elliott Farm City/County: King County Sampling Date:June 27, 2012 Applicant/Owner: Murray-Franklyn State: WA Sampling Point: SP-4 Investigator(s): Chris Wright, Emmett Pritchard Section, Township, Range: S22, T23N, R5E, W.M. Landform (hillslope, terrace, etc.): Depression Local relief (concave, convex, none): Concave Slope (%): 0 Subregion (LRR): Northwest forests & coasts (LRR-A) Lat: 47.466269 Long: -122.149914 Datum: unknown Soil Map Unit Name: Newberg silt loam. NWI classification: none Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: Sample Plot 4 is located in a paulstrine, forested community near wetland boundary flag (WL-7A). VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 5m radius) % Cover Species? Status 1. Alnus rubra (red alder) 80 Y FAC 2. Thuja plicata (western arborviate) 20 Y FAC 3. 4. 100 = Total Cover Sapling/Shrub Stratum (Plot size: 3m radius) 1. Rubus spectabilis (salmon raspberry) 10 Y FAC 2. Ilex aquifolium (English holly) 5 N FACU 3. 4. 5. 15 = Total Cover Herb Stratum (Plot size: 1m radius) 1. Scripus microcarpus (bulrush) 30 Y OBL 2. Ranunculus repens (creeping buttercup) 30 Y FAC 3. Lysichiton americanus (skunk cabbage) 10 N OBL 4. Athyrium filix-femina (lady fern) 10 N FAC 5. Veronica beccabunga (European speedwell) 10 N OBL 6. Tolmiea menziesii (piggy-back plant) 5 N FAC 7. Urtica dioica (stinging nettle) 5 N FAC 8. Glyceria elata (tall mana grass) 1 N FACW 9. 10. 11. 101 = Total Cover Woody Vine Stratum (Plot size: 3m radius) 1. 2. 0 = Total Cover % Bare Ground in Herb Stratum 0 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: 5 (A) Total Number of Dominant Species Across All Strata: 5 (B) Percent of Dominant Species That Are OBL, FACW, or FAC: 100 (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = Hydrophytic Vegetation Indicators: 1 - Rapid Test for Hydrophytic Vegetation 2 - Dominance Test is >50% 3 - Prevalence Index is ≤3.01 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 5 - Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: SP-4 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-18+ 10YR 3/1 Mucky Peat 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type: Depth (inches): Hydric Soil Present? Yes No Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): 3" Water Table Present? Yes No Depth (inches): 0 Saturation Present? Yes No Depth (inches): 0 (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: Soils are saturated to the surface, and several 100 square-foot pools approximateley 3 inches deep are located adjacent to the sample plot. A 24 inch wide stream channel is flowing to the west. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: Elliott Farm City/County: King County Sampling Date:June 27, 2012 Applicant/Owner: Murray-Franklyn State: WA Sampling Point: SP-5 Investigator(s): Chris Wright, Emmett Pritchard Section, Township, Range: S22, T23N, R5E, W.M. Landform (hillslope, terrace, etc.): Hillslope Local relief (concave, convex, none): Convex Slope (%): 2 Subregion (LRR): Northwest forests & coasts (LRR-A) Lat: 47.466510 Long: -122.151222 Datum: unknown Soil Map Unit Name: Newberg silt loam. NWI classification: none Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: Sample Plot 5 is located in a stand of alder and balsam poplar, near the central portion of the site. VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 5m radius) % Cover Species? Status 1. Alnus rubra (red alder) 50 Y FAC 2. Populus balsamifera (balsam poplar) 25 Y FAC 3. 4. 75 = Total Cover Sapling/Shrub Stratum (Plot size: 3m radius) 1. Rubus armeniacus (Himalayan blackberry) 75 Y FACU 2. 3. 4. 5. 75 = Total Cover Herb Stratum (Plot size: 1m radius) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 0 = Total Cover Woody Vine Stratum (Plot size: 3m radius) 1. 2. 0 = Total Cover % Bare Ground in Herb Stratum 0 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: 2 (A) Total Number of Dominant Species Across All Strata: 3 (B) Percent of Dominant Species That Are OBL, FACW, or FAC: 75 (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species 75 x 3 = 225 FACU species 75 x 4 = 300 UPL species x 5 = Column Totals: 150 (A) 550 (B) Prevalence Index = B/A = 3.7 Hydrophytic Vegetation Indicators: 1 - Rapid Test for Hydrophytic Vegetation 2 - Dominance Test is >50% 3 - Prevalence Index is ≤3.01 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 5 - Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: SP-5 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-12+ 10YR 5/4 F.S.L 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type: Depth (inches): Hydric Soil Present? Yes No Remarks: Soils at the sample plot location are extremely rocky/gravely. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Water Table Present? Yes No Depth (inches): Saturation Present? Yes No Depth (inches): (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No evidence of inundation was observed. Soils were not saturated and no water table was detected within the upper 12 inches of the soil profile. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 CULTURAL RESOURCES ASSESSMENT 6.3 Tel: 206-781-1909 Fax: 206-781-0154 Email: mparvey@swca.com www.swca.com August 4, 2016 Todd Levitt Murray Franklyn A Family of Companies 14410 Bel-Red Road Bellevue, WA 98007 RE: Preliminary Results of the Cultural Resources Assessment for the Elliott Farm Property Dear Mr. Levitt, Per your request, the following provides a brief summary of the results of the cultural resources assessment for the Elliott Farm property, the technical report is in progress. No significant cultural resources were identified during the course of this investigation. Prior to field investigations, SWCA reviewed archaeological survey and site inventory records using the Washington Information System for Architectural and Archaeological Records Data (WISAARD) maintained by the Washington State Department of Archaeology and Historic Preservation (DAHP). This research identified no known pre-contact sites in the project parcel. The c. 1906 Elliott Farm complex, including the farm house and outbuildings, had been recorded on a King County Historic Sites Survey Inventory Form in 1978 (Wissel 1979) and nominated as a King County Landmark in 1990 (Younger and Quackenbush 1990). After the parcel was annexed to the City of Renton in 2006, the structures associated with the farm were demolished. Present day aerial photos show the remains of foundations from outbuildings on the property. Fieldwork was conducted on July 29-30, 2016 and included pedestrian survey of the project area and excavation of 26 shovel probes (SPs). SPs measured 40 cm (15 inches) in diameter and were excavated to roughly one-meter (3-feet) below ground surface. Spoils from each were screened through ¼-inch mesh. Sediments in shovel probes were highly variable due to historical and modern disturbance. Disturbed areas include fill deposits of variable thickness, especially in the vicinity of modern utilities and historical development. Natural sediments consist of silt, sand, and gravel alluvium. No significant cultural materials were encountered in any of the SPs. Foundation slabs from several of the former outbuildings were documented, and a Washington State Site Inventory Form will be completed and submitted to the DAHP. No demolition debris or isolated artifacts associated with the former Elliott Farm were identified during survey of the parcel. The Elliott Farm archaeological site fails to meet significance criteria and is not recommended eligible for listing on the National Register of Historic Places. No significant cultural resources were observed during this assessment. SWCA does not recommend any further cultural resources investigation for this project based on the current project area provided by Murray Franklyn. In the unlikely event that ground- disturbing construction activities result in the inadvertent discovery of buried archaeological materials, work should be temporarily suspended at that location and a professional archaeologist should document and assess the discovery. DAHP should be contacted for any issues involving Native American SWCA Environmental Consultants 2 INSERT DATE cultural resources. In the unlikely event that human remains, either in the form of burials, isolated bones or teeth, or other mortuary items are discovered during construction, work in the area of discovery should be stopped immediately and the discovery area should be secured. Local law enforcement, DAHP and affected Tribes should be contacted immediately. No additional excavation should be undertaken until a process has been agreed upon by these parties. No exposed human remains should be left unattended. If you have any questions or comments regarding the results of the field investigation, please do not hesitate to contact me. Sincerely Michele Parvey, M.A. RPA Project Archaeologist References Cited: Younger, Erin and Tom Quackenbush 1990 King County Landmark Registration Form. Document on file, Department of Archaeology and Historic Preservation, Olympia, WA. Wissel, Jayne 1978 King County Historic Sites Survey Inventory Form. Document on file, Department of Archaeology and Historic Preservation, Olympia, WA. Wetpool Sizing WorksheetOff-site Tree Protection report prepared by Greenforest Inc. dated February 22,2021 6.4 Greenforest Incorporated C o n s u l t i n g A r b o r i s t 4547 South Lucile Street, Seattle, WA 98118 Tel. 206-723-0656 TO: Mark Sumrok Barghausen Consulting Engineers, Inc. 300 Deschutes Way SW, Suite 215 Tumwater WA 98501 REFERENCE: Offsite Tree Protection Elliott Farm, BCE #21397 DATE: February 22, 2021 PREPARED BY: Favero Greenforest, ISA Certified Arborist # PN -0143A ISA Tree Risk Assessment Qualified ASCA Registered Consulting Arborist® #379 Proposed site improvements at the referenced project include construction of a wall at the rear of lots 26-33, near the shared property line. The soil cut is necessary to create a flat pad for home construction on these lots. I visited the site last week to assess the potential impacts of the excavation to offsite trees. I measured the DBH and driplines, and I identified 5 offsite trees. I calculated limits of disturbance (LOD) for each tree. They are listed below as radii in feet from the trunk. They are determined using rootplate1 and trunk diameter,2,3,4 and ISA Best Management Practices.5 1 Coder, Kim D. 2005. Tree Biomechanics Series. University of Georgia School of Forest Resources. 2 Smiley, E. Thomas, Ph. D. Assessing the Failure Potential of Tree Roots, Shade Tree Technical Report. Bartlett Tree Research Laboratories. 3 Fite, Kelby and E. Thomas Smiley. 2009. Managing Trees During construction; Part Two. Arborist News. ISA. 4 Andrew R. Benson, Andrew Koeser, Justin Morgenroth. Responses Of Mature Roadside Trees To Root Severance Treatments. 2019. Journal of Urban Forestry & Urban Greening. 5 Companion publication to the ANSI A300 Series, Part 5: Managing Trees During Construction. 2008. ISA. Mark Sumrok, Barghausen Consulting Engineers, Inc. RE: Offsite Tree Protection, Elliott Farm, BCE #21397 February 22, 2021 Page 2 of 3 Greenforest Registered Consulting Arborist These are the minimum distances from the center of the tree for a soil cut deeper than 9” below existing grade. These distances also assume a single linear cut past the tree, and on only one side of the tree, and that no branches are harmed or will need to be pruned to accommodate the excavation. The exhibit below identifies 5 trees on the abutting parcel with driplines and limits of disturbance shown. (Tree 2 is on the project site and will be removed.) Tree attributes are included in a separate table. The LODs of all 5 offsite trees are south of the shared boundary, and none of the trees will be negatively impacted by the proposed cut along the property line. Protection along the property line is adequate to preserve the stability and existing conditions of these trees. Mark Sumrok, Barghausen Consulting Engineers, Inc. RE: Offsite Tree Protection, Elliott Farm, BCE #21397 February 22, 2021 Page 3 of 3 Greenforest Registered Consulting Arborist Tree Attributes Regulated Category Tree No. DBH Species Dripline (R') Condition Comments on Condition LOD (R') Significant 1 6" Bitter cherry 12' Fair Previously topped 6' Significant 2 (5) 6" Bitter cherry 12' Fair Multiple leaders 7' Dangerous 3 36”, 38" Western red-cedar 21' Very Poor Double leader, previously topped, extensive decay at wound, recent failure of scaffold branches 26' Landmark 4 34" Garry oak 40' Good 22' Landmark 5 56" Bigleaf maple 45' Good Trunk decay, old age 28' Significant 6 (4) 6-9" Bigleaf maple 18' Good Stumpsprout 8' Tab 7.0 21397.002-TIR 7.0 OTHER PERMITS Applicable permits from the city of Renton to construct the project improvements is obtained by the approval of the civil plans. The following is a list of permits that will be in addition to the civil permits from the city of Renton: 7.1 Pre-Annexation Development Agreement 7.2 Approved Fire Hydrant Location 7.3 Postmaster / Mailbox Locations Approval 7.4 Construction Stormwater General Permit (Department of Ecology) 7.5 Building permit for on-site retaining walls 7.6 WSDOT approval for SR-169 Improvements Postmaster Approval dated December 11, 2020 7.37.2 Fire Hydrant Location Approval ELLIOTT FARMS SCALE: 1"=30' 3/12/21 By: cthomas Date: 03/15/2021 FIRE DEPARTMENT For Construction Subject to Corrections Noted in Red APPROVED Postmaster Approval dated December 11, 2020 7.3 Postmaster Approval dated December 11, 2020 7.37.4 Construction Stormwater General Permit (Department of Ecology) Tab 8.0 21397.002-TIR.docx 8.0 CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN (CSWPP) ANALYSIS AND DESIGN A. Erosion and Sediment Control (ESC) Plan Analysis and Design The erosion and sediment control plans were prepared in accordance with the 2009 King County Surface Water Design Manual, and standard industry practices throughout the construction process to limit the amount of sediment traveling into the downstream systems. The BMPs being proposed include a stabilized rocked construction entrance, silt fence where needed, NGPE fencing, straw mulch for the areas that reach final grade in the lot areas, V-ditches with rock check dams, temporary sediment ponds, and hydro seeding. Clearing limits are shown on the final engineering plans. Two temporary sediment ponds have been placed at the downstream drainage points of the project. A sediment pond (sediment pond #1) is located at the northwest corner and one a sediment trap is located at the northeast corner (sediment trap #2). Sediment pond #1 has a basin area of 3.29 acres. Sediment trap #1 has a basin area of 1.43 acres. The WWHM program was used to size the sediment pond and sediment trap. The full basin area was assumed to be landscape (grass) area. The 2-year predicted flow rate was used to size the sediment trap and the 10-year flow rate was used to size the sediment pond. Sediment Trap #1 (NE CORNER): S.A. = 2 x Q2/0.00096 = 2080 square feet per cfs of inflow Q2 = 0.134 (See WWHM calculations) S.A. = 0.134 x 2080 = 279 sf S.A. Required = 279 sf S.A. Provided = 1,015 sf Sediment Pond #1 (NW corner): S.A. = 2 x Q10/0.00096 = 2080 square feet per cfs of inflow Q10 = 0.745 (See WWHM calculations) S.A. = 0.745 x 2080 = 396 sf S.A. Required = 1,550 sf S.A. Provided = 1,630 sf · Find Size of Dewatering Orifice: A0 = SA(2H)0.5 SA = 1,550 sf 0.6 x 3,600Tg0.5 H = 3.5 feet T = 24 hours G = 32.2 ft/s2 A0 = 1,550(2 x 3.5)0.5 0.6 x 3,600 x 24 x 32.20.5 A0 = 0.0139 sf 21397.002-TIR.docx · Find Orifice Diameter: D = 24 x p 0A =13.54 x 0A 13.54 x √0.0139 D = 1.60 inches B. Stormwater Pollution Prevention and Spill (SWPPS) Plan Design A Stormwater Pollution Prevention Plan (SWPPP) will be prepared with the final engineering plan approval process. The SWPPP report will be prepared following the Department of Ecology (DOE) format and will be kept on-site during all construction activities. The SWPPP report will include a narrative discussion of construction BMP’s that will be implemented during construction, based on the 13 required elements as defined by DOE. The SWPPP report will also outline inspection, monitoring, and reporting requirements to meet the requirements of the NPDES permit. A Stormwater Pollution Prevention and Spill (SWPPS) Site Plan is also included in the construction plans. This plan provided suggested locations for: · equipment parking/maintenance areas · chemical storage areas with secondary containment · construction materials and construction waste storage areas · truck wheel washout areas This plan also provides general locations of erosion control such as silt fencing, temporary sediment traps, construction entrances, and clearing limits. The site is generally underlain by alluvial soils. A seasonally high groundwater table will be present during the wet winter and early spring months. Potential Spill Sources or Releases Potential spill sources during construction will include materials and equipment brought on- site. Potential spill sources include; fueling, lubricating oil, hydraulic oil, backhoes, bulldozers, water trucks, support trucks, lighting units, pumps, and generators. Equipment staging and maintenance areas for fueling, hazardous materials, and hazardous waste materials have been designated on the SWPPS. Construction debris will be present during demolition of the existing on-site buildings. No fuel tanks, gasoline, oils and hydraulic fuels will be stored on-site. Control Pollutants Pollutants other than sediment will be controlled as part of the implemented SWPPS plan. Maintenance and repair of heavy equipment and vehicles that may result in discharge or spillage of pollutants to the ground or surface water runoff will be conducted using spill prevention measures. Contaminated surfaces will be cleaned immediately following any discharge or spill incident. Spills will be reported within 24 hours. Emergency repairs may be performed on-site using temporary plastic placed beneath and, if raining, over the vehicle. 21397.002-TIR.docx Concrete truck chutes and pumps shall be washed out only into formed areas awaiting installation of concrete or asphalt. Unused concrete remaining in the truck and pump shall be returned to the originating batch plant for recycling. Hand tools including, but not limited to, screeds, shovels, rakes and trowels shall be washed off only into formed areas awaiting installation of concrete or asphalt. When no formed areas are available, washwater and leftover product shall be contained in a lined container or in a sump designed to receive the materials. Contained concrete shall be disposed of in manner that does not violate groundwater or surface water quality standards. Recommended BMP’s include Concrete Handling (BMP C151) Spill Prevention and Containment The following is a list of BMP’s that will be used for the project. · Store and maintain equipment in a designated area. · Reduce the amount of hazardous materials and waste by substituting non-hazardous or less hazardous materials. · Use secondary containment (drain pan) to catch spills when removing or changing fluids. · Use proper equipment (pumps, funnels) to transfer fluids · Keep spill kits readily accessible. · Check incoming vehicles for leaking oil and fluids. · Transfer used fluids and oil filters to waste or recycling drums. · Inspect equipment immediately, if necessary. · Implement a preventative maintenance schedule for equipment and vehicles. · Perform fueling in designated fueling area. · Do not “top-off” tanks · Use secondary containment (drain pan) to catch spills. · Keep spill kits readily accessible. · Inspect fueling areas routinely for leaks and spills. · Monitor pollution prevention BMP’s and maintain records/reports of all inspections using the worksheets at the end of this section. Spill Response Response in the first 15 minutes is critical to minimize the impacts to human health and the environment and to minimize property damage and cleanup costs. The contractor will respond immediately to spills and regulated materials. Spill response equipment shall be stored in spill response kits located in a clearly marked and accessible area. The standard approach toward spill response will be as follows: · Stop operations. · Stop the source of the spill. · Use appropriate materials to absorb, berm, or cover the area to prevent further contamination. 21397.002-TIR.docx · Notify the construction manager. · Determine the method of clean up required. All methods shall comply with the state or local requirements to spill response. · Contact a cleanup response firm if necessary. Contact Personnel The designated personnel responsible for managing, implementing and maintaining this SWPPS plan include: Client: Quadrant Homes CECL: - TBD The contractor – TBD A SWPPP report has also been prepared following the Department of Ecology (Ecology) format and will be kept on-site during all construction activities. The SWPPP report includes a narrative discussion of construction BMP’s that will be implemented during construction, based on the 12 required elements as defined by Ecology. The SWPPP report also outlines inspection, monitoring, and reporting requirements to meet the requirements of the NPDES permit. WWHM2012 PROJECT REPORT SEDIMENT POND CALULATIONS 21397-Tesc Flows 2/26/2021 9:05:59 AM Page 2 General Model Information Project Name:21397-Tesc Flows Site Name:Elliot Farms Site Address: City: Report Date:2/26/2021 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2018/03/02 Version:4.2.14 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Low Flow Threshold for POC2:50 Percent of the 2 Year High Flow Threshold for POC2:50 Year 21397-Tesc Flows 2/26/2021 9:05:59 AM Page 3 Landuse Basin Data Predeveloped Land Use 21397-Tesc Flows 2/26/2021 9:05:59 AM Page 4 Mitigated Land Use West sediment pond Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Mod 3.29 Pervious Total 3.29 Impervious Land Use acre Impervious Total 0 Basin Total 3.29 Element Flows To: Surface Interflow Groundwater 21397-Tesc Flows 2/26/2021 9:05:59 AM Page 5 East sediment trap Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Mod 1.43 Pervious Total 1.43 Impervious Land Use acre Impervious Total 0 Basin Total 1.43 Element Flows To: Surface Interflow Groundwater 21397-Tesc Flows 2/26/2021 9:05:59 AM Page 7 Mitigated Routing SEDIMENT POND #1 SEDIMENT TRAP #1 21397-Tesc Flows 2/26/2021 9:06:15 AM Page 12 Mitigated Schematic 21397-Tesc Flows 12/4/2020 2:36:54 PM Page 20 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2020; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com Tab 9.0 21397.002-TIR 9.0 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT The city of Renton Bond Quantity Worksheet is included within this section. Facilities Summary and Declaration of Covenant are not required for this project. Planning Division |1055 South Grady Way – 6 th Floor | Renton, WA 98057 (425) 430-7200 • • Section I: Project Information • • • Section II: Bond Quantities Worksheets • •Section II.a EROSION CONTROL (Stabilization/Erosion Sediment Control (ESC)) •Section II.b TRANSPORTATION (Street and Site Improvements) •Section II.c DRAINAGE (Drainage and Stormwater Facilities): •Section II.d WATER - ONLY APPLICABLE IF WATER SERVICE IS PROVIDED BY CITY OF RENTON •Section II.e SANITARY SEWER - ONLY APPLICABLE IF SEWER SERVICE IS PROVIDED BY CITY OF RENTON • • • • • • Section III. Bond Worksheet • This section calculates the required Permit Bond for construction permit issuance as well as the required Maintenance Bond for project close-out submittals to release the permit bond on a project. All unit prices include labor, equipment, materials, overhead and profit. Complete the 'Quantity' columns for each of the appropriate section(s). Include existing Right-of-Way (ROW), Future Public Improvements and Private Improvements. The 'Quantity Remaining' column is only to be used when a project is under construction. The City allows one (1) bond reduction during the life of the project with the exception of the maintenance period reduction. Excel will auto-calculate and auto-populate the relevant fields and subtotals throughout the document. Only the 'Quantity' columns should need completing. Additional items not included in the lists can be added under the "write-in" sections. Provide a complete description, cost estimate and unit of measure for each write-in item. Note: Private improvements, with the exception of stormwater facilities, are not included in the bond amount calculation, but must be entered on the form. Stormwater facilities (public and private) are required to be included in the bond amount. BOND QUANTITY WORKSHEET INSTRUCTIONS This worksheet is intended to be a "working" copy of the bond quantity worksheet, which will be used throughout all phases of the project, from initial submittal to project close-out approval. Submit this workbook, in its entirety, as follows: The following forms are to be completed by the engineer/developer/applicant as applicable to the project: The Bond Worksheet form will auto-calculate and auto-populate from the information provided in Section I and Section II. This section includes all pertinent information for the project Section II contains a separate spreadsheet TAB for each of the following specialties: (1) electronic copy (.xlsx format) and (1) hard copy of the entire workbook for civil construction permit submittal. Hard copies are to be included as part of the Technical Information Report (TIR). (1) electronic copy (.xlsx format) and (1) hard copy of the entire workbook for final close-out submittal. This section must be completed in its entirety Information from this section auto-populates to all other relevant areas of the workbook Page 1 of 14 Ref 8-H Bond Quantity Worksheet INSTRUCTIONS Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 Planning Division |1055 South Grady Way – 6 th Floor | Renton, WA 98057 (425) 430-7200 Date Prepared: Name: PE Registration No: Firm Name: Firm Address: Phone No. Email Address: Project Name: Project Owner: CED Plan # (LUA):Phone: CED Permit # (U):Address: Site Address: Street Intersection:Addt'l Project Owner: Parcel #(s):Phone: Address: Clearing and grading greater than or equal to 5,000 board feet of timber? Yes/No:NO Water Service Provided by: If Yes, Provide Forest Practice Permit #:Sewer Service Provided by: SITE IMPROVEMENT BOND QUANTITY WORKSHEET PROJECT INFORMATION CEDAR RIVER WATER AND SEWER CEDAR RIVER WATER AND SEWER 1 Select the current project status/phase from the following options: For Approval - Preliminary Data Enclosed, pending approval from the City; For Construction - Estimated Data Enclosed, Plans have been approved for contruction by the City; Project Closeout - Final Costs and Quantities Enclosed for Project Close-out Submittal --- Engineer Stamp Required (all cost estimates must have original wet stamp and signature) Clearing and Grading Utility Providers N/A Project Location and Description Project Owner Information Elliott Farms Bellevue, WA 98008 222305-9004 Tripointe Homes 15-000242 425-452-6546 4/20/2021 Prepared by: FOR APPROVALProject Phase 1 Btalkington@barghausen.com Barry Talkington 41423 Barghausen Consulting Engineers Inc. 18215 72nd Ave S Kent, WA 98032 425-251-6222 14207 Maple Valley RD Renton, WA 98058 15900 SE Eastgate Way, Suite 300 MWSH Renton LLCRenton Maple Valley Road C20-005641 3425 Boone Road SEAbbreviated Legal Description: Parcel A of King County Boundary Line Adjustment No. L95L0113 Recording No. 9510179023 Salem, OR 97317 Page 2 of 14 Ref 8-H Bond Quantity Worksheet SECTION I PROJECT INFORMATION Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 04/21/21 CED Permit #:C20-005641 Unit Reference #Price Unit Quantity Cost Backfill & compaction-embankment ESC-1 6.50$ CY Check dams, 4" minus rock ESC-2 SWDM 5.4.6.3 80.00$ Each 17 1,360.00 Catch Basin Protection ESC-3 35.50$ Each 38 1,349.00 Crushed surfacing 1 1/4" minus ESC-4 WSDOT 9-03.9(3)95.00$ CY 40 3,800.00 Ditching ESC-5 9.00$ CY Excavation-bulk ESC-6 2.00$ CY 205 410.00 Fence, silt ESC-7 SWDM 5.4.3.1 1.50$ LF 460 690.00 Fence, Temporary (NGPE)ESC-8 1.50$ LF 620 930.00 Geotextile Fabric ESC-9 2.50$ SY Hay Bale Silt Trap ESC-10 0.50$ Each Hydroseeding ESC-11 SWDM 5.4.2.4 0.80$ SY 17500 14,000.00 Interceptor