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HomeMy WebLinkAboutF_Aberdeen Avenue Short Plat_Technical Information Report_180131.pdfDEVELOPMENT ENGINEERINGIFitz-James 01/30/2018SURFACE WATER UTILITYrstraka 01/31/2018 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Table of Contents TIR Section I – Project Overview TIR Section II – Conditions and Requirements Summary TIR Section III – Off Site Analysis TIR Section IV – Flow Control and Water Quality Facility Analysis and Design TIR Section V – Conveyance System Analysis and Design TIR Section VI – Special Reports and Studies TIR Section VII – Other Permits TIR Section VIII – CSWPPP Analysis and Design TIR Section IX – Bond Quantities, Facility Summaries, and Declaration of Covenant TIR Section X – Operation and Maintenance Manual Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section I, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section I – Project Overview TIR Section I Summary Narrative List of Figures: 1. TIR Worksheet 2. Site Location 3. Aerial Photograph Map 4. Site Drainage, Drainage Basins, Sub-basins, and Site Characteristics 5. Soils The project proposes to subdivide a single 16,161 sf parcel in the R-8 zone into 2 individual single-family lots. The site currently contains one single-family home with a detached garage and a detached accessory building. The existing structures will be demolished in order to add an access and utility tract, and a house on the back lot. The project will add more than 2,000 sf of impervious surfaces and will therefore address Full Drainage requirements from the 2017 Renton Surface Water Design Manual (RSWDM). Lots 1 and 2 will be developed in the future. Stormwater requirements are addressed as part of this project for the driveway tract and for the future lots. Address: 1824 Aberdeen Ave NE, Renton, WA 98056 Tax Parcel Number: 334390-1606 The existing lot will be divided as follows: Proposed Short Plat Coverage Lot 1: 5,677 sf (0.130 ac) Lot 2: 7,903 sf (0.181 ac) Tract: 2,581 sf (0.059 ac) Total: 16,161 sf (0.370 ac) Flow Control per Core Requirement #3 must be evaluated for this site because over 5,000 sf of new plus replaced impervious surface will be created. The project falls within the City’s Flow Control Duration Standard (Forested Conditions). However, the project is exempt from the facility requirement because there is no more than a 0.15-cfs difference (when modeled using 15-minute time steps) in the 100-year peak flow. Please see Section IV for the Western Washington Hydrology Model report and assumptions. Flow Control Best Management Practices (BMPs) must be addressed per Core Requirement #9 to mitigate stormwater runoff impacts because the site adds and/or replaces more than 2,000 square feet of impervious surface. Flow Control BMPs were evaluated for the access/utility tract per Section 1.2.9.3.2 “Small Road Improvement and Urban Road Improvement BMP Requirements) and for the individual lots per Section 1.2.9.2.1 “Small Lot BMP Requirements.” A single infiltration trench is proposed to meet the requirements for the access/utility tract and for both lots. Please see Section IV for the infiltration trench sizing and assumptions. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section I, Page 2 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure I-1: Technical Information Report (TIR) Worksheet See attached pages. KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Part 2 PROJECT LOCATION AND DESCRIPTION Project Owner ___________________________ Phone _________________________________ Address _______________________________ _______________________________________ Project Engineer _________________________ Company ______________________________ Phone _________________________________ Project Name _________________________ DPER Permit # ________________________ Location Township ______________ Range ________________ Section ________________ Site Address __________________________ _____________________________________ Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS  Landuse (e.g.,Subdivision / Short Subd. / UPD)  Building (e.g.,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 Site Improvement Plan (Engr. Plans) Type of Drainage Review (check one): Date (include revision dates): Date of Final:  Full  Targeted  Simplified  Large Project  Directed __________________ __________________ __________________ Plan Type (check one): Date (include revision dates): Date of Final:  Full  Modified  Simplified __________________ __________________ __________________ Part 6 SWDM ADJUSTMENT APPROVALS Type (circle one): Standard / Experimental / Blanket Description: (include conditions in TIR Section 2) ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ Approved Adjustment No. ______________________ Date of Approval: ______________________ 2016 Surface Water Design Manual 4/24/2016 1 Prime Metropolis Properties, Inc. 925.377.8882 950 Taraval St. San Francisco, CA 94116 Greg Guillen CG Engineering 425.778.8500 Aberdeen Subdivision 23 5 1824 Aberdeen Ave NE Renton, WA 98056 x x 5 x Land Use Permit Master Application Adjustment to omit presettling cell or facility for a proprietary water quality facility per Section 6.1.1 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes / No Start Date: _______________________ Completion Date: _______________________ Describe: _________________________________ _________________________________________ _________________________________________ Re: KCSWDM Adjustment No. ________________ Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : ____________________________________________________________________ Special District Overlays: ______________________________________________________________ Drainage Basin: _____________________________________________________________________ Stormwater Requirements: ____________________________________________________________ Part 9 ONSITE AND ADJACENT SENSITIVE AREAS  River/Stream ________________________  Lake ______________________________  Wetlands ____________________________  Closed Depression ____________________  Floodplain ___________________________  Other _______________________________ _______________________________  Steep Slope __________________________  Erosion Hazard _______________________  Landslide Hazard ______________________  Coal Mine Hazard ______________________  Seismic Hazard _______________________  Habitat Protection ______________________  _____________________________________ Part 10 SOILS Soil Type _________________ _________________ _________________ _________________ Slopes _________________ _________________ _________________ _________________ Erosion Potential _________________ _________________ _________________ _________________  High Groundwater Table (within 5 feet)  Other ________________________________  Sole Source Aquifer  Seeps/Springs  Additional Sheets Attached 2016 Surface Water Design Manual 4/24/2016 2 East Lake Washington (per King County iMap) / May Creek Indianola Loamy Sand 5-15% x Zone 2 Aquifer Protection Area City of Renton's Flow Control Duration Standard: Forested site conditions KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE  Core 2 – Offsite Analysis_________________  Sensitive/Critical Areas__________________  SEPA________________________________  LID Infeasibility________________________  Other________________________________  _____________________________________ LIMITATION / SITE CONSTRAINT _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________  Additional Sheets Attached Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Threshold Discharge Area: (name or description) Core Requirements (all 8 apply): Discharge at Natural Location Number of Natural Discharge Locations: Offsite Analysis Level: 1 / 2 / 3 dated:__________________ Flow Control (include facility summary sheet) Level: 1 / 2 / 3 or Exemption Number ____________ Flow Control BMPs _______________________________ Conveyance System Spill containment located at: _________________________ Erosion and Sediment Control / Construction Stormwater Pollution Prevention CSWPP/CESCL/ESC Site Supervisor: _____________________ Contact Phone: _________________________ After Hours Phone: _________________________ Maintenance and Operation Responsibility (circle one): Private / Public If Private, Maintenance Log Required: Yes / No Financial Guarantees and Liability Provided: Yes / No Water Quality (include facility summary sheet) Type (circle one): Basic / Sens. Lake / Enhanced Basic / Bog or Exemption No. ______________________ Landscape Management Plan: Yes / No Special Requirements (as applicable): Area Specific Drainage Requirements Type: CDA / SDO / MDP / BP / LMP / Shared Fac. / None Name: ________________________ Floodplain/Floodway Delineation Type (circle one): Major / Minor / Exemption / None 100-year Base Flood Elevation (or range): ______________ Datum: Flood Protection Facilities Describe: 2016 Surface Water Design Manual 4/24/2016 3 Total Site 1 01/20/16 2 Infiltration Trench Surface Area Exemption KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Source Control (commercial / industrial land use) Describe land use: Describe any structural controls: 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 Collection  Dewatering Control  Dust Control  Flow Control  Protection of Flow Control BMP Facilities (existing and proposed)  Maintain BMPs / Manage Project 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, restore operation of Flow Control BMP Facilities as necessary  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 ________________ ________________ ________________ ________________ ________________ ________________  Vegetated Flowpath  Wetpool  Filtration  Oil Control  Spill Control  Flow Control BMPs  Other ________________ ________________ ________________ ________________ ________________ ________________ ________________ 2016 Surface Water Design Manual 4/24/2016 4 x x x x x x x x x x - N/A x x x x x Infiltration Trench x Stormfilter (Basic WQ) x Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section I, Page 3 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure I-2: Site Location Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section I, Page 4 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure I-3: Aerial Photograph PROJECT SITE Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section I, Page 5 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure I-4: Drainage Basin Map PROJECT SITE Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section I, Page 6 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure I-5: Soils Underlying soils were determined using the Natural Resources Conservation Service soil survey tool. The site contains Indianola loamy sand, 5 to 15%, corresponding