Swale / Dike ESC-12 1.00$ LF 1960 1,960.00 Jute Mesh ESC-13 SWDM 5.4.2.2 3.50$ SY Level Spreader ESC-14 1.75$ LF Mulch, by hand, straw, 3" deep ESC-15 SWDM 5.4.2.1 2.50$ SY Mulch, by machine, straw, 2" deep ESC-16 SWDM 5.4.2.1 2.00$ SY 17500 35,000.00 Piping, temporary, CPP, 6"ESC-17 12.00$ LF Piping, temporary, CPP, 8"ESC-18 14.00$ LF Piping, temporary, CPP, 12"ESC-19 18.00$ LF Plastic covering, 6mm thick, sandbagged ESC-20 SWDM 5.4.2.3 4.00$ SY Rip Rap, machine placed; slopes ESC-21 WSDOT 9-13.1(2)45.00$ CY Rock Construction Entrance, 50'x15'x1'ESC-22 SWDM 5.4.4.1 1,800.00$ Each Rock Construction Entrance, 100'x15'x1'ESC-23 SWDM 5.4.4.1 3,200.00$ Each 2 6,400.00 Sediment pond riser assembly ESC-24 SWDM 5.4.5.2 2,200.00$ Each 1 2,200.00 Sediment trap, 5' high berm ESC-25 SWDM 5.4.5.1 19.00$ LF 300 5,700.00 Sed. trap, 5' high, riprapped spillway berm section ESC-26 SWDM 5.4.5.1 70.00$ LF 15 1,050.00 Seeding, by hand ESC-27 SWDM 5.4.2.4 1.00$ SY Sodding, 1" deep, level ground ESC-28 SWDM 5.4.2.5 8.00$ SY Sodding, 1" deep, sloped ground ESC-29 SWDM 5.4.2.5 10.00$ SY TESC Supervisor ESC-30 110.00$ HR 80 8,800.00 Water truck, dust control ESC-31 SWDM 5.4.7 140.00$ HR 120 16,800.00 Unit Reference #Price Unit Quantity Cost EROSION/SEDIMENT SUBTOTAL:100,449.00 SALES TAX @ 10%10,044.90 EROSION/SEDIMENT TOTAL:110,493.90 (A) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR EROSION & SEDIMENT CONTROL Description No. (A) WRITE-IN-ITEMS Page 3 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.a EROSION_CONTROL Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost GENERAL ITEMS Backfill & Compaction- embankment GI-1 6.00$ CY 1000 6,000.00 1663 9,978.00 17337 104,022.00 Backfill & Compaction- trench GI-2 9.00$ CY Clear/Remove Brush, by hand (SY)GI-3 1.00$ SY Bollards - fixed GI-4 240.74$ Each Bollards - removable GI-5 452.34$ Each Clearing/Grubbing/Tree Removal GI-6 10,000.00$ Acre 0.29 2,900.00 0.8 8,000.00 4.45 44,500.00 Excavation - bulk GI-7 2.00$ CY 700 1,400.00 8300 16,600.00 Excavation - Trench GI-8 5.00$ CY Fencing, cedar, 6' high GI-9 20.00$ LF Fencing, chain link, 4'GI-10 38.31$ LF Fencing, chain link, vinyl coated, 6' high GI-11 20.00$ LF Fencing, chain link, gate, vinyl coated, 20' GI-12 1,400.00$ Each Fill & compact - common barrow GI-13 25.00$ CY Fill & compact - gravel base GI-14 27.00$ CY Fill & compact - screened topsoil GI-15 39.00$ CY Gabion, 12" deep, stone filled mesh GI-16 65.00$ SY Gabion, 18" deep, stone filled mesh GI-17 90.00$ SY Gabion, 36" deep, stone filled mesh GI-18 150.00$ SY Grading, fine, by hand GI-19 2.50$ SY Grading, fine, with grader GI-20 2.00$ SY 360 720.00 2886 5,772.00 845 1,690.00 Monuments, 3' Long GI-21 250.00$ Each 1 250.00 11 2,750.00 Sensitive Areas Sign GI-22 7.00$ Each 6 42.00 Sodding, 1" deep, sloped ground GI-23 8.00$ SY Surveying, line & grade GI-24 850.00$ Day 2 1,700.00 7 5,950.00 Surveying, lot location/lines GI-25 1,800.00$ Acre 6 10,800.00 Topsoil Type A (imported)GI-26 28.50$ CY Traffic control crew ( 2 flaggers )GI-27 120.00$ HR Trail, 4" chipped wood GI-28 8.00$ SY Trail, 4" crushed cinder GI-29 9.00$ SY Trail, 4" top course GI-30 12.00$ SY 415 4,980.00 Conduit, 2"GI-31 5.00$ LF Wall, retaining, concrete GI-32 55.00$ SF Wall, rockery GI-33 15.00$ SF SUBTOTAL THIS PAGE:11,570.00 33,850.00 182,634.00 (B)(C)(D)(E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR STREET AND SITE IMPROVEMENTS Quantity Remaining (Bond Reduction) (B)(C) Page 4 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.b TRANSPORTATION Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR STREET AND SITE IMPROVEMENTS Quantity Remaining (Bond Reduction) (B)(C) ROAD IMPROVEMENT/PAVEMENT/SURFACING AC Grinding, 4' wide machine < 1000sy RI-1 30.00$ SY 370 11,100.00 AC Grinding, 4' wide machine 1000-2000sy RI-2 16.00$ SY AC Grinding, 4' wide machine > 2000sy RI-3 10.00$ SY AC Removal/Disposal RI-4 35.00$ SY 370 12,950.00 Barricade, Type III ( Permanent )RI-5 56.00$ LF Guard Rail RI-6 30.00$ LF Curb & Gutter, rolled RI-7 17.00$ LF Curb & Gutter, vertical RI-8 12.50$ LF 665 8,312.50 1910 23,875.00 Curb and Gutter, demolition and disposal RI-9 18.00$ LF Curb, extruded asphalt RI-10 5.50$ LF Curb, extruded concrete RI-11 7.00$ LF Sawcut, asphalt, 3" depth RI-12 1.85$ LF 730 1,350.50 25 46.25 Sawcut, concrete, per 1" depth RI-13 3.00$ LF Sealant, asphalt RI-14 2.00$ LF Shoulder, gravel, 4" thick RI-15 15.00$ SY Sidewalk, 4" thick RI-16 38.00$ SY 380 14,440.00 910 34,580.00 807 30,666.00 Sidewalk, 4" thick, demolition and disposal RI-17 32.00$ SY Sidewalk, 5" thick RI-18 41.00$ SY Sidewalk, 5" thick, demolition and disposal RI-19 40.00$ SY Sign, Handicap RI-20 85.00$ Each Striping, per stall RI-21 7.00$ Each 7 49.00 Striping, thermoplastic, ( for crosswalk )RI-22 3.00$ SF 96 288.00 250 750.00 Striping, 4" reflectorized line RI-23 0.50$ LF 585 292.50 Additional 2.5" Crushed Surfacing RI-24 3.60$ SY HMA 1/2" Overlay 1.5" RI-25 14.00$ SY HMA 1/2" Overlay 2"RI-26 18.00$ SY 370 6,660.00 HMA Road, 2", 4" rock, First 2500 SY RI-27 28.00$ SY HMA Road, 2", 4" rock, Qty. over 2500SY RI-28 21.00$ SY HMA Road, 4", 6" rock, First 2500 SY RI-29 45.00$ SY 2070 93,150.00 790 35,550.00 HMA Road, 4", 6" rock, Qty. over 2500 SY RI-30 37.00$ SY HMA Road, 4", 4.5" ATB RI-31 38.00$ SY Gravel Road, 4" rock, First 2500 SY RI-32 15.00$ SY Gravel Road, 4" rock, Qty. over 2500 SY RI-33 10.00$ SY Thickened Edge RI-34 8.60$ LF SUBTOTAL THIS PAGE:55,393.50 152,404.00 66,262.25 (B)(C)(D)(E) Page 5 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.b TRANSPORTATION Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR STREET AND SITE IMPROVEMENTS Quantity Remaining (Bond Reduction) (B)(C) PARKING LOT SURFACING No. 2" AC, 2" top course rock & 4" borrow PL-1 21.00$ SY 2" AC, 1.5" top course & 2.5" base course PL-2 28.00$ SY 4" select borrow PL-3 5.00$ SY 1.5" top course rock & 2.5" base course PL-4 14.00$ SY SUBTOTAL PARKING LOT SURFACING: (B)(C)(D)(E) LANDSCAPING & VEGETATION No. Street Trees LA-1 300.00$ 51 15,300.00 Median Landscaping LA-2 Right-of-Way Landscaping LA-3 3.05$ SF 3420 10,431.00 3080 9,394.00 Wetland Landscaping LA-4 3.05$ SF 1156 3,525.80 SUBTOTAL LANDSCAPING & VEGETATION:10,431.00 24,694.00 3,525.80 (B)(C)(D)(E) TRAFFIC & LIGHTING No. Signs TR-1 250.00$ 19 4,750.00 5 1,250.00 Street Light System ( # of Poles)TR-2 9,500.00$ 7 66,500.00 12 114,000.00 Traffic Signal TR-3 Traffic Signal Modification TR-4 SUBTOTAL TRAFFIC & LIGHTING:66,500.00 118,750.00 1,250.00 (B)(C)(D)(E) WRITE-IN-ITEMS Modular Block Retaining Wall 25.00$ SF 1544 38,600.00 Split Rail Fencing/signage 25.00$ LF 435 10,875.00 Trail Light System (# of Poles)3,500.00$ EA 15 52,500.00 SUBTOTAL WRITE-IN ITEMS:101,975.00 STREET AND SITE IMPROVEMENTS SUBTOTAL:143,894.50 329,698.00 355,647.05 SALES TAX @ 10%14,389.45 32,969.80 35,564.71 STREET AND SITE IMPROVEMENTS TOTAL:158,283.95 362,667.80 391,211.76 (B)(C)(D)(E) Page 6 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.b TRANSPORTATION Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost DRAINAGE (CPE = Corrugated Polyethylene Pipe, N12 or Equivalent) For Culvert prices, Average of 4' cover was assumed. Assume perforated PVC is same price as solid pipe.) Access Road, R/D D-1 26.00$ SY * (CBs include frame and lid) Beehive D-2 90.00$ Each Through-curb Inlet Framework D-3 400.00$ Each CB Type I D-4 1,500.00$ Each 4 6,000.00 17 25,500.00 7 10,500.00 CB Type IL D-5 1,750.00$ Each CB Type II, 48" diameter D-6 2,300.00$ Each 1 2,300.00 8 18,400.00 2 4,600.00 for additional depth over 4' D-7 480.00$ FT CB Type II, 54" diameter D-8 2,500.00$ Each 1 2,500.00 for additional depth over 4'D-9 495.00$ FT CB Type II, 60" diameter D-10 2,800.00$ Each for additional depth over 4'D-11 600.00$ FT CB Type II, 72" diameter D-12 6,000.00$ Each for additional depth over 4'D-13 850.00$ FT CB Type II, 96" diameter D-14 14,000.00$ Each for additional depth over 4'D-15 925.00$ FT Trash Rack, 12"D-16 350.00$ Each Trash Rack, 15"D-17 410.00$ Each Trash Rack, 18"D-18 480.00$ Each Trash Rack, 21"D-19 550.00$ Each Cleanout, PVC, 4"D-20 150.00$ Each Cleanout, PVC, 6"D-21 170.00$ Each 42 7,140.00 Cleanout, PVC, 8"D-22 200.00$ Each Culvert, PVC, 4" D-23 10.00$ LF Culvert, PVC, 6" D-24 13.00$ LF 1182 15,366.00 Culvert, PVC, 8" D-25 15.00$ LF Culvert, PVC, 12" D-26 23.00$ LF Culvert, PVC, 15" D-27 35.00$ LF Culvert, PVC, 18" D-28 41.00$ LF Culvert, PVC, 24"D-29 56.00$ LF Culvert, PVC, 30" D-30 78.00$ LF Culvert, PVC, 36" D-31 130.00$ LF Culvert, CMP, 8"D-32 19.00$ LF Culvert, CMP, 12"D-33 29.00$ LF SUBTOTAL THIS PAGE:10,800.00 43,900.00 37,606.00 (B)(C)(D)(E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Quantity Remaining (Bond Reduction) (B)(C) Page 7 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Quantity Remaining (Bond Reduction) (B)(C) DRAINAGE (Continued) Culvert, CMP, 15"D-34 35.00$ LF Culvert, CMP, 18"D-35 41.00$ LF Culvert, CMP, 24"D-36 56.00$ LF Culvert, CMP, 30"D-37 78.00$ LF Culvert, CMP, 36"D-38 130.00$ LF Culvert, CMP, 48"D-39 190.00$ LF Culvert, CMP, 60"D-40 270.00$ LF Culvert, CMP, 72"D-41 350.00$ LF Culvert, Concrete, 8"D-42 42.00$ LF Culvert, Concrete, 12"D-43 48.00$ LF Culvert, Concrete, 15"D-44 78.00$ LF Culvert, Concrete, 18"D-45 48.00$ LF Culvert, Concrete, 24"D-46 78.00$ LF Culvert, Concrete, 30"D-47 125.00$ LF Culvert, Concrete, 36"D-48 150.00$ LF Culvert, Concrete, 42"D-49 175.00$ LF Culvert, Concrete, 48"D-50 205.00$ LF Culvert, CPE Triple Wall, 6" D-51 14.00$ LF Culvert, CPE Triple Wall, 8" D-52 16.00$ LF Culvert, CPE Triple Wall, 12" D-53 24.00$ LF Culvert, CPE Triple Wall, 15" D-54 35.00$ LF Culvert, CPE Triple Wall, 18" D-55 41.00$ LF Culvert, CPE Triple Wall, 24" D-56 56.00$ LF Culvert, CPE Triple Wall, 30" D-57 78.00$ LF Culvert, CPE Triple Wall, 36" D-58 130.00$ LF Culvert, LCPE, 6"D-59 60.00$ LF Culvert, LCPE, 8"D-60 72.00$ LF Culvert, LCPE, 12"D-61 84.00$ LF 761 63,924.00 238 19,992.00 Culvert, LCPE, 15"D-62 96.00$ LF Culvert, LCPE, 18"D-63 108.00$ LF 16 1,728.00 464 50,112.00 Culvert, LCPE, 24"D-64 120.00$ LF Culvert, LCPE, 30"D-65 132.00$ LF Culvert, LCPE, 36"D-66 144.00$ LF Culvert, LCPE, 48"D-67 156.00$ LF Culvert, LCPE, 54"D-68 168.00$ LF SUBTOTAL THIS PAGE:1,728.00 63,924.00 70,104.00 (B)(C)(D)(E) Page 8 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Quantity Remaining (Bond Reduction) (B)(C) DRAINAGE (Continued) Culvert, LCPE, 60"D-69 180.00$ LF Culvert, LCPE, 72"D-70 192.00$ LF Culvert, HDPE, 6"D-71 42.00$ LF Culvert, HDPE, 8"D-72 42.00$ LF Culvert, HDPE, 12"D-73 74.00$ LF Culvert, HDPE, 15"D-74 106.00$ LF Culvert, HDPE, 18"D-75 138.00$ LF Culvert, HDPE, 24"D-76 221.00$ LF Culvert, HDPE, 30"D-77 276.00$ LF Culvert, HDPE, 36"D-78 331.00$ LF Culvert, HDPE, 48"D-79 386.00$ LF Culvert, HDPE, 54"D-80 441.00$ LF Culvert, HDPE, 60"D-81 496.00$ LF Culvert, HDPE, 72"D-82 551.00$ LF Pipe, Polypropylene, 6"D-83 84.00$ LF Pipe, Polypropylene, 8"D-84 89.00$ LF Pipe, Polypropylene, 12"D-85 95.00$ LF Pipe, Polypropylene, 15"D-86 100.00$ LF Pipe, Polypropylene, 18"D-87 106.00$ LF Pipe, Polypropylene, 24"D-88 111.00$ LF Pipe, Polypropylene, 30"D-89 119.00$ LF Pipe, Polypropylene, 36"D-90 154.00$ LF Pipe, Polypropylene, 48"D-91 226.00$ LF Pipe, Polypropylene, 54"D-92 332.00$ LF Pipe, Polypropylene, 60"D-93 439.00$ LF Pipe, Polypropylene, 72"D-94 545.00$ LF Culvert, DI, 6"D-95 61.00$ LF Culvert, DI, 8"D-96 84.00$ LF Culvert, DI, 12"D-97 106.00$ LF 68 7,208.00 206 21,836.00 Culvert, DI, 15"D-98 129.00$ LF Culvert, DI, 18"D-99 152.00$ LF 342 51,984.00 Culvert, DI, 24"D-100 175.00$ LF Culvert, DI, 30"D-101 198.00$ LF Culvert, DI, 36"D-102 220.00$ LF Culvert, DI, 48"D-103 243.00$ LF Culvert, DI, 54"D-104 266.00$ LF Culvert, DI, 60"D-105 289.00$ LF Culvert, DI, 72"D-106 311.00$ LF SUBTOTAL THIS PAGE:7,208.00 73,820.00 (B)(C)(D)(E) Page 9 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Quantity Remaining (Bond Reduction) (B)(C) Specialty Drainage Items Ditching SD-1 9.50$ CY Flow Dispersal Trench (1,436 base+)SD-3 28.00$ LF French Drain (3' depth)SD-4 26.00$ LF Geotextile, laid in trench, polypropylene SD-5 3.00$ SY Mid-tank Access Riser, 48" dia, 6' deep SD-6 2,000.00$ Each Pond Overflow Spillway SD-7 16.00$ SY Restrictor/Oil Separator, 12"SD-8 1,150.00$ Each Restrictor/Oil Separator, 15"SD-9 1,350.00$ Each Restrictor/Oil Separator, 18"SD-10 1,700.00$ Each Riprap, placed SD-11 42.00$ CY Tank End Reducer (36" diameter)SD-12 1,200.00$ Each Infiltration pond testing SD-13 125.00$ HR Permeable Pavement SD-14 Permeable Concrete Sidewalk SD-15 Culvert, Box __ ft x __ ft SD-16 SUBTOTAL SPECIALTY DRAINAGE ITEMS: (B)(C)(D)(E) STORMWATER FACILITIES (Include Flow Control and Water Quality Facility Summary Sheet and Sketch) Detention Pond SF-1 Each Detention Tank SF-2 Each Detention Vault SF-3 Each Infiltration Pond SF-4 Each Infiltration Tank SF-5 Each Infiltration Vault SF-6 Each Infiltration Trenches SF-7 Each Basic Biofiltration Swale SF-8 Each Wet Biofiltration Swale SF-9 Each Wetpond SF-10 Each Wetvault SF-11 Each Sand Filter SF-12 Each Sand Filter Vault SF-13 Each Linear Sand Filter SF-14 Each Proprietary Facility SF-15 Each Bioretention Facility SF-16 Each SUBTOTAL STORMWATER FACILITIES: (B)(C)(D)(E) Page 10 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Quantity Remaining (Bond Reduction) (B)(C) WRITE-IN-ITEMS (INCLUDE ON-SITE BMPs) WI-1 WI-2 WI-3 WI-4 WI-5 WI-6 WI-7 WI-8 WI-9 WI-10 WI-11 WI-12 WI-13 WI-14 WI-15 SUBTOTAL WRITE-IN ITEMS: DRAINAGE AND STORMWATER FACILITIES SUBTOTAL:19,736.00 181,644.00 107,710.00 SALES TAX @ 10%1,973.60 18,164.40 10,771.00 DRAINAGE AND STORMWATER FACILITIES TOTAL:21,709.60 199,808.40 118,481.00 (B) (C) (D) (E) Page 11 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Connection to Existing Watermain W-1 2,000.00$ Each Ductile Iron Watermain, CL 52, 4 Inch Diameter W-2 50.00$ LF Ductile Iron Watermain, CL 52, 6 Inch Diameter W-3 56.00$ LF Ductile Iron Watermain, CL 52, 8 Inch Diameter W-4 60.00$ LF Ductile Iron Watermain, CL 52, 10 Inch Diameter W-5 70.00$ LF Ductile Iron Watermain, CL 52, 12 Inch Diameter W-6 80.00$ LF Gate Valve, 4 inch Diameter W-7 500.00$ Each Gate Valve, 6 inch Diameter W-8 700.00$ Each Gate Valve, 8 Inch Diameter W-9 800.00$ Each Gate Valve, 10 Inch Diameter W-10 1,000.00$ Each Gate Valve, 12 Inch Diameter W-11 1,200.00$ Each Fire Hydrant Assembly W-12 4,000.00$ Each Permanent Blow-Off Assembly W-13 1,800.00$ Each Air-Vac Assembly, 2-Inch Diameter W-14 2,000.00$ Each Air-Vac Assembly, 1-Inch Diameter W-15 1,500.00$ Each Compound Meter Assembly 3-inch Diameter W-16 8,000.00$ Each Compound Meter Assembly 4-inch Diameter W-17 9,000.00$ Each Compound Meter Assembly 6-inch Diameter W-18 10,000.00$ Each Pressure Reducing Valve Station 8-inch to 10-inch W-19 20,000.00$ Each WATER SUBTOTAL: SALES TAX @ 10% WATER TOTAL: (B) (C) (D) (E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR WATER Quantity Remaining (Bond Reduction) (B)(C) Page 12 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.d WATER Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 CED Permit #:C20-005641 Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Clean Outs SS-1 1,000.00$ Each Grease Interceptor, 500 gallon SS-2 8,000.00$ Each Grease Interceptor, 1000 gallon SS-3 10,000.00$ Each Grease Interceptor, 1500 gallon SS-4 15,000.00$ Each Side Sewer Pipe, PVC. 4 Inch Diameter SS-5 80.00$ LF Side Sewer Pipe, PVC. 6 Inch Diameter SS-6 95.00$ LF Sewer Pipe, PVC, 8 inch Diameter SS-7 105.00$ LF Sewer Pipe, PVC, 12 Inch Diameter SS-8 120.00$ LF Sewer Pipe, DI, 8 inch Diameter SS-9 115.00$ LF Sewer Pipe, DI, 12 Inch Diameter SS-10 130.00$ LF Manhole, 48 Inch Diameter SS-11 6,000.00$ Each Manhole, 54 Inch Diameter SS-13 6,500.00$ Each Manhole, 60 Inch Diameter SS-15 7,500.00$ Each Manhole, 72 Inch Diameter SS-17 8,500.00$ Each Manhole, 96 Inch Diameter SS-19 14,000.00$ Each Pipe, C-900, 12 Inch Diameter SS-21 180.00$ LF Outside Drop SS-24 1,500.00$ LS Inside Drop SS-25 1,000.00$ LS Sewer Pipe, PVC, ____ Inch Diameter SS-26 Lift Station (Entire System)SS-27 LS SANITARY SEWER SUBTOTAL: SALES TAX @ 10% SANITARY SEWER TOTAL: (B) (C) (D) (E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR SANITARY SEWER Quantity Remaining (Bond Reduction) (B)(C) Page 13 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.e SANITARY SEWER Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 Planning Division |1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430-7200 Date: Name:Project Name: PE Registration No:CED Plan # (LUA): Firm Name:CED Permit # (U): Firm Address:Site Address: Phone No.Parcel #(s): Email Address:Project Phase: Site Restoration/Erosion Sediment Control Subtotal (a) Existing Right-of-Way Improvements Subtotal (b)(b)158,283.95$ Future Public Improvements Subtotal (c)362,667.80$ Stormwater & Drainage Facilities (Public & Private) Subtotal (d)(d)339,999.00$ (e) (f) Site Restoration Civil Construction Permit Maintenance Bond 172,190.15$ Bond Reduction 2 Construction Permit Bond Amount 3 Minimum Bond Amount is $10,000.00 1 Estimate Only - May involve multiple and variable components, which will be established on an individual basis by Development Engineering. 2 The City of Renton allows one request only for bond reduction prior to the maintenance period. Reduction of not more than 70% of the original bond amount, provided that the remaining 30% will cover all remaining items to be constructed. 3 Required Bond Amounts are subject to review and modification by Development Engineering. * Note: The word BOND as used in this document means any financial guarantee acceptable to the City of Renton. ** Note: All prices include labor, equipment, materials, overhead and profit. 425-251-6222 Btalkington@barghausen.com Elliott Farms 15-000242 14207 Maple Valley RD Renton, WA 98058 222305-9004 FOR APPROVAL C20-005641 18215 72nd Ave S Kent, WA 98032 687,918.83$ P (a) x 100% SITE IMPROVEMENT BOND QUANTITY WORKSHEET BOND CALCULATIONS 4/20/2021 Barry Talkington 41423 Barghausen Consulting Engineers Inc. R ((b x 150%) + (d x 100%)) S (e) x 150% + (f) x 100% Bond Reduction: Existing Right-of-Way Improvements (Quantity Remaining)2 Bond Reduction: Stormwater & Drainage Facilities (Quantity Remaining)2 T (P +R - S) Prepared by:Project Information CONSTRUCTION BOND AMOUNT */** (prior to permit issuance) EST1 ((b) + (c) + (d)) x 20% -$ MAINTENANCE BOND */** (after final acceptance of construction) 110,493.90$ 158,283.95$ 577,424.93$ 110,493.90$ -$ 339,999.00$ -$ Page 14 of 14 Ref 8-H Bond Quantity Worksheet SECTION III. BOND WORKSHEET Unit Prices Updated: 06/14/2016 Version: 04/26/2017 Printed 4/21/2021 Tab 10.0 21397.002-TIR 10.0 OPERATIONS AND MAINTENANCE MANUAL The Elliott Farms project does not contain any drainage or water quality facilities on-site. The project is utilizing an existing off-site water quality wetpond that has been built for the developed flows from the project and is currently being maintained by the city of Renton. The onsite conveyance system consists of a series of catch basins and storm pipe which direct stormwater flows to the existing off-site water quality facility. The onsite conveyance systems within the future right-of-way and public drainage easements will be maintained by the city of Renton. The future right-of-way is depicted as Road A. The catch basins and storm pipes located within the private alley’s, shown as Tracts B, C and E will be owned and maintained by the homeowner’s association. The individual lot storm stubs outside the right-of-way and the catch basins and storm pipes in Tracts A and F will be maintained by the homeowner’s association. The drainage system along WA-169 consisting of a series of catch basins and storm pipes that outlet to the existing ditch, will be owned and maintained by the city of Renton. Maintenance of the stormwater facilities in the areas that will be owned and maintained by the homeowner’s association will be conducted on an annual basis or as pre-scribed in the maintenance requirements shown in this section. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-10 NO. 5 – CATCH BASINS AND MANHOLES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Structure Sediment accumulation Sediment exceeds 60% of the depth from the bottom of the catch basin to the invert of the lowest pipe into or out of the catch basin or is within 6 inches of the invert of the lowest pipe into or out of the catch basin. Sump of catch basin contains no sediment. Trash and debris Trash or debris of more than ½ cubic foot which is located immediately in front of the catch basin opening or is blocking capacity of the catch basin by more than 10%. No Trash or debris blocking or potentially blocking entrance to catch basin. Trash or debris in the catch basin that exceeds 1/3 the depth from the bottom of basin to invert the lowest pipe into or out of the basin. No trash or debris in the catch basin. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases (e.g., methane). No dead animals or vegetation present within catch basin. Deposits of garbage exceeding 1 cubic foot in volume. No condition present which would attract or support the breeding of insects or rodents. Damage to frame and/or top slab Corner of frame extends more than ¾ inch past curb face into the street (If applicable). Frame is even with curb. Top slab has holes larger than 2 square inches or cracks wider than ¼ inch. Top slab is free of holes and cracks. Frame not sitting flush on top slab, i.e., separation of more than ¾ inch of the frame from the top slab. Frame is sitting flush on top slab. Cracks in walls or bottom Cracks wider than ½ inch and longer than 3 feet, any evidence of soil particles entering catch basin through cracks, or maintenance person judges that catch basin is unsound. Catch basin is sealed and is structurally sound. Cracks wider than ½ inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. No cracks more than 1/4 inch wide at the joint of inlet/outlet pipe. Settlement/ misalignment Catch basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Basin replaced or repaired to design standards. Damaged pipe joints Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering the catch basin at the joint of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of inlet/outlet pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Inlet/Outlet Pipe Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-11 NO. 5 – CATCH BASINS AND MANHOLES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Inlet/Outlet Pipe (cont.) Damaged inlet/outlet pipe Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. Metal Grates (Catch Basins) Unsafe grate opening Grate with opening wider than 7/8 inch. Grate opening meets design standards. Trash and debris Trash and debris that is blocking more than 20% of grate surface. Grate free of trash and debris. footnote to guidelines for disposal Damaged or missing grate Grate missing or broken member(s) of the grate. Any open structure requires urgent maintenance. Grate is in place and meets design standards. Manhole Cover/Lid Cover/lid not in place Cover/lid is missing or only partially in place. Any open structure requires urgent maintenance. Cover/lid protects opening to structure. Locking mechanism not working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Cover/lid difficult to remove One maintenance person cannot remove cover/lid after applying 80 lbs. of lift. Cover/lid can be removed and reinstalled by one maintenance person. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-12 NO. 6 – CONVEYANCE PIPES AND DITCHES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Pipes Sediment & debris accumulation Accumulated sediment or debris that exceeds 20% of the diameter of the pipe. Water flows freely through pipes. Vegetation/root growth in pipe Vegetation/roots that reduce free movement of water through pipes. Water flows freely through pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Damage to protective coating or corrosion Protective coating is damaged; rust or corrosion is weakening the structural integrity of any part of pipe. Pipe repaired or replaced. Damaged pipes Any dent that decreases the cross section area of pipe by more than 20% or is determined to have weakened structural integrity of the pipe. Pipe repaired or replaced. Ditches Trash and debris Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Trash and debris cleared from ditches. Sediment accumulation Accumulated sediment that exceeds 20% of the design depth. Ditch cleaned/flushed of all sediment and debris so that it matches design. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to City personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where City personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Excessive vegetation growth Vegetation that reduces free movement of water through ditches. Water flows freely through ditches. Erosion damage to slopes Any erosion observed on a ditch slope. Slopes are not eroding. Rock lining out of place or missing (If applicable) One layer or less of rock exists above native soil area 5 square feet or more, any exposed native soil. Replace rocks to design standards. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-13 NO. 7 – DEBRIS BARRIERS (E.G., TRASH RACKS) MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED. Site Trash and debris Trash or debris plugging more than 20% of the area of the barrier. Barrier clear to receive capacity flow. Sediment accumulation Sediment accumulation of greater than 20% of the area of the barrier Barrier clear to receive capacity flow. Structure Cracked, broken, or loose pipe or structure Structure which bars attached to is damaged – pipe is loose or cracked or concrete structure is cracked, broken, or loose. Structure barrier attached to is sound. Bars Incorrect bar spacing Bar spacing exceeds 6 inches. Bars have at most 6 inches spacing. Damaged or missing bars Bars are bent out of shape more than 3 inches. Bars in place with no bends more than ¾ inch. Bars are missing or entire barrier missing. Bars in place according to design. Bars are loose and rust is causing 50% deterioration to any part of barrier. Repair or replace barrier to design standards. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-14 NO. 8 – ENERGY DISSIPATERS MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED. Site Trash and debris Trash and/or debris accumulation. Dissipater clear of trash and/or debris. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Rock Pad Missing or moved rock Only one layer of rock exists above native soil in area five square feet or larger or any exposure of native soil. Rock pad prevents erosion. Dispersion Trench Pipe plugged with sediment Accumulated sediment that exceeds 20% of the design depth. Pipe cleaned/flushed so that it matches design. Not discharging water properly Visual evidence of water discharging at concentrated points along trench (normal condition is a “sheet flow” of water along trench). Water discharges from feature by sheet flow. Perforations plugged Over 1/4 of perforations in pipe are plugged with debris or sediment. Perforations freely discharge flow. Water flows out top of “distributor” catch basin. Water flows out of distributor catch basin during any storm less than the design storm. No flow discharges from distributor catch basin. Receiving area over-saturated Water in receiving area is causing or has potential of causing landslide problems. No danger of landslides. Gabions Damaged mesh Mesh of gabion broken, twisted or deformed so structure is weakened or rock may fall out. Mesh is intact, no rock missing. Corroded mesh Gabion mesh shows corrosion through more than ¼ of its gage. All gabion mesh capable of containing rock and retaining designed form. Collapsed or deformed baskets Gabion basket shape deformed due to any cause. All gabion baskets intact, structure stands as designed. Missing rock Any rock missing that could cause gabion to loose structural integrity. No rock missing. Manhole/Chamber Worn or damaged post, baffles or side of chamber Structure dissipating flow deteriorates to ½ or original size or any concentrated worn spot exceeding one square foot which would make structure unsound. Structure is in no danger of failing. Damage to wall, frame, bottom, and/or top slab Cracks wider than ½-inch or any evidence of soil entering the structure through cracks, or maintenance inspection personnel determines that the structure is not structurally sound. Manhole/chamber is sealed and structurally sound. Damaged pipe joints Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering the structure at the joint of the inlet/outlet pipes. No soil or water enters and no water discharges at the joint of inlet/outlet pipes. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-15 NO. 9 – FENCING MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Erosion or holes under fence Erosion or holes more than 4 inches high and 12-18 inches wide permitting access through an opening under a fence. No access under the fence. Wood Posts, Boards and Cross Members Missing or damaged parts Missing or broken boards, post out of plumb by more than 6 inches or cross members broken No gaps on fence due to missing or broken boards, post plumb to within 1½ inches, cross members sound. Weakened by rotting or insects Any part showing structural deterioration due to rotting or insect damage All parts of fence are structurally sound. Damaged or failed post foundation Concrete or metal attachments deteriorated or unable to support posts. Post foundation capable of supporting posts even in strong wind. Metal Posts, Rails and Fabric Damaged parts Post out of plumb more than 6 inches. Post plumb to within 1½ inches. Top rails bent more than 6 inches. Top rail free of bends greater than 1 inch. Any part of fence (including post, top rails, and fabric) more than 1 foot out of design alignment. Fence is aligned and meets design standards. Missing or loose tension wire. Tension wire in place and holding fabric. Deteriorated paint or protective coating Part or parts that have a rusting or scaling condition that has affected structural adequacy. Structurally adequate posts or parts with a uniform protective coating. Openings in fabric Openings in fabric are such that an 8-inch diameter ball could fit through. Fabric mesh openings within 50% of grid size. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-16 NO. 10 – GATES/BOLLARDS/ACCESS BARRIERS MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Chain Link Fencing Gate Damaged or missing members Missing gate. Gates in place. Broken or missing hinges such that gate cannot be easily opened and closed by a maintenance person. Hinges intact and lubed. Gate is working freely. Gate is out of plumb more than 6 inches and more than 1 foot out of design alignment. Gate is aligned and vertical. Missing stretcher bar, stretcher bands, and ties. Stretcher bar, bands, and ties in place. Locking mechanism does not lock gate Locking device missing, no-functioning or does not link to all parts. Locking mechanism prevents opening of gate. Openings in fabric Openings in fabric are such that an 8-inch diameter ball could fit through. Fabric mesh openings within 50% of grid size. Bar Gate Damaged or missing cross bar Cross bar does not swing open or closed, is missing or is bent to where it does not prevent vehicle access. Cross bar swings fully open and closed and prevents vehicle access. Locking mechanism does not lock gate Locking device missing, no-functioning or does not link to all parts. Locking mechanism prevents opening of gate. Support post damaged Support post does not hold cross bar up. Cross bar held up preventing vehicle access into facility. Bollards Damaged or missing bollards Bollard broken, missing, does not fit into support hole or hinge broken or missing. No access for motorized vehicles to get into facility. Bollards do not lock Locking assembly or lock missing or cannot be attached to lock bollard in place. No access for motorized vehicles to get into facility. Boulders Dislodged boulders Boulders not located to prevent motorized vehicle access. No access for motorized vehicles to get into facility. Evidence of vehicles circumventing boulders Motorized vehicles going around or between boulders. No access for motorized vehicles to get into facility. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-17 NO. 11 – GROUNDS (LANDSCAPING) MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Any trash and debris which exceed 1 cubic foot per 1,000 square feet (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In general, there should be no visual evidence of dumping. Trash and debris cleared from site. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to City personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where City personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Excessive growth of grass/groundcover Grass or groundcover exceeds 18 inches in height. Grass or groundcover mowed to a height no greater than 6 inches. Trees and Shrubs Hazard tree identified Any tree or limb of a tree identified as having a potential to fall and cause property damage or threaten human life. A hazard tree identified by a qualified arborist must be removed as soon as possible. No hazard trees in facility. Damaged tree or shrub identified Limbs or parts of trees or shrubs that are split or broken which affect more than 25% of the total foliage of the tree or shrub. Trees and shrubs with less than 5% of total foliage with split or broken limbs. Trees or shrubs that have been blown down or knocked over. No blown down vegetation or knocked over vegetation. Trees or shrubs free of injury. Trees or shrubs which are not adequately supported or are leaning over, causing exposure of the roots. Tree or shrub in place and adequately supported; dead or diseased trees removed. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-18 NO. 12 – ACCESS ROADS MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Trash and debris exceeds 1 cubic foot per 1,000 square feet (i.e., trash and debris would fill up one standards size garbage can). Roadway drivable by maintenance vehicles. Debris which could damage vehicle tires or prohibit use of road. Roadway drivable by maintenance vehicles. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Blocked roadway Any obstruction which reduces clearance above road surface to less than 14 feet. Roadway overhead clear to 14 feet high. Any obstruction restricting the access to a 10- to 12 foot width for a distance of more than 12 feet or any point restricting access to less than a 10 foot width. At least 12-foot of width on access road. Road Surface Erosion, settlement, potholes, soft spots, ruts Any surface defect which hinders or prevents maintenance access. Road drivable by maintenance vehicles. Vegetation on road surface Trees or other vegetation prevent access to facility by maintenance vehicles. Maintenance vehicles can access facility. Shoulders and Ditches Erosion Erosion within 1 foot of the roadway more than 8 inches wide and 6 inches deep. Shoulder free of erosion and matching the surrounding road. Weeds and brush Weeds and brush exceed 18 inches in height or hinder maintenance access. Weeds and brush cut to 2 inches in height or cleared in such a way as to allow maintenance access. Modular Grid Pavement Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Damaged or missing blocks/grids Access surface compacted because of broken on missing modular block. Access road surface restored so road infiltrates. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-39 NO. 27 – GRAVEL FILLED DISPERSION TRENCH BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Preventive Blocking, obstructions Debris or trash limiting flow to dispersion trench or preventing spreader function. Dispersion trench able to receive full flow prior to and during wet season. Site Trash and debris Trash or debris that could end up in the dispersion trench is evident. No trash or debris that could get into the dispersion trench can be found. Pipes Plugged inlet The entrance to the pipe is restricted due to sediment, trash, or debris. The entrance to the pipe is not restricted. Vegetation/root growth in pipes Vegetation/roots that reduce free movement of water through pipes. Water flows freely through pipes. Plugged pipe Sediment or other material prevents free flow of water through the pipe. Water flows freely through pipes. Broken pipe or joint leaks. Damage to the pipe or pipe joints allowing water to seep out. Pipe does not allow water to exit other than at the outlet to the trench. Broken or missing cleanout caps Cleanout caps are broken, missing, or buried. Cleanout caps are accessible and intact. Structure Flow not reaching trench Flows are not getting into the trench as designed. Water enters and exits trench as designed. Perforated pipe plugged Flow not able to enter or properly exit from perforated pipe. Water freely enters and exits perforated pipe. Flow not spreading evenly at outlet of trench Outlet flows channelizing or not spreading evenly from trench. Sheet flow occurs at the outlet of the trench. Cleanout/inspection access does not allow cleaning or inspection of perforated pipe The cleanout/inspection access is not available. Cleanout/inspection access is available. Filter Media Plugged filter media Filter media plugged. Flow through filter media is normal. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-40 NO. 28 – NATIVE VEGETATED SURFACE/NATIVE VEGETATED LANDSCAPE BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Trash and debris accumulated on the native vegetated surface/native vegetated landscape site. Native vegetated surface site free of any trash or debris. Vegetation Insufficient vegetation Less than two species each of native trees, shrubs, and groundcover occur in the design area. A minimum of two species each of native trees, shrubs, and groundcover is established and healthy. Poor vegetation coverage Less than 90% if the required vegetated area has healthy growth. A minimum of 90% of the required vegetated area has healthy growth. Undesirable vegetation present Weeds, blackberry, and other undesirable plants are invading more than 10% of vegetated area. Less than 10% undesirable vegetation occurs in the required native vegetated surface area. Vegetated Area Soil compaction Soil in the native vegetation area compacted. Less than 8% of native vegetation area is compacted. Insufficient vegetation Less than 3.5 square feet of native vegetation area for every 1 square foot of impervious surface. A minimum of 3.5 square feet of native vegetation area for every 1 square foot of impervious surface. Excess slope Slope of native vegetation area greater than 15%. Slope of native growth area does not exceed 15%. NO. 29 – PERFORATED PIPE CONNECTIONS BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Preventive Blocking, obstructions Debris or trash limiting flow into perforated pipe system or outfall of BMP is plugged or otherwise nonfunctioning. Outfall of BMP is receiving designed flows from perforated pipe connection. Inflow Inflow impeded Inflow into the perforated pipe is partially or fully blocked or altered to prevent flow from getting into the pipe. Inflow to the perforated pipe is unimpeded. Pipe Trench Area Surface compacted Ground surface over the perforated pipe trench is compacted or covered with impermeable material. Ground surface over the perforated pipe is not compacted and free of any impervious cover. Outflow Outflow impeded Outflow from the perforated pipe into the public drainage system is blocked. Outflow to the public drainage system is unimpeded. Outfall Area Erosion or landslides Existence of the perforated pipe is causing or exasperating erosion or landslides. Perforated pipe system is sealed off and an alternative BMP is implemented. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-43 NO. 32 – RAINWATER HARVESTING BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Preventive Insufficient storage volume No rain water in storage unit at the beginning of the rain season. Maximum storage available at the beginning of the rain season (Oct. 1). Collection Area Trash and debris Trash of debris on collection area may plug filter system Collection area clear of trash and debris. Filter Restricted or plugged filter Filter is partially or fully plugged preventing water from getting in to the storage unit. Filter is allowing collection water into storage unit. NO. 33 – ROCK PAD BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Trash and debris accumulated on rock pad site. Rock pad site free of any trash or debris. Rock Pad Area Insufficient rock pad size Rock pad is not 2 feet by 3 feet by 6 inches thick or as designed. Rock pad is 2 feet by 3 feet by 6 inches thick or as designed. Vegetation growth Vegetation is seen growing in or through rock pad. No vegetation within rock pad area. Rock Exposed soil Soil can be seen through the rock pad. Full thickness of the rock pad is in place, no soil visible through rock pad. NO. 34 – SHEET FLOW BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Trash and debris accumulated on the sheet flow site. Sheet flow site free of any trash or debris. Sheet flow area Erosion Soil erosion occurring in sheet flow zone. Soil erosion is not occurring and rills and channels have been repaired. Concentrated flow Sheet flow is not occurring in the sheet flow zone. Sheet flow area is regraded to provide sheet flow. NO. 35 – SPLASH BLOCK BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Trash and debris accumulated on the splash block. Splash block site free of any trash or debris. Splash Block Dislodged splash block Splash block moved from outlet of downspout. Splash block correctly positioned to catch discharge from downspout. Channeling Water coming off the splash block causing erosion. No erosion occurs from the splash block. Downspout water misdirected Water coming from the downspout is not discharging to the dispersal area. Water is discharging normally to the dispersal area. N/A APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-47 NO. 38 – SOIL AMENDMENT BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Soil Media Unhealthy vegetation Vegetation not fully covering ground surface or vegetation health is poor. Yellowing: possible Nitrogen (N) deficiency. Poor growth: possible Phosphorous (P) deficiency. Poor flowering, spotting or curled leaves, or weak roots or stems: possible Potassium (K) deficiency. Plants are healthy and appropriate for site conditions Inadequate soil nutrients and structure In the fall, return leaf fall and shredded woody materials from the landscape to the site when possible Soil providing plant nutrients and structure Excessive vegetation growth Grass becomes excessively tall (greater than 10 inches); nuisance weeds and other vegetation start to take over. Healthy turf- “grasscycle” (mulch-mow or leave the clippings) to build turf health Weeds Preventive maintenance Avoid use of pesticides (bug and weed killers), like “weed & feed,” which damage the soil Fertilizer needed Where fertilization is needed (mainly turf and annual flower beds), a moderate fertilization program should be used which relies on compost, natural fertilizers or slow-release synthetic balanced fertilizers Integrated Pest Management (IPM) protocols for fertilization followed Bare spots Bare spots on soil No bare spots, area covered with vegetation or mulch mixed into the underlying soil. Compaction Poor infiltration due to soil compaction • To remediate compaction, aerate soil, till to at least 8-inch depth, or further amend soil with compost and re-till • If areas are turf, aerate compacted areas and top dress them with 1/4 to 1/2 inch of compost to renovate them • If drainage is still slow, consider investigating alternative causes (e.g., high wet season groundwater levels, low permeability soils) • Also consider site use and protection from compacting activities No soil compaction Poor infiltration Soils become waterlogged, do not appear to be infiltrating. Facility infiltrating properly Erosion/Scouring Erosion Areas of potential erosion are visible Causes of erosion (e.g., concentrate flow entering area, channelization of runoff) identified and damaged area stabilized (regrade, rock, vegetation, erosion control matting).For deep channels or cuts (over 3 inches in ponding depth), temporary erosion control measures in place until permanent repairs can be made Grass/Vegetation Unhealthy vegetation Less than 75% of planted vegetation is healthy with a generally good appearance. Healthy vegetation. Unhealthy plants removed/replaced. Appropriate vegetation planted in terms of exposure, soil and soil moisture. Noxious Weeds Noxious weeds Listed noxious vegetation is present (refer to current County noxious weed list). No noxious weeds present. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-48 NO. 39 – RETAINED TREES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Tree Dead or declining Dead, damaged, or declining Tree replaced per planting plan or acceptable substitute NO. 40 – FILTERRA SYSTEM MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED In addition to the specific maintenance criteria provided below, all manufacturer’s requirements shall be followed. Facility – General Requirements Life cycle Once per year, except mulch and trash removal twice per year Facility is re-inspected and any needed maintenance performed Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries, or paint Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Inlet Excessive sediment or trash accumulation Accumulated sediments or trash impair free flow of water into system Inlet should be free of obstructions allowing free distributed flow of water into system Mulch Cover Trash and floatable debris accumulation Excessive trash and/or debris accumulation Minimal trash or other debris on mulch cover. Mulch cover raked level. “Ponding” of water on mulch cover “Ponding” in unit could be indicative of clogging due to excessive fine sediment accumulation or spill of petroleum oils Stormwater should drain freely and evenly through mulch cover Proprietary Filter Media/ Vegetation Substrate “Ponding” of water on mulch cover after mulch cover has been maintained Excessive fine sediment passes the mulch cover and clogs the filter media/vegetative substrate Stormwater should drain freely and evenly through mulch cover. Replace substrate and vegetation when needed Vegetation Plants not growing or in poor condition Soil/mulch too wet, evidence of spill, incorrect plant selection, pest infestation, and/or vandalism to plants Plants should be healthy and pest free Media/mulch too dry Irrigation is required Plants absent Plants absent Appropriate plants are present Excessive plant growth Excessive plant growth inhibits facility function or becomes a hazard for pedestrian and vehicular circulation and safety Pruning and/or thinning vegetation maintains proper plant density. Appropriate plants are present. Structure Structure has visible cracks Cracks wider than ½ inch Evidence of soil particles entering the structure through the cracks Structure is sealed and structurally sound N/A Appendix A Appendix A Lower Cedar River Basin and Nonpoint Pollution Action Plan XSITE