to hydrologic soil group “A.” A geotechnical report with a recommended infiltration rate is also provided in Section VI. See attached pages. Soil Map—King County Area, Washington (Aberdeen Ave Subdivision) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/7/2016 Page 1 of 3526198052619905262000526201052620205262030526204052620505261990526200052620105262020526203052620405262050560910560920560930560940560950560960560970560980560990561000561010561020 560910 560920 560930 560940 560950 560960 560970 560980 560990 561000 561010 561020 47° 30' 32'' N 122° 11' 28'' W47° 30' 32'' N122° 11' 22'' W47° 30' 30'' N 122° 11' 28'' W47° 30' 30'' N 122° 11' 22'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 25 50 100 150Feet 0 5 10 20 30Meters Map Scale: 1:517 if printed on A landscape (11" x 8.5") sheet. Warning: Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: King County Area, Washington Survey Area Data: Version 11, Sep 14, 2015 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 31, 2013—Oct 6, 2013 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—King County Area, Washington (Aberdeen Ave Subdivision) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/7/2016 Page 2 of 3 Map Unit Legend King County Area, Washington (WA633) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI InC Indianola loamy sand, 5 to 15 percent slopes 0.8 100.0% Totals for Area of Interest 0.8 100.0% Soil Map—King County Area, Washington Aberdeen Ave Subdivision Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/7/2016 Page 3 of 3 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section II, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section II – Conditions and Requirements Summary TIR Section II Summary Core Requirements Adjustment Request The proposed project will comply with the 2017 Renton Surface Water Design Manual (RSWDM). The project is being submitted for a Full Drainage Review because it proposes to add and/or replace over 2,000 square feet of impervious area. The project must comply with all 9 Core Requirements and all 6 Special Requirements. Therefore, the following conditions are required as specified by the RSWDM. Core Requirements Core Requirement #1: Discharge at the Natural Location: Discharge will remain at the natural location and will flow from east to west. There is a public stormwater system in Aberdeen Ave NE that the site will connect into. Core Requirement #2: Offsite Analysis: Compliance with this requirement is indicated in Section III. Core Requirement #3: Flow Control: The site is within a Flow Control Duration Standard – Forested Site Conditions per the Flow Control Application Map of the 2017 RSWDM. However, the site is exempt from the flow facility requirement per Exception #2 of Section 1.2.3.1.B of the 2017 RSWDM. Core Requirement #4: Conveyance System: New pipe systems shall be designed with sufficient capacity to convey and contain (at minimum) the 25-year peak flow, assuming developed conditions for onsite tributary areas and existing conditions for any offsite tributary areas. Core Requirement #5: Erosion & Sediment Control: A Construction Stormwater Pollution Prevention Plan (CSWPPP) and narrative has been prepared. See Section VIII. Core Requirement #6: Maintenance & Operations: Maintenance requirements are addressed in Section X for the flow control BMP. Core Requirement #7: Financial Guarantees & Liabilities: The project may be required to execute to the City a construction bond prior to a permit and a maintenance bond prior to acceptance. Core Requirement #8: Water Quality: Less than 5,000 square feet of new plus replaced pollution generating impervious surface and less than ¾ acres of new pollution generating pervious surface are proposed. However, basic water quality treatment is required prior to infiltration for new plus replaced PGIS areas per Special Requirement #6: Aquifer Protection Area. A Contech StormFilter is proposed to meet this requirement. An adjustment request is included to omit the presettling requirement prior to the basic water quality treatment facility in this section. Core Requirement #9: Flow Control BMPs: This is discussed in Section IV. An infiltration trench is proposed to meet the flow control BMP requirement of this project. It was sized to meet the LID Performance Standard for the entire site. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section II, Page 2 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Special Requirements Special Requirement #1: Other Adopted Requirements: Not applicable. Special Requirement #2: Flood Hazard Area Delineation: Not applicable. Special Requirement #3: Flood Protection Facilities: Not applicable. Special Requirement #4: Source Control: Permanent and temporary source Controls are discussed in Section 8 of this report. Special Requirement #5: Oil Control: Not applicable. Special Requirement #6: Aquifer Protection Area: The site is in Zone 2 of the Aquifer Protection Area. The project proposes an infiltration trench to meet Core Requirement #9 and will therefore require water quality treatment prior to infiltration as specified in Core Requirement #8 and Special Requirement #6 OR demonstrate that the soil beneath the facility has properties that reduce the risk of groundwater contamination from typical stormwater runoff. This is addressed in Section IV. 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com May 11, 2017 City of Renton 1055 South Grady Way Renton, WA 98055 Project Name: Aberdeen Ave Short Plat Project Address: 1824 Aberdeen Ave NE Subject: Standard Adjustment to 2017 RSWDM We are requesting a drainage adjustment from Chapter 6: Water Quality Design of the 2017 Renton Surface Water Design Manual (RSWDM). The project is subject to the basic water quality treatment requirement because it is located within Zone 2 of the Critical Aquifer Recharge Area and proposes to use an infiltration trench to meet Core Requirement #9: Flow Control BMPs. A StormFilter by Contech is proposed within the shared driveway to treat all pollution-generating impervious areas prior to runoff entering the infiltration trench. Per Basic WQ Option 8 – Proprietary Facilities of Section 6.1.1, a “presettling cell or facility is required for both cartridge filters and non-cartridge media filters.” We request to omit this requirement for a presettling cell or facility. The project proposes a maximum of 4,100 sf of pollution-generating impervious surfaces—less than the 5,000 sf threshold that usually triggers water quality treatment per Core Requirement #8. The StormFilter by Contech also has a design that allows for some presettling. Please see the attached detail. We respectfully request an adjustment for Chapter 6 of the RSWDM. We would welcome an opportunity to meet with you to address any questions or concerns you may have. Attachments 1. Contech StormFilter Detail Sincerely, CG Engineering Greg Guillen, PE, SE Principal Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section III, Page 3 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section III – Off Site Analysis TIR Section III Summary Narrative The site currently contains one single-family home with a detached garage and a detached accessory building. The existing structures will be demolished in order to add an access and utility tract, and a house on the back lot. The slope across the lot is downstream from east to west at an average of 4%. Adjacent lots contain single family residences. Task 1: Study Area Definition and Maps The study area is defined as the project site and the area one mile downstream (minimum flow path distance) from the proposed discharge location for the purposes of Task 2, and is defined as the project site and a minimum of one-quarter mile downstream from the proposed discharge location for the purposes of Tasks 3, 4, and 5. The drainage path is shown in Figure III-1 for a minimum of ¼ mile downstream from the City’s GIS map. Currently, surface runoff enters the 18” CPEP public storm main along Aberdeen Ave NE, flows north along Aberdeen Ave NE, crosses through Kennydale Lions Park, and outfalls to May Creek near Kennewick Pl NE and I-405. The site is within the East Lake Washington/May Creek drainage basin. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section III, Page 4 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure III-1 Downstream drainage path. Task 2: Resource Review Drainage and water quality problems and complaints were investigated using the King County iMap website. None were found within the range of the required downstream analysis. The site does not appear to contain nor is adjacent to any environmentally sensitive areas. Task 3: Field Inspection A site visit was done the morning of 01/20/2016 and the flow path downstream of the site was observed. There did not appear to be any existing drainage issues. There is an 18” public storm main on the western frontage of Aberdeen Ave NE. PROJECT SITE Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section III, Page 5 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure III-2 View of Aberdeen Ave NE looking south. Figure III-3 View of site (on left) looking east. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section III, Page 6 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Figure III-4 View of Aberdeen Ave NE looking north. Figure III-5 View from back of site looking west. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section III, Page 7 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Task 4: Drainage System Description and Problem Descriptions No drainage problems are expected. The existing conveyances adjacent to the site include an 18” public storm main on the western frontage of Aberdeen Ave NE. Site runoff is expected to flow in the existing condition from east to west and connect into this system. Task 5: Mitigation of Existing or Potential Problems No existing drainage problems were discovered. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section IV – Flow Control and Water Quality Facility Analysis and Design TIR Section IV Summary: Narrative PART A: Existing Site Hydrology PART B: Developed Site Hydrology PART C: Performance Standards PART D: Flow Control System PART E: Water Quality System StormFilter Sizing Sheet WWHM2012 Report PART A: EXISTING SITE HYDROLOGY The 2012 Western Washington Hydrology Model (WWHM2012) was used to model flow control. Per the City of Renton’s Flow Control Application Map (Reference 11-A in the RSWDM), the site is within the Flow Control Duration Standard (Forested Condition). The predeveloped land coverage is as follows: Pervious Areas Forest, Flat, A/B: 16,161 sf (0.370 ac) Total: 16,161 sf (0.370 ac) PART B: DEVELOPED SITE HYDROLOGY In the proposed condition, the existing lot will be subdivided into 2 lots and existing structures will be demolished. Impervious areas were assumed for the proposed lots according to Section 3.2 of the 2017 RSWDM since Lot 1 and Lot 2 will be developed in the future. Per Section 3.2, the assumed impervious coverage “shall not be less than 4,000 sf per lot or the maximum impervious coverage permitted by code Table 3.2.2.C, whichever is less.” The maximum impervious coverage allowed per code for the zoning (R-8) is 65%, or 3,689 sf and 5,135 sf for Lot 1 and Lot 2, respectively. The assumed impervious coverage shall be 65% and the maximum building coverage shall be 50% for the purposes of this hydrology model. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 2 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com The assumed developed lot coverage is as follows: Lot 1 Developed Lot Coverage Lawn, Flat, A/B: 1,988 sf (0.045 ac) Roof, Flat: 2,838 sf (0.065 ac) Driveway/Walkways, Flat: 851 sf (0.020 ac) Total: 5,677 sf (0.130 ac) Lot 2 Developed Lot Coverage Lawn, Flat, A/B: 2,768 sf (0.063 ac) Roof, Flat: 3,951 sf (0.091 ac) Driveway/Walkways, Flat, A/B: 1,184 sf (0.027 ac) Total: 7,903 sf (0.181 ac) Tract Developed Lot Coverage Pasture, Flat, A/B: 516 sf (0.012 ac) Driveway, Flat, A/B: 2,065 sf (0.047 ac) Total: 2,581 sf (0.059 ac) WWHM2012 was used to model the site to meet the onsite LID Performance Standard per Core Requirement #9. All impervious areas from the entire site and the lawn area from Lot 2 will be routed to the proposed infiltration trench. The lawn area from Lot 1 and the landscape area in the driveway tract will disperse off the site. The landscape area from the driveway tract is modeled as “pasture” because areas meeting the soil amendment requirements per section C.2.13 of the 2017 RSWDM may be modeled as “pasture” rather than “lawn.” The proposed Flow Control BMP is an Infiltration Trench per Section 5.2 of the 2017 RSWDM. An infiltration design rate of 7.35 in/hr was determined for the site (see Section VI for the geotechnical report). The trench was sized to be 80’x5’x2’ deep and will be sited in the driveway tract. PART C: PERFORMANCE STANDARDS 1. Area-Specific Flow Control Facility standard: The site is within the City of Renton’s Flow Control Duration Standard (Forested Conditions). 2. Flow Control BMPs: Flow Control BMP Implementation requirements were determined from Section 1.2.9.3.1 “Small Subdivision and Urban Subdivision Projects BMP Requirements.” BMPs for plat infrastructure improvements (driveway tract) were evaluated per Section 1.2.9.3.2 “Small Road Improvement and Urban Road Improvement Project BMP Requirements.” BMPs for the future development of the two individual lots were evaluated per Section 1.2.9.2.1 “Small Lot BMP Requirements.” 3. Conveyance System Capacity Standards: New pipe systems shall be designed with sufficient capacity to convey and contain (at minimum) the 25-year peak flow, assuming developed conditions for onsite tributary areas and existing conditions for any offsite tributary areas. 4. Water Quality Standard: Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 3 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Stormwater from pollution-generating impervious areas will be treated to meet Basic Water Quality prior to infiltration because the site is located in a Zone 2 Aquifer Protection Area. PART D: FLOW CONTROL SYSTEM An infiltration trench is proposed to meet the LID Performance Standard per Core Requirement #9: On- Site BMPs. The trench will be 80’ x 5’ x 2’ deep and will be sited within the access/utility tract. The design infiltration rate used was 7.35 in/hr per the geotechnical report found in Section VI. The project is exempt from the facility requirement of Core Requirement #3: Flow Control per Exception #2 of Section 1.2.3.1.B of the 2017 RSWDM because the 100-year peak flow is no more than 0.15 cfs (when modeled using 15-minute time steps). Please see the WWHM summary. The model includes the infiltration trench. PART E: WATER QUALITY SYSTEM A water quality system meeting Basic Water Quality was sized to treat runoff from pollution generating impervious surfaces prior to infiltration because the site is in a Zone 2 Aquifer Protection Area. The drainage area to the water quality facility is assumed to be the driveway areas from the entire site and the lawn area from Lot 2. A sizing sheet for the Stormfilter by Contech is provided. An adjustment to omit presettling requirements for the StormFilter facility is included in Section II. Size and Cost Estimate 11835 NE Glenn Widing Dr., Portland OR 97220 Toll-free: 800.548.4667 Fax: 800.561.1271 ©2012 Contech Engineered Solutions LLC www.conteches.com Page 1 of 1 TS-P027 Prepared by Stephanie Jacobsen on May 12, 2017 Aberdeen Ave NE Short Plat– Stormwater Treatment System Renton, WA Information provided: • Total contributing area = 0.157ac • Impervious area = 0.094ac • Water quality flow = 0.0086cfs (offline) • Peak hydraulic flow rate = 0.079cfs • Presiding agency = City of Renton, WA Assumptions: • Media = ZPG cartridges • Cartridge flow rate = 7.5 gpm • Drop required from inlet to outlet = 2.3’ minimum Size and cost estimates: The StormFilter is a flow-based system, and is therefore sized by calculating the peak water quality flow rate associated with the design storm. The water quality flow rate was calculated by the consulting engineer using WWHM and was provided to Contech Engineered Solutions LLC for the purposes of developing this estimate. The StormFilter for this site was sized based on a water quality flow rate of 0.0086cfs. To accommodate this flow rate, Contech Engineered Solutions recommends using a StormFilter catch basin with 1 cartridge (see attached detail). The estimated cost of this system is $5,500, complete and delivered to the job site. This estimate assumes that the vault is 2.3 feet deep. The final system cost will depend on the actual depth of the units and whether extras like doors rather than castings are specified. The contractor is responsible for setting the StormFilter and all external plumbing. Typically the precast StormFilters have internal bypass capacities of 1.8 cfs. If the peak discharge off the site is expected to exceed this rate, we recommend placing a high-flow bypass upstream of the StormFilter system. Contech Engineered Solutions could provide our high-flow bypass, the StormGate, which provides a combination weir-orifice control structure to limit the flow to the StormFilter. The estimated cost of this structure is $4,000. The final cost would depend on the actual depth and size of the unit. Project Name:Aberdeen Ave NE Short Plat Site Designation:Date:5/12/17 County or Independent City:Renton Design Engineer:SKJ State:WA Flow Based Data: Peak Design Flow (cfs) Water Quality Flow (cfs) Annual Rainfall (inches) Total Drainage Area, A (ac) Post Development Impervious Area, AI (ac) Pervious Area, AP (ac) % Impervious Runoff Coefficient, Rc TSS Removal By Pretreatment Agency Required TSS % Removal Required TSS Removal Efficiency of Filter Percent Runoff Capture Mean Annual Runoff, Vt (ft3) Event Mean Concentration of Pollutant, EMC (mg/L) Annual Mass Load, Mtotal (lbs) Flow Based Filter Sizing: Mass to be Captured by System (lbs) Filter Type Structure Type Cartridge Height Media Type Cartridge Flow Rate, gpm/sf Allowable Load Per Cartridge (lbs) Cartridges Required Recommended Model TSS Treatment Capacity (lbs) Maximum Water Quality Flow 36 0.16 0.09 0.01 StormFilter Catchbasin (Steel) 90% 10,873 12.21 1 SFCB1 1.00 gpm/sf ZPG 0.08 50% 60% 0.06 60% 0.95 0.25 0.59 80% 40.70 60 36.00 0.02 cfs 18'' 36 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 4 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com WWHM2012 PROJECT REPORT ___________________________________________________________________ Project Name: Aberdeen Ave 05.09.17 Site Name: Aberdeen Ave Short Plat Site Address: 1824 Aberdeen Ave NE City : Renton Report Date: 5/9/2017 Gage : Seatac Data Start : 1948/10/01 Data End : 2009/09/30 Precip Scale: 1.00 Version : 2014/01/22 ___________________________________________________________________ PREDEVELOPED LAND USE Name : Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Forest, Flat .37 Pervious Total 0.37 Impervious Land Use Acres Impervious Total 0 Basin Total 0.37 ___________________________________________________________________ Element Flows To: Surface Interflow Groundwater ___________________________________________________________________ MITIGATED LAND USE Name : Gravel Trench Areas Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Flat .063 Pervious Total 0.063 Impervious Land Use Acres Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 5 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com ROOF TOPS FLAT 0.156 DRIVEWAYS FLAT 0.094 Impervious Total 0.25 Basin Total 0.313 ___________________________________________________________________ Element Flows To: Surface Interflow Groundwater Gravel Trench Bed 1 Gravel Trench Bed 1 ___________________________________________________________________ Name : Gravel Trench Bed 1 Bottom Length: 80.00 ft. Bottom Width: 5.00 ft. Trench bottom slope 1: 0.0001 To 1 Trench Left side slope 0: 0 To 1 Trench right side slope 2: 0 To 1 Material thickness of first layer: 2 Pour Space of material for first layer: 0.3 Material thickness of second layer: 0 Pour Space of material for second layer: 0 Material thickness of third layer: 0 Pour Space of material for third layer: 0 Infiltration On Infiltration rate: 7.35 Infiltration safety factor: 1 Total Volume Infiltrated (ac-ft): 38.746 Total Volume Through Riser (ac-ft): 0.033 Total Volume Through Facility (ac-ft): 38.779 Percent Infiltrated: 99.91 Discharge Structure Riser Height: 1.9 ft. Riser Diameter: 6 in. Element Flows To: Outlet 1 Outlet 2 ___________________________________________________________________ Gravel Trench Bed Hydraulic Table Stage(ft) Area(ac) Volume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.009 0.000 0.000 0.000 0.0222 0.009 0.000 0.000 0.068 0.0444 0.009 0.000 0.000 0.068 0.0667 0.009 0.000 0.000 0.068 0.0889 0.009 0.000 0.000 0.068 0.1111 0.009 0.000 0.000 0.068 0.1333 0.009 0.000 0.000 0.068 0.1556 0.009 0.000 0.000 0.068 0.1778 0.009 0.000 0.000 0.068 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 6 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com 0.2000 0.009 0.000 0.000 0.068 0.2222 0.009 0.000 0.000 0.068 0.2444 0.009 0.000 0.000 0.068 0.2667 0.009 0.000 0.000 0.068 0.2889 0.009 0.000 0.000 0.068 0.3111 0.009 0.000 0.000 0.068 0.3333 0.009 0.000 0.000 0.068 0.3556 0.009 0.001 0.000 0.068 0.3778 0.009 0.001 0.000 0.068 0.4000 0.009 0.001 0.000 0.068 0.4222 0.009 0.001 0.000 0.068 0.4444 0.009 0.001 0.000 0.068 0.4667 0.009 0.001 0.000 0.068 0.4889 0.009 0.001 0.000 0.068 0.5111 0.009 0.001 0.000 0.068 0.5333 0.009 0.001 0.000 0.068 0.5556 0.009 0.001 0.000 0.068 0.5778 0.009 0.001 0.000 0.068 0.6000 0.009 0.001 0.000 0.068 0.6222 0.009 0.001 0.000 0.068 0.6444 0.009 0.001 0.000 0.068 0.6667 0.009 0.001 0.000 0.068 0.6889 0.009 0.001 0.000 0.068 0.7111 0.009 0.002 0.000 0.068 0.7333 0.009 0.002 0.000 0.068 0.7556 0.009 0.002 0.000 0.068 0.7778 0.009 0.002 0.000 0.068 0.8000 0.009 0.002 0.000 0.068 0.8222 0.009 0.002 0.000 0.068 0.8444 0.009 0.002 0.000 0.068 0.8667 0.009 0.002 0.000 0.068 0.8889 0.009 0.002 0.000 0.068 0.9111 0.009 0.002 0.000 0.068 0.9333 0.009 0.002 0.000 0.068 0.9556 0.009 0.002 0.000 0.068 0.9778 0.009 0.002 0.000 0.068 1.0000 0.009 0.002 0.000 0.068 1.0222 0.009 0.002 0.000 0.068 1.0444 0.009 0.002 0.000 0.068 1.0667 0.009 0.002 0.000 0.068 1.0889 0.009 0.003 0.000 0.068 1.1111 0.009 0.003 0.000 0.068 1.1333 0.009 0.003 0.000 0.068 1.1556 0.009 0.003 0.000 0.068 1.1778 0.009 0.003 0.000 0.068 1.2000 0.009 0.003 0.000 0.068 1.2222 0.009 0.003 0.000 0.068 1.2444 0.009 0.003 0.000 0.068 1.2667 0.009 0.003 0.000 0.068 1.2889 0.009 0.003 0.000 0.068 1.3111 0.009 0.003 0.000 0.068 1.3333 0.009 0.003 0.000 0.068 1.3556 0.009 0.003 0.000 0.068 1.3778 0.009 0.003 0.000 0.068 1.4000 0.009 0.003 0.000 0.068 1.4222 0.009 0.003 0.000 0.068 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 7 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com 1.4444 0.009 0.004 0.000 0.068 1.4667 0.009 0.004 0.000 0.068 1.4889 0.009 0.004 0.000 0.068 1.5111 0.009 0.004 0.000 0.068 1.5333 0.009 0.004 0.000 0.068 1.5556 0.009 0.004 0.000 0.068 1.5778 0.009 0.004 0.000 0.068 1.6000 0.009 0.004 0.000 0.068 1.6222 0.009 0.004 0.000 0.068 1.6444 0.009 0.004 0.000 0.068 1.6667 0.009 0.004 0.000 0.068 1.6889 0.009 0.004 0.000 0.068 1.7111 0.009 0.004 0.000 0.068 1.7333 0.009 0.004 0.000 0.068 1.7556 0.009 0.004 0.000 0.068 1.7778 0.009 0.004 0.000 0.068 1.8000 0.009 0.005 0.000 0.068 1.8222 0.009 0.005 0.000 0.068 1.8444 0.009 0.005 0.000 0.068 1.8667 0.009 0.005 0.000 0.068 1.8889 0.009 0.005 0.000 0.068 1.9111 0.009 0.005 0.005 0.068 1.9333 0.009 0.005 0.029 0.068 1.9556 0.009 0.005 0.063 0.068 1.9778 0.009 0.005 0.105 0.068 2.0000 0.009 0.005 0.154 0.068 ___________________________________________________________________ Name : Runoff Areas Bypass: Yes GroundWater: No Pervious Land Use Acres A B, Lawn, Flat .045 A B, Pasture, Flat .012 Pervious Total 0.057 Impervious Land Use Acres Impervious Total 0 Basin Total 0.057 ___________________________________________________________________ Element Flows To: Surface Interflow Groundwater ___________________________________________________________________ LID Duration ___________________________________________________________________ Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 8 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.37 Total Impervious Area:0 ___________________________________________________________________ Mitigated Landuse Totals for POC #1 Total Pervious Area:0.12 Total Impervious Area:0.25 ___________________________________________________________________ Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.000314 5 year 0.000475 10 year 0.000606 25 year 0.000803 50 year 0.000975 100 year 0.00117 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.000375 5 year 0.002345 10 year 0.006899 25 year 0.023968 50 year 0.056501 100 year 0.126696 ___________________________________________________________________ LID Duration Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.000 0.000 1950 0.001 0.004 1951 0.001 0.001 1952 0.000 0.000 1953 0.000 0.000 1954 0.000 0.001 1955 0.000 0.000 1956 0.000 0.002 1957 0.000 0.000 1958 0.000 0.000 1959 0.000 0.000 1960 0.000 0.001 1961 0.000 0.001 1962 0.000 0.000 1963 0.000 0.000 1964 0.000 0.001 1965 0.000 0.001 1966 0.000 0.000 1967 0.000 0.003 1968 0.000 0.001 1969 0.000 0.000 1970 0.000 0.000 1971 0.000 0.000 1972 0.002 0.003 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 9 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com 1973 0.000 0.000 1974 0.000 0.000 1975 0.000 0.001 1976 0.000 0.001 1977 0.000 0.000 1978 0.000 0.000 1979 0.000 0.000 1980 0.000 0.000 1981 0.000 0.000 1982 0.000 0.014 1983 0.000 0.000 1984 0.000 0.000 1985 0.000 0.000 1986 0.000 0.000 1987 0.000 0.001 1988 0.000 0.000 1989 0.000 0.000 1990 0.000 0.050 1991 0.000 0.011 1992 0.000 0.000 1993 0.000 0.000 1994 0.000 0.000 1995 0.000 0.001 1996 0.002 0.004 1997 0.000 0.001 1998 0.000 0.000 1999 0.000 0.036 2000 0.000 0.000 2001 0.000 0.000 2002 0.000 0.000 2003 0.000 0.000 2004 0.000 0.083 2005 0.000 0.000 2006 0.000 0.001 2007 0.003 0.042 2008 0.000 0.060 2009 0.000 0.001 ___________________________________________________________________ LID Duration Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0031 0.0833 2 0.0021 0.0596 3 0.0015 0.0497 4 0.0006 0.0419 5 0.0006 0.0362 6 0.0005 0.0145 7 0.0005 0.0113 8 0.0003 0.0042 9 0.0003 0.0041 10 0.0003 0.0033 11 0.0003 0.0029 12 0.0003 0.0018 13 0.0003 0.0014 14 0.0003 0.0011 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 10 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com 15 0.0003 0.0011 16 0.0003 0.0011 17 0.0003 0.0010 18 0.0003 0.0010 19 0.0003 0.0009 20 0.0003 0.0009 21 0.0003 0.0008 22 0.0003 0.0007 23 0.0003 0.0006 24 0.0003 0.0006 25 0.0003 0.0006 26 0.0003 0.0005 27 0.0003 0.0005 28 0.0003 0.0004 29 0.0003 0.0004 30 0.0003 0.0003 31 0.0003 0.0003 32 0.0003 0.0003 33 0.0003 0.0003 34 0.0003 0.0003 35 0.0003 0.0002 36 0.0003 0.0002 37 0.0003 0.0002 38 0.0003 0.0002 39 0.0003 0.0002 40 0.0003 0.0002 41 0.0003 0.0002 42 0.0003 0.0002 43 0.0003 0.0001 44 0.0003 0.0001 45 0.0003 0.0001 46 0.0003 0.0001 47 0.0003 0.0001 48 0.0003 0.0001 49 0.0003 0.0001 50 0.0003 0.0001 51 0.0003 0.0001 52 0.0003 0.0001 53 0.0003 0.0000 54 0.0003 0.0000 55 0.0003 0.0000 56 0.0003 0.0000 57 0.0003 0.0000 58 0.0003 0.0000 59 0.0002 0.0000 60 0.0002 0.0000 61 0.0002 0.0000 ___________________________________________________________________ LID Duration POC #1 The Facility PASSED The Facility PASSED. Flow(cfs) Predev Mit Percentage Pass/Fail Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 11 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com 0.0000 22202 9060 40 Pass 0.0000 21496 8237 38 Pass 0.0000 20867 7366 35 Pass 0.0000 19868 6023 30 Pass 0.0000 19363 5409 27 Pass 0.0000 18749 4857 25 Pass 0.0000 17825 3816 21 Pass 0.0000 17396 3349 19 Pass 0.0000 17008 2898 17 Pass 0.0000 16262 2080 12 Pass 0.0000 15888 1835 11 Pass 0.0000 15571 1642 10 Pass 0.0000 14966 1452 9 Pass 0.0000 14645 1422 9 Pass 0.0000 14345 1406 9 Pass 0.0000 13734 1356 9 Pass 0.0000 13483 1334 9 Pass 0.0000 13208 1317 9 Pass 0.0000 12714 1285 10 Pass 0.0001 12536 1270 10 Pass 0.0001 12316 1254 10 Pass 0.0001 11920 1229 10 Pass 0.0001 11683 1217 10 Pass 0.0001 11494 1199 10 Pass 0.0001 11077 1171 10 Pass 0.0001 10891 1154 10 Pass 0.0001 10697 1135 10 Pass 0.0001 10230 1097 10 Pass 0.0001 10072 1093 10 Pass 0.0001 9942 1081 10 Pass 0.0001 9683 1056 10 Pass 0.0001 9546 1044 10 Pass 0.0001 9396 1033 10 Pass 0.0001 9124 1014 11 Pass 0.0001 8992 1007 11 Pass 0.0001 8846 997 11 Pass 0.0001 8579 977 11 Pass 0.0001 8466 968 11 Pass 0.0001 8359 961 11 Pass 0.0001 8132 938 11 Pass 0.0001 8029 931 11 Pass 0.0001 7942 926 11 Pass 0.0001 7760 910 11 Pass 0.0001 7649 899 11 Pass 0.0001 7533 886 11 Pass 0.0001 7343 878 11 Pass 0.0001 7268 867 11 Pass 0.0001 7157 855 11 Pass 0.0001 6930 839 12 Pass 0.0001 6857 832 12 Pass 0.0001 6772 827 12 Pass 0.0001 6592 817 12 Pass 0.0001 6513 811 12 Pass 0.0001 6449 806 12 Pass 0.0001 6288 797 12 Pass 0.0001 6228 793 12 Pass Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 12 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com 0.0001 6141 788 12 Pass 0.0001 6006 778 12 Pass 0.0001 5908 773 13 Pass 0.0001 5822 769 13 Pass 0.0001 5636 761 13 Pass 0.0001 5557 753 13 Pass 0.0001 5482 743 13 Pass 0.0001 5341 726 13 Pass 0.0001 5255 721 13 Pass 0.0001 5191 715 13 Pass 0.0001 5082 704 13 Pass 0.0001 5031 698 13 Pass 0.0001 4981 694 13 Pass 0.0001 4868 690 14 Pass 0.0001 4823 684 14 Pass 0.0001 4757 683 14 Pass 0.0001 4644 675 14 Pass 0.0001 4577 670 14 Pass 0.0001 4517 665 14 Pass 0.0001 4391 654 14 Pass 0.0001 4331 652 15 Pass 0.0001 4250 650 15 Pass 0.0001 4132 644 15 Pass 0.0001 4083 641 15 Pass 0.0001 4036 636 15 Pass 0.0001 3944 631 15 Pass 0.0001 3910 625 15 Pass 0.0001 3861 622 16 Pass 0.0001 3764 614 16 Pass 0.0001 3724 612 16 Pass 0.0001 3687 607 16 Pass 0.0001 3617 602 16 Pass 0.0001 3580 598 16 Pass 0.0001 3544 597 16 Pass 0.0001 3454 592 17 Pass 0.0001 3420 591 17 Pass 0.0001 3384 587 17 Pass 0.0001 3313 583 17 Pass 0.0002 3275 580 17 Pass 0.0002 3225 575 17 Pass 0.0002 3157 571 18 Pass 0.0002 3123 569 18 Pass 0.0002 3095 567 18 Pass 0.0002 3033 560 18 Pass ___________________________________________________________________ LID Report LID Technique Used for Total Volumn Volumn Infiltration Cumulative Percent Water Quality Percent Comment Treatment? Needs Through Volumn Volumn Volumn Water Quality Treatment Facility (ac-ft) Infiltration Infiltrated Treated (ac-ft) (ac-ft) Credit Gravel Trench Bed 1 POC N 35.79 N 98.51 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IV, Page 13 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Total Volume Infiltrated 35.79 0.00 0.00 98.51 0.00 0% No Treat. Credit Compliance with LID Standard 8 Duration Analysis Result = Passed ___________________________________________________________________ Perlnd and Implnd Changes No changes have been made. ___________________________________________________________________ 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. 2005-2013; All Rights Reserved. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section V, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section V – Conveyance System Analysis and Design TIR Section V Summary: Narrative Per Core Requirement #4, new pipe systems shall be designed with sufficient capacity to convey and contain the 25-year peak flow. Conveyance capacity shall be demonstrated using the methods in Chapter 4 of the KCSWDM. Verification of capacity and performance must be provided for each element of the conveyance system. The analysis must show design velocities and flows for all drainage facilities within the development, as well as those offsite that are affected by the development. The conveyance system will consist of 6” PVC pipes for roof and driveway runoff and a 12” ductile iron pipe as the overflow from the infiltration trench. The 6” PVC pipes will therefore be verified for capacity. The 25-year peak flow for the inflow to the infiltration trench was calculated per WWHM and found to be 0.16 cfs. The conveyance capacity of a 6” PVC pipe with a minimum 1% slope is 0.56 cfs. Therefore, a 6” PVC is sufficient for the design event. See the conveyance capacity calculation on the following page. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section V, Page 2 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section VI, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section VI – Special Reports and Studies TIR Section VI Summary: Narrative Please refer to the following reports submitted with the application: 1. Geotechnical Engineering Evaluation by Nelson Geotechnical Associates, Inc., dated October 17, 2016. 2. Supplemental Memorandum to the Geotechnical Engineering Evaluation by Nelson Geotechnical Associates, Inc., dated February 10, 2017. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section VII, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section VII – Other Permits TIR Section VII Narrative Other permits are not anticipated that would contain more restrictive drainage plan requirements. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section VIII, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section VIII – CSWPPP Analysis and Design TIR Section VIII Summary Narrative This section of the TIR is to provide a summary of erosion controls and source controls for the site. The project proposes to subdivide a single 16,161 sf parcel in the R-8 zone into 2 individual single-family lots. The site currently contains one single-family home with a detached garage and a detached accessory building. The existing structures will be demolished in order to add an access and utility tract, and a house on the back lot. The project will add more than 2,000 sf of impervious surfaces and so must meet the Full Drainage requirements from the 2016 King County Surface Water Design Manual as amended by the City of Renton. The project will construct the necessary stormwater improvements for the access/utility tract and lots, but development of Lots 1 and 2 will occur at a later date. ESC and SWPPS measures were chosen per Section D.2 the 2016 King County Surface Water Design Manual. Less than 1 acre of land will be disturbed and therefore the Department of Ecology SWPPP and Construction Stormwater General Permit is not required. ESC Measures The following ESC measures are suggested for each category below: 1. Clearing Limits: To protect adjacent properties, existing trees, and to reduce the area of soil exposed to construction, the limits of construction will be clearly marked before land-disturbing activities begin. The BMPs relevant to marking the clearing limits that will be applied for this project include:  High Visibility Plastic or Metal Fence 2. Cover Measures Exposed and unworked soils shall be stabilized with the application of effective BMPs to prevent erosion throughout the life of the project. Temporary cover shall be installed if an area is to remain unworked for more than seven days during the dry season (May 1 to September 30) or for more than two consecutive working days during the wet season (October 1 to April 30). The suggested BMPs for soil stabilization that shall be used on this project include:  Temporary & Permanent Seeding  Mulching  Nets & Blankets  Plastic Covering 3. Perimeter Protection All stormwater runoff from disturbed areas shall pass through an appropriate sediment removal BMP before leaving the construction site or prior to being discharged. Silt fences will be installed on Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section VIII, Page 2 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com the downstream sides of the site. The specific BMPs to be used for controlling sediment on this project include:  Silt Fence 4. Traffic Area Stabilization A stabilized construction entrance will be established to the west side of the site using the existing gravel driveway.  Stabilized Construction Entrance 5. Sediment Retention The site is small enough that perimeter protection is expected to be adequate for sediment retention onsite. 6. Surface Water Collection The site is small enough that perimeter protection is expected to be adequate for sediment retention onsite. 7. Dewatering Control Dewatering is not anticipated. 8. Dust Control Dust control will be used to minimize wind transport of soil. Water and/or other dust control measures may be used upon approval by the County.  Dust Control 9. Flow Control Increases in the 2-year and 10-year runoff event is expected to be small due to the size of the site. Flow control measures are not proposed. 10. Protect Existing and Proposed Flow Control BMPs Stormwater facilities and on-site BMPs areas are identified on the Temporary Erosion Control Plan. These areas shall be protected from sedimentation and soil compaction that would adversely affect infiltration. 11. Maintain BMPs BMPs will be maintained and repaired as necessary throughout construction. The CSWPP supervisor shall review the site for ESC and SWPPS at least weekly and within 24 hours of significant storms. All temporary erosion and sediment control BMPs will be removed within 30 days after achieving final site stabilization. 12. Manage the Project Projects shall assign a qualified CSWPPP supervisor to be the primary contact for ESC and SWPPP issues and reporting. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section VIII, Page 3 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com SWPPS Measures The following SWPPS measures are expected for the site. 1. Concrete Handling Management practices per Section D.2.2.1 “Concrete Handling” shall be utilized any time concrete is used to minimize and eliminate concrete, concrete process water, and concrete slurry runoff. 2. Concrete Washout Area Prevent or reduce the discharge of pollutants to stormwater from concrete waste by conducting washout off-site, or performing on-site washout in a designated area to prevent pollutants from entering surface waters or ground water. 3. Sawcutting and Surfacing Pollution Prevention Utilize these management practices anytime sawcutting or surfacing operations take place. Sawcutting and surfacing operations include, but are not limited to, sawing, coring, grinding, roughening, hydrodemolition, bridge and road surfacing. 4. Material Delivery, Storage and Containment These procedures are suitable for use at all construction sites with delivery and storage of the following materials: Petroleum products such as fuel, oil and grease; Soil stabilizers and binders (e.g. Polyacrylamide); Fertilizers, pesticides and herbicides; Detergents; Asphalt and concrete compounds; Hazardous chemicals such as acids, lime, adhesives, paints, solvents and curing compounds; Any other material that may be detrimental if released to the environment. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section IX, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section IX – Bond Quantities, Facility Summaries, and Declaration of Covenant TIR Section IX Summary: Narrative A Declaration of Covenant for the flow control BMP and a Bond Quantity Worksheet are provided. There are no flow control facilities proposed. RECORDING REQUESTED BY AND WHEN RECORDED MAIL TO: CITY CLERK’S OFFICE CITY OF RENTON 1055 SOUTH GRADY WAY RENTON, WA 98057 DECLARATION OF COVENANT FOR MAINTENANCE AND INSPECTION OF FLOW CONTROL BMPS Grantor: Grantee: City of Renton Legal Description: Additional Legal(s) on: Assessor's Tax Parcel ID#: IN CONSIDERATION of the approved City of Renton(check one of the following) residential building permit, commercial building permit, clearing and grading permit, subdivision permit, or short subdivision permit for Application File No. LUA/SWP ____________________ relating to the real property ("Property") described above, the Grantor(s), the owner(s) in fee of that Property, hereby x covenants(covenant) with City or Renton, a political subdivision of the state of Washington, that he/she(they) will observe, consent to, and abide by the conditions and obligations set forth and described in Paragraphs 1 through 8 below with regard to the Property. Grantor(s) hereby grants(grant), covenants(covenant), and agrees(agree) as follows: 1. Grantor(s) or his/her(their) successors in interest and assigns ("Owners") shall retain, uphold, and protect the stormwater management devices, features, pathways, limits, and restrictions, known as flow control best management practices ("BMPs"), shown on the approved Flow Control BMP Site Plan for the Property attached hereto and incorporated herein as Exhibit A. 2. The Owners shall at their own cost, operate, maintain, and keep in good repair, the Property's BMPs as described in the approved Design and Maintenance Details for each BMP attached hereto and incorporated herein as Exhibit B. 3. City or Renton shall provide at least 30 days written notice to the Owners that entry on the Property is planned for the inspection of the BMPs. After the 30 days, the Owners shall allow the City of Renton to enter for the sole purpose of inspecting the BMPs. In lieu of inspection by the City, the Owners may elect to engage a licensed civil engineer registered in the state of Washington who has expertise in drainage to inspect the BMPs and provide a written report describing their condition. If the engineer option is chosen, the Owners shall provide written notice to the City of Renton within fifteen days of receiving the City's notice of inspection. Within 30 days of giving this notice, the Owners, or the engineer on behalf of the Owners, shall provide the engineer's report to the City of Renton. If the report is not provided in a timely manner as specified above, the City of Renton may inspect the BMPs without further notice. 4. If the City determines from its inspection, or from an engineer's report provided in accordance with Paragraph 3, that maintenance, repair, restoration, and/or mitigation work is required for the BMPs, The City shall notify the Owners of the specific maintenance, repair, restoration, and/or mitigation work (Work) required under RMC 4-6-030. The City shall also set a reasonable deadline for completing the Work or providing an engineer's report that verifies completion of the Work. After the deadline has passed, the Owners shall allow the City access to re-inspect the BMPs unless an engineer's report has been provided verifying completion of the Work. If the work is not completed properly within the time frame set by the City, the City may initiate an enforcement action. Failure to properly maintain the BMPs is a violation of RMC 4-6-030 and may subject the Owners to enforcement under the RMC 1-3, including fines and penalties. 5. Apart from performing routine landscape maintenance, the Owners are hereby required to obtain written approval from the City or Renton before performing any alterations or modifications to the BMPs. 6. Any notice or approval required to be given by one party to the other under the provisions of this Declaration of Covenant shall be effective upon personal delivery to the other party, or after three (3) days from the date that the notice or approval is mailed with delivery confirmation to the current address on record with each Party. The parties shall notify each other of any change to their addresses. 7. This Declaration of Covenant is intended to promote the efficient and effective management of surface water drainage on the Property, and it shall inure to the benefit of all the citizens of the City of Renton and its successors and assigns. This Declaration of Covenant shall run with the land and be binding upon Grantor(s), and Grantor's(s') successors in interest and assigns. 8. This Declaration of Covenant may be terminated by execution of a written agreement by the Owners and the City of Renton that is recorded by King County in its real property records. IN WITNESS WHEREOF, this Declaration of Covenant for the Maintenance and Inspection of Flow Control BMPs is executed this _____ day of ____________________, 20_____. GRANTOR, owner of the Property GRANTOR, owner of the Property STATE OF WASHINGTON ) COUNTY OF KING )ss. On this day personally appeared before me: , to me known to be the individual(s) described in and who executed the within and foregoing instrument and acknowledged that they signed the same as their free and voluntary act and deed, for the uses and purposes therein stated. Given under my hand and official seal this _____ day of ____________________, 20_____. Printed name Notary Public in and for the State of Washington, residing at My appointment expires FULL LEGAL DESCRIPTION:    THAT PORTION OF TRACT 244 IN C D HILLMAN'S LAKE WASHINGTON GARDEN OF EDEN ADDITION TO   SEATTLE DIVISION NO 4, ACCORDING TO THE PLAT THEREOF RECORDED IN VOLUME 11 OF PLATS,   PAGE 82, IN KING COUNTY, WASHINGTON, DESCRIBED AS FOLLOWS      BEGINNING AT A POINT ON THE WEST BOUNDARY LINE OF SAID TRACT, 301 FEET SOUTH OF THE   NORTHWEST CORNER OF SAID TRACT;   THENCE SOUTH 64 FEET;   THENCE EAST 252.3 FEET, MORE OR LESS, TO THE EAST BOUNDARY LINE OF SAID TRACT;    THENCE NORTH, ALONG SAID EAST BOUNDARY LINE, 64 FEET; THENCE WEST 252.3 FEET, MORE OR   LESS, TO POINT OF BEGINNING;    (BEING THE NORTH 365 FEET OF SAID TRACT 244, EXCEPT THE NORTH 301 FEET THEREOF).  Exhibit A: Flow Control BMP Site Plan MAINTENANCE INSTRUCTIONS FOR FULL INFILTRATION Your property contains an on-site BMP (best management practice) called “full infiltration,” which was installed to mitigate the stormwater quantity and quality impacts of some or all of the impervious surfaces on your property. Full infiltration is a method of soaking runoff from impervious area (such as paved areas and roofs) into the ground. If properly installed and maintained per Appendix A of the City of Renton’s Surface Water Design Manual, full infiltration can manage runoff so that a majority of precipitation events are absorbed. Infiltration devices, such as gravel filled trenches, drywells, and ground surface depressions, facilitate this process by putting runoff in direct contact with the soil and holding the runoff long enough to soak most of it into the ground. To be successful, the soil condition around the infiltration device must be reliably able to soak water into the ground for a reasonable number of years. Infiltration Devices The infiltration devices used on your property include the following as indicated on the site plan (CHECK THE BOX(ES) THAT APPLY): gravel filled trenches, drywells, ground surface depressions. MAINTENANCE RESTRICTIONS The size, placement, and composition of these devices as depicted by the site plan and design details must be maintained and may not be changed without written approval from the City of Renton or through a future development permit from the City of Renton. INSPECTION FREQUENCY AND MAINTENANCE GUIDELINES • Infiltration devices must be inspected annually and after major storm events to identify and repair any physical defects. • Maintenance and operation of the system should focus on ensuring the system’s viability by preventing sediment-laden flows from entering the device. Excessive sedimentation will result in a plugged or non-functioning facility. • If the infiltration device has a catch basin, sediment accumulation must be removed on a yearly basis or more frequently if necessary. • Prolonged ponding around or atop a device may indicate a plugged facility. If the device becomes plugged, it must be replaced. • Keeping the areas that drain to infiltration devices well swept and clean will enhance the longevity of these devices. • For roofs, frequent cleaning of gutters will reduce sediment loads to these devices. DRAFTx TYPICAL FULL INFILTRATION APPLICATIONS 6" 24" 12" 24" WASHED ROCK 1 12"- 34" LEVEL INFILTRATION TRENCH SECTION A NTS PLAN VIEW NTS SECTION VIEW NTS VARIES A A 6" 6" 4" RIGID OR 6"FLEXIBLE PERFORATED PIPE CB SUMP w/SOLID LID ROOF DRAIN 4" RIGID OR 6" FLEXIBLE PERFORATED PIPE OVERFLOW SPLASH BLOCK ROOF DRAIN CB SUMP w/SOLID LID 12" FINE MESHSCREEN SETBACK FROM BUILDING 5' MIN. 1' MIN.1' MIN. FILTER FABRIC COMPACTED BACKFILL 4" RIGID OR 6" FLEXIBLE PERFORATED PIPE 112" - 34" WASHED ROCK MIN. 1' ABOVE SEASONAL HIGH GROUNDWATER TABLE, SEE SECTION C.2.2.2 TRENCH SETBACK FROM BUILDING AS REQUIRED, 15' MIN. DRIVEWAY X-SECTION NTS 2' MIN. FILTER STRIP SEE SECTIONS 6.3.4 & 6.3.5 18" MIN. 6" MIN. 3/4" TO 1-1/2"WASHED DRAIN ROCK GRASS OVERFLOW NOTE:SEE C.2.2.3 FOR TRENCH LENGTHS, TRENCH SPACING ANDSITE LIMITATIONS MIN. 1' ABOVE SEASONAL HIGHGROUNDWATER TABLE, SEE SECTION C.2.2.2 X-SECTION NTS GRASS 2' MIN. 18" MIN. 6" MIN. 3/4" TO 1-1/2" WASHED DRAIN ROCK OVERFLOW 15' MIN. AS REQUIRED, SEE C.2.2.3 FROM ROOF NS T T S MIN. 1' ABOVESEASONAL HIGHGROUNDWATERTABLE, SEESECTION C.2.2.2 HOUSE FLOW 48 INCH DIAMETER HOLE FILLED WITH 1 12" - 3" WASHEDDRAIN ROCK SECTION NTS MARK CENTER OF HOLEWITH 1" CAPPED PVCOR OTHER MEANSFLUSH WITH SURFACE ROOF DOWNSPOUT OVERFLOW SPLASH BLOCK TOPSOIL FINE MESH SCREEN MIN. 4" DIA.PVC PIPE SIDES OF HOLE LINED WITHFILTER FABRIC CATCH BASIN (YARD DRAIN) 15' MIN. AS REQUIRED, SEE SECTION C.2.2.3 VARIES 1' MIN. MIN. 1' ABOVE SEASONALHIGH GROUNDWATER TABLE,SEE SECTION C.2.2.2 5' MIN. SETBACKFROM BUILDING FLOW PLAN VIEWNTS HOUSE ROOFDOWNSPOUT ROOFDOWNSPOUT CATCH BASIN(YARD DRAIN) 48 INCH DIAMETERHOLE FILLED WITH1 12" - 3" WASHEDDRAIN ROCK DRAFT Planning Division |1055 South Grady Way – 6th 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•BOND QUANTITY WORKSHEET INSTRUCTIONSThis 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 projectSection 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 entiretyInformation from this section auto‐populates to all other relevant areas of the workbookThis 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.Page 1 of 14Ref 8‐H Bond Quantity WorksheetINSTRUCTIONSUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########UnitReference # Price Unit Quantity CostBackfill & compaction‐embankmentESC‐16.50$                                            CY 130845.00Check dams, 4" minus rockESC‐2SWDM 5.4.6.380.00$                                          EachCatch Basin ProtectionESC‐335.50$                                          Each 6213.00Crushed surfacing 1 1/4" minusESC‐4WSDOT 9‐03.9(3)95.00$                                          CYDitchingESC‐59.00$                                            CYExcavation‐bulkESC‐62.00$                                            CY 510.00Fence, siltESC‐7SWDM 5.4.3.11.50$                                            LF 390585.00Fence, Temporary (NGPE)ESC‐81.50$                                            LF 3045.00Geotextile FabricESC‐92.50$                                            SYHay Bale Silt TrapESC‐100.50$                                            EachHydroseedingESC‐11SWDM 5.4.2.40.80$                                            SYInterceptor Swale / DikeESC‐121.00$                                            LFJute MeshESC‐13SWDM 5.4.2.23.50$                                            SYLevel SpreaderESC‐141.75$                                            LFMulch, by hand, straw, 3" deepESC‐15SWDM 5.4.2.12.50$                                            SYMulch, by machine, straw, 2" deepESC‐16SWDM 5.4.2.12.00$                                            SYPiping, temporary, CPP, 6"ESC‐1712.00$                                          LFPiping, temporary, CPP, 8"ESC‐1814.00$                                          LFPiping, temporary, CPP, 12"ESC‐1918.00$                                          LFPlastic covering, 6mm thick, sandbaggedESC‐20SWDM 5.4.2.34.00$                                            SY 6002,400.00Rip Rap, machine placed; slopesESC‐21WSDOT 9‐13.1(2)45.00$                                          CYRock Construction Entrance, 50'x15'x1'ESC‐22SWDM 5.4.4.11,800.00$                                    EachRock Construction Entrance, 100'x15'x1'ESC‐23SWDM 5.4.4.13,200.00$                                    EachSediment pond riser assemblyESC‐24SWDM 5.4.5.22,200.00$                                    EachSediment trap, 5'  high berm ESC‐25SWDM 5.4.5.119.00$                                          LFSed. trap, 5' high, riprapped spillway berm section ESC‐26SWDM 5.4.5.170.00$                                          LFSeeding, by handESC‐27SWDM 5.4.2.41.00$                                            SYSodding, 1" deep, level groundESC‐28SWDM 5.4.2.58.00$                                            SY 6004,800.00Sodding, 1" deep, sloped groundESC‐29SWDM 5.4.2.510.00$                                          SYTESC SupervisorESC‐30110.00$                                       HRWater truck, dust controlESC‐31SWDM 5.4.7140.00$                                       HRUnitReference # Price Unit Quantity CostEROSION/SEDIMENT SUBTOTAL: 8,898.00SALES TAX @ 10% 889.80EROSION/SEDIMENT TOTAL: 9,787.80(A)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR EROSION & SEDIMENT CONTROLDescription No.(A)WRITE‐IN‐ITEMS Page 3 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.a EROSION_CONTROLUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostGENERAL ITEMS Backfill & Compaction‐ embankment GI‐16.00$             CYBackfill & Compaction‐ trench GI‐29.00$             CY 1251,125.00Clear/Remove Brush, by hand (SY) GI‐31.00$             SYBollards ‐ fixed GI‐4 240.74$         EachBollards ‐ removable GI‐5 452.34$         EachClearing/Grubbing/Tree Removal GI‐6 10,000.00$   AcreExcavation ‐ bulk GI‐72.00$             CYExcavation ‐ Trench GI‐85.00$             CY 125625.00Fencing, cedar, 6' high GI‐9 20.00$           LFFencing, chain link, 4' GI‐10 38.31$           LFFencing, chain link, vinyl coated,  6' high GI‐11 20.00$           LFFencing, chain link, gate, vinyl coated,  20' GI‐12 1,400.00$     EachFill & compact ‐ common barrow GI‐13 25.00$           CYFill & compact ‐ gravel base GI‐14 27.00$           CYFill & compact ‐ screened topsoil GI‐15 39.00$           CYGabion, 12" deep, stone filled mesh GI‐16 65.00$           SYGabion, 18" deep, stone filled mesh GI‐17 90.00$           SYGabion, 36" deep, stone filled mesh GI‐18 150.00$         SYGrading, fine, by hand GI‐19 2.50$             SYGrading, fine, with grader GI‐20 2.00$             SYMonuments, 3' Long GI‐21 250.00$         EachSensitive Areas Sign GI‐22 7.00$             EachSodding, 1" deep, sloped ground GI‐23 8.00$             SYSurveying, line & grade GI‐24 850.00$         DaySurveying, lot location/lines GI‐25 1,800.00$     AcreTopsoil Type A (imported) GI‐26 28.50$           CYTraffic control crew ( 2 flaggers )GI‐27 120.00$         HRTrail, 4" chipped wood GI‐28 8.00$             SYTrail, 4" crushed cinder GI‐29 9.00$             SYTrail, 4" top course GI‐30 12.00$           SYConduit, 2" GI‐31 5.00$             LFWall, retaining, concrete GI‐32 55.00$           SFWall, rockery GI‐33 15.00$           SFSUBTOTAL THIS PAGE:1,750.00(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B) (C)Page 4 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B) (C)ROAD IMPROVEMENT/PAVEMENT/SURFACINGAC Grinding, 4' wide machine < 1000sy RI‐1 30.00$           SY 1123,360.00AC Grinding, 4' wide machine 1000‐2000sy RI‐2 16.00$           SYAC Grinding, 4' wide machine > 2000sy RI‐3 10.00$           SYAC Removal/Disposal RI‐4 35.00$           SY 1123,920.00Barricade, Type III ( Permanent )RI‐5 56.00$           LFGuard Rail RI‐6 30.00$           LFCurb & Gutter, rolled RI‐7 17.00$           LFCurb & Gutter, vertical RI‐8 12.50$           LFCurb and Gutter, demolition and disposal RI‐9 18.00$           LFCurb, extruded asphalt RI‐10 5.50$             LFCurb, extruded concrete RI‐11 7.00$             LFSawcut, asphalt, 3" depth RI‐12 1.85$             LFSawcut, concrete, per 1" depth RI‐13 3.00$             LFSealant, asphalt RI‐14 2.00$             LFShoulder, gravel, 4" thick RI‐15 15.00$           SYSidewalk, 4" thick RI‐16 38.00$           SYSidewalk, 4" thick, demolition and disposal RI‐17 32.00$           SYSidewalk, 5" thick RI‐18 41.00$           SYSidewalk, 5" thick, demolition and disposal RI‐19 40.00$           SYSign, Handicap RI‐20 85.00$           EachStriping, per stall RI‐21 7.00$             EachStriping, thermoplastic, ( for crosswalk )RI‐22 3.00$             SFStriping, 4" reflectorized line RI‐23 0.50$             LFAdditional 2.5" Crushed Surfacing RI‐24 3.60$             SYHMA 1/2" Overlay 1.5" RI‐25 14.00$           SYHMA 1/2" Overlay 2" RI‐26 18.00$           SY 1122,016.00HMA Road, 2", 4" rock, First 2500 SY RI‐27 28.00$           SYHMA Road, 2", 4" rock, Qty. over 2500SY RI‐28 21.00$           SYHMA Road, 4", 6" rock, First 2500 SY RI‐29 45.00$           SY 231,035.00HMA Road, 4", 6" rock, Qty. over 2500 SY RI‐30 37.00$           SYHMA Road, 4", 4.5" ATB RI‐31 38.00$           SYGravel Road, 4" rock, First 2500 SY RI‐32 15.00$           SYGravel Road, 4" rock, Qty. over 2500 SY RI‐33 10.00$           SYThickened Edge RI‐34 8.60$             LFSUBTOTAL THIS PAGE:10,331.00(B)(C)(D)(E)Page 5 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B) (C)PARKING LOT SURFACING No.2" AC, 2" top course rock & 4" borrow PL‐1 21.00$           SY2" AC,  1.5"  top course & 2.5" base course PL‐2 28.00$           SY4" select borrow PL‐35.00$             SY1.5" top course rock & 2.5" base course PL‐4 14.00$           SYSUBTOTAL PARKING LOT SURFACING:(B)(C)(D)(E)LANDSCAPING & VEGETATION No.Street Trees LA‐1Median Landscaping LA‐2Right‐of‐Way Landscaping LA‐3Wetland Landscaping LA‐4SUBTOTAL LANDSCAPING & VEGETATION:(B)(C)(D)(E)TRAFFIC & LIGHTING No.Signs TR‐1Street Light System ( # of Poles) TR‐2Traffic Signal TR‐3Traffic Signal Modification TR‐4SUBTOTAL TRAFFIC & LIGHTING:(B)(C)(D)(E)WRITE‐IN‐ITEMSSUBTOTAL WRITE‐IN ITEMS:STREET AND SITE IMPROVEMENTS SUBTOTAL: 12,081.00SALES TAX @ 10% 1,208.10STREET AND SITE IMPROVEMENTS TOTAL: 13,289.10(B)(C)(D)(E)Page 6 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostDRAINAGE (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$            EachThrough‐curb Inlet Framework D‐3 400.00$          EachCB Type ID‐4 1,500.00$      Each 11,500.00CB Type IL D‐5 1,750.00$      EachCB Type II, 48" diameter D‐6 2,300.00$      Each 12,300.0012,300.00     for additional depth over 4'    D‐7 480.00$          FT 41,920.001480.00CB Type II, 54" diameter D‐8 2,500.00$      Each     for additional depth over 4' D‐9 495.00$          FTCB Type II, 60" diameter D‐10 2,800.00$      Each     for additional depth over 4' D‐11 600.00$          FTCB Type II, 72" diameter D‐12 6,000.00$      Each     for additional depth over 4' D‐13 850.00$          FTCB Type II, 96" diameter D‐14 14,000.00$    Each     for additional depth over 4' D‐15 925.00$          FTTrash Rack, 12" D‐16 350.00$          EachTrash Rack, 15" D‐17 410.00$          EachTrash Rack, 18" D‐18 480.00$          EachTrash Rack, 21" D‐19 550.00$          EachCleanout, PVC, 4" D‐20 150.00$          EachCleanout, PVC, 6" D‐21 170.00$          EachCleanout, PVC, 8" D‐22 200.00$          EachCulvert, PVC, 4" D‐23 10.00$            LFCulvert, PVC, 6" D‐24 13.00$            LF 1401,820.00Culvert, PVC,  8" D‐25 15.00$            LFCulvert, PVC, 12" D‐26 23.00$            LFCulvert, PVC, 15" D‐27 35.00$            LFCulvert, PVC, 18" D‐28 41.00$            LFCulvert, PVC, 24" D‐29 56.00$            LFCulvert, PVC, 30" D‐30 78.00$            LFCulvert, PVC, 36" D‐31 130.00$          LFCulvert, CMP, 8" D‐32 19.00$            LFCulvert, CMP, 12" D‐33 29.00$            LFSUBTOTAL THIS PAGE:4,220.00 6,100.00(B) (C) (D) (E)Quantity Remaining (Bond Reduction) (B) (C)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESPage 7 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostQuantity Remaining (Bond Reduction) (B) (C)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESDRAINAGE (Continued)Culvert, CMP, 15" D‐34 35.00$            LFCulvert, CMP, 18" D‐35 41.00$            LFCulvert, CMP, 24" D‐36 56.00$            LFCulvert, CMP, 30" D‐37 78.00$            LFCulvert, CMP, 36" D‐38 130.00$          LFCulvert, CMP, 48" D‐39 190.00$          LFCulvert, CMP, 60" D‐40 270.00$          LFCulvert, CMP, 72" D‐41 350.00$          LFCulvert, Concrete, 8" D‐42 42.00$            LFCulvert, Concrete, 12" D‐43 48.00$            LFCulvert, Concrete, 15" D‐44 78.00$            LFCulvert, Concrete, 18" D‐45 48.00$            LFCulvert, Concrete, 24" D‐46 78.00$            LFCulvert, Concrete, 30" D‐47 125.00$          LFCulvert, Concrete, 36" D‐48 150.00$          LFCulvert, Concrete, 42" D‐49 175.00$          LFCulvert, Concrete, 48" D‐50 205.00$          LFCulvert, CPE Triple Wall, 6" D‐51 14.00$            LFCulvert, CPE Triple Wall, 8" D‐52 16.00$            LFCulvert, CPE Triple Wall, 12" D‐53 24.00$            LFCulvert, CPE Triple Wall, 15" D‐54 35.00$            LFCulvert, CPE Triple Wall, 18" D‐55 41.00$            LFCulvert, CPE Triple Wall, 24" D‐56 56.00$            LFCulvert, CPE Triple Wall, 30" D‐57 78.00$            LFCulvert, CPE Triple Wall, 36" D‐58 130.00$          LFCulvert, LCPE, 6" D‐59 60.00$            LFCulvert, LCPE, 8" D‐60 72.00$            LFCulvert, LCPE, 12" D‐61 84.00$            LFCulvert, LCPE, 15" D‐62 96.00$            LFCulvert, LCPE, 18" D‐63 108.00$          LFCulvert, LCPE, 24" D‐64 120.00$          LFCulvert, LCPE, 30" D‐65 132.00$          LFCulvert, LCPE, 36" D‐66 144.00$          LFCulvert, LCPE, 48" D‐67 156.00$          LFCulvert, LCPE, 54" D‐68 168.00$          LFSUBTOTAL THIS PAGE:(B) (C) (D) (E)Page 8 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostQuantity Remaining (Bond Reduction) (B) (C)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESDRAINAGE (Continued)Culvert, LCPE, 60" D‐69 180.00$          LFCulvert, LCPE, 72" D‐70 192.00$          LFCulvert, HDPE, 6" D‐71 42.00$            LFCulvert, HDPE, 8" D‐72 42.00$            LFCulvert, HDPE, 12" D‐73 74.00$            LFCulvert, HDPE, 15" D‐74 106.00$          LFCulvert, HDPE, 18" D‐75 138.00$          LFCulvert, HDPE, 24" D‐76 221.00$          LFCulvert, HDPE, 30" D‐77 276.00$          LFCulvert, HDPE, 36" D‐78 331.00$          LFCulvert, HDPE, 48" D‐79 386.00$          LFCulvert, HDPE, 54" D‐80 441.00$          LFCulvert, HDPE, 60" D‐81 496.00$          LFCulvert, HDPE, 72" D‐82 551.00$          LFPipe, Polypropylene, 6" D‐83 84.00$            LFPipe, Polypropylene, 8" D‐84 89.00$            LFPipe, Polypropylene, 12" D‐85 95.00$            LFPipe, Polypropylene, 15" D‐86 100.00$          LFPipe, Polypropylene, 18" D‐87 106.00$          LFPipe, Polypropylene, 24" D‐88 111.00$          LFPipe, Polypropylene, 30" D‐89 119.00$          LFPipe, Polypropylene, 36" D‐90 154.00$          LFPipe, Polypropylene, 48" D‐91 226.00$          LFPipe, Polypropylene, 54" D‐92 332.00$          LFPipe, Polypropylene, 60" D‐93 439.00$          LFPipe, Polypropylene, 72" D‐94 545.00$          LFCulvert, DI, 6" D‐95 61.00$            LFCulvert, DI, 8" D‐96 84.00$            LFCulvert, DI, 12" D‐97 106.00$          LF 525,512.002212.00Culvert, DI, 15" D‐98 129.00$          LFCulvert, DI, 18" D‐99 152.00$          LFCulvert, DI, 24" D‐100 175.00$          LFCulvert, DI, 30" D‐101 198.00$          LFCulvert, DI, 36" D‐102 220.00$          LFCulvert, DI, 48" D‐103 243.00$          LFCulvert, DI, 54" D‐104 266.00$          LFCulvert, DI, 60" D‐105 289.00$          LFCulvert, DI, 72" D‐106 311.00$          LFSUBTOTAL THIS PAGE:5,512.00 212.00(B) (C) (D) (E)Page 9 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostQuantity Remaining (Bond Reduction) (B) (C)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESSpecialty Drainage ItemsDitching SD‐19.50$              CYFlow Dispersal Trench    (1,436 base+) SD‐3 28.00$            LF French Drain  (3' depth) SD‐4 26.00$            LFGeotextile, laid in trench, polypropylene SD‐53.00$              SYMid‐tank Access Riser, 48" dia,  6' deep SD‐6 2,000.00$      EachPond Overflow Spillway SD‐7 16.00$            SYRestrictor/Oil Separator, 12" SD‐8 1,150.00$      EachRestrictor/Oil Separator, 15" SD‐9 1,350.00$      EachRestrictor/Oil Separator, 18" SD‐10 1,700.00$      EachRiprap, placed SD‐11 42.00$            CYTank End Reducer (36" diameter) SD‐12 1,200.00$      EachInfiltration pond testing SD‐13 125.00$          HRPermeable Pavement SD‐14Permeable Concrete Sidewalk SD‐15Culvert, Box      __ ft  x  __ ft SD‐16SUBTOTAL SPECIALTY DRAINAGE ITEMS:(B) (C) (D) (E)STORMWATER FACILITIES (Include Flow Control and Water Quality Facility Summary Sheet and Sketch)Detention Pond SF‐1Each Detention Tank SF‐2Each Detention Vault SF‐3Each Infiltration Pond SF‐4Each Infiltration Tank SF‐5Each Infiltration Vault SF‐6Each Infiltration Trenches SF‐7 3,122.00$      Each 13,122.00Basic Biofiltration Swale SF‐8Each Wet Biofiltration Swale SF‐9Each 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:3,122.00(B) (C) (D) (E)Page 10 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostQuantity Remaining (Bond Reduction) (B) (C)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESWRITE‐IN‐ITEMS (INCLUDE ON‐SITE BMPs)StormFilter WI‐1 5,500.00$      15,500.00WI‐2WI‐3WI‐4WI‐5WI‐6WI‐7WI‐8WI‐9WI‐10WI‐11WI‐12WI‐13WI‐14WI‐15SUBTOTAL WRITE‐IN ITEMS:5,500.00DRAINAGE AND STORMWATER FACILITIES SUBTOTAL: 9,732.00 14,934.00SALES TAX @ 10% 973.20 1,493.40DRAINAGE AND STORMWATER FACILITIES TOTAL: 10,705.20 16,427.40(B) (C) (D) (E)Page 11 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostConnection to Existing Watermain W‐1 2,000.00$     Each 12,000.00Ductile Iron Watermain, CL 52, 4 Inch Diameter W‐2 50.00$           LFDuctile Iron Watermain, CL 52, 6 Inch Diameter W‐3 56.00$           LFDuctile Iron Watermain, CL 52, 8 Inch Diameter W‐4 60.00$           LFDuctile Iron Watermain, CL 52, 10 Inch Diameter W‐5 70.00$           LFDuctile Iron Watermain, CL 52, 12 Inch Diameter W‐6 80.00$           LFGate Valve, 4 inch Diameter W‐7 500.00$         EachGate Valve, 6 inch Diameter W‐8 700.00$         EachGate Valve, 8 Inch Diameter W‐9 800.00$         EachGate Valve, 10 Inch Diameter W‐10 1,000.00$     EachGate Valve, 12 Inch Diameter W‐11 1,200.00$     EachFire Hydrant Assembly W‐12 4,000.00$     EachPermanent Blow‐Off Assembly W‐13 1,800.00$     EachAir‐Vac Assembly,  2‐Inch Diameter W‐14 2,000.00$     EachAir‐Vac Assembly,  1‐Inch Diameter W‐15 1,500.00$     EachCompound Meter Assembly 3‐inch Diameter W‐16 8,000.00$     EachCompound Meter Assembly 4‐inch Diameter W‐17 9,000.00$     EachCompound Meter Assembly 6‐inch Diameter W‐18 10,000.00$   EachPressure Reducing Valve Station 8‐inch to 10‐inch W‐19 20,000.00$   EachWATER SUBTOTAL:2,000.00SALES TAX @ 10% 200.00WATER TOTAL: 2,200.00(B) (C) (D) (E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR WATERQuantity Remaining (Bond Reduction) (B) (C)Page 12 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.d WATERUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 CED Permit #:########Existing Future Public PrivateRight‐of‐Way Improvements Improvements(D)(E)Description No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostClean Outs SS‐1 1,000.00$     Each 22,000.00Grease Interceptor, 500 gallon SS‐2 8,000.00$     EachGrease Interceptor, 1000 gallon SS‐3 10,000.00$   EachGrease Interceptor, 1500 gallon SS‐4 15,000.00$   EachSide Sewer Pipe, PVC. 4 Inch Diameter SS‐5 80.00$           LFSide Sewer Pipe, PVC. 6 Inch Diameter SS‐6 95.00$           LF 403,800.0013012,350.00Sewer Pipe, PVC, 8 inch Diameter SS‐7 105.00$         LFSewer Pipe, PVC, 12 Inch Diameter SS‐8 120.00$         LFSewer Pipe, DI, 8 inch Diameter SS‐9 115.00$         LFSewer Pipe, DI, 12 Inch Diameter SS‐10 130.00$         LFManhole, 48 Inch Diameter SS‐11 6,000.00$     EachManhole, 54 Inch Diameter SS‐13 6,500.00$     EachManhole, 60 Inch Diameter SS‐15 7,500.00$     EachManhole, 72 Inch Diameter SS‐17 8,500.00$     EachManhole, 96 Inch Diameter SS‐19 14,000.00$   EachPipe, C‐900, 12 Inch Diameter SS‐21 180.00$         LFOutside Drop SS‐24 1,500.00$     LSInside Drop SS‐25 1,000.00$     LSSewer Pipe, PVC, ____ Inch Diameter SS‐26Lift Station (Entire System) SS‐27 LSSANITARY SEWER SUBTOTAL:3,800.00 14,350.00SALES TAX @ 10% 380.00 1,435.00SANITARY SEWER TOTAL: 4,180.00 15,785.00(B) (C) (D) (E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR SANITARY SEWERQuantity Remaining (Bond Reduction) (B) (C)Page 13 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.e SANITARY SEWERUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 Planning Division |1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430‐7200Date: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)19,669.10$                                                   Future Public Improvements Subtotal(c)‐$                                                               Stormwater & Drainage Facilities (Public & Private) Subtotal(d) (d)27,132.60$                                                   (e)(f)Site RestorationCivil Construction PermitMaintenance Bond9,360.34$                                                     Bond Reduction2Construction Permit Bond Amount 3Minimum Bond Amount is $10,000.001 Estimate Only  ‐ May involve multiple and variable components, which will be established on an individual basis by Development Engineering.2 The City of Renton allows one request only for bond reduction prior to the maintenance period. Reduction of not more than 70% of the original bond amount, provided that the remaining 30% willcover all remaining items to be constructed. 3 Required Bond Amounts are subject to review and modification by Development Engineering.* Note: The word BOND as used in this document means any financial guarantee acceptable to the City of Renton.** Note: All prices include labor, equipment, materials, overhead and profit. EST1((b) + (c) + (d)) x 20%‐$                                                           MAINTENANCE BOND */**(after final acceptance of construction)9,787.80$                                                 19,669.10$                                               56,636.25$                                               9,787.80$                                                 ‐$                                                           27,132.60$                                               ‐$                                                           66,424.05$                                               P (a) x 100%SITE IMPROVEMENT BOND QUANTITY WORKSHEET BOND CALCULATIONS6/12/2017Greg Guillen25385CG EngineeringR((b x 150%) + (d x 100%))S(e) x 150% + (f) x 100%Bond Reduction: Existing Right‐of‐Way Improvements (Quantity Remaining)2Bond Reduction: Stormwater & Drainage Facilities (Quantity Remaining)2T(P +R ‐ S)Prepared by:Project InformationCONSTRUCTION BOND AMOUNT */**(prior to permit issuance)425.778.8500grego@cgengineering.comAberdeen Ave Short PlatLUA 16‐0009671824 Aberdeen Ave NE3343901606FOR APPROVAL########250 4th Ave S, Suite 200Page 14 of 14Ref 8‐H Bond Quantity WorksheetSECTION III. BOND WORKSHEETUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 1/29/2018 Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com TIR Section X – Operation and Maintenance Manual TIR Section X Summary: Narrative Maintenance Sheets Maintenance sheets from Appendix A of the 2017 RSWDM are provided in the following pages for the proposed drainage system. Please note that the site plan is generated during the design phase and may not reflect all changes made in permitting and construction. CG Engineering may be contacted for an updated copy of the plan once the as-built drawings are completed for the site. The drainage system consists of catch basins and manholes, conveyance pipes, grounds (landscaping), a gravel filled infiltration trench BMP, soil amendment BMP, and a proprietary facility cartridge filter system (Contech StormFilter). The project contractor will be responsible for passing along the information in this maintenance manual to the owner. Upon request by the City, it shall be made available for their inspection. Facilities shall be inspected for defects. The frequency of this should occur annually. Most maintenance tasks are generally reactionary to a defect being found, rather than a matter of constant upkeep. It is generally expected that few to none of these defects will be present upon the yearly inspection of each facility. Unless otherwise noted on the facility sheets the maintenance tasks should be performed on an “as needed” basis: (a) when the described defect is visible to whomever performs the yearly inspection, or (b) should any defect become apparent between inspections. Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 2 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 3 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 4 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 5 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 6 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com Aberdeen Ave Subdivision 16037.20 May 19, 2017 Technical Information Report Section X, Page 7 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph. 425.778.8500 | f. 425.778.5536 www.cgengineering.com StormFilter Inspection and Maintenance Procedures ENGINEERED SOLUTIONS In addition to these two activities, it is important to check the condition of the StormFilter unit after major storms for potential damage caused by high flows and for high sediment accumulation that may be caused by localized erosion in the drainage area. It may be necessary to adjust the inspection/ maintenance schedule depending on the actual operating conditions encountered by the system. In general, inspection activities can be conducted at any time, and maintenance should occur, if warranted, during dryer months in late summer to early fall. Maintenance Frequency The primary factor for determining frequency of maintenance for the StormFilter is sediment loading. A properly functioning system will remove solids from water by trapping particulates in the porous structure of the filter media inside the cartridges. The flow through the system will naturally decrease as more and more particulates are trapped. Eventually the flow through the cartridges will be low enough to require replacement. It may be possible to extend the usable span of the cartridges by removing sediment from upstream trapping devices on a routine as-needed basis, in order to prevent material from being re-suspended and discharged to the StormFilter treatment system. The average maintenance lifecycle is approximately 1-5 years. Site conditions greatly influence maintenance requirements. StormFilter units located in areas with erosion or active construction may need to be inspected and maintained more often than those with fully stabilized surface conditions. Regulatory requirements or a chemical spill can shift maintenance timing as well. The maintenance frequency may be adjusted as additional monitoring information becomes available during the inspection program. Areas that develop known problems should be inspected more frequently than areas that demonstrate no problems, particularly after major storms. Ultimately, inspection and maintenance activities should be scheduled based on the historic records and characteristics of an individual StormFilter system or site. It is recommended that the site owner develop a database to properly manage StormFilter inspection and maintenance programs.. 2 Maintenance Guidelines The primary purpose of the Stormwater Management StormFilter® is to filter and prevent pollutants from entering our waterways. Like any effective filtration system, periodically these pollutants must be removed to restore the StormFilter to its full efficiency and effectiveness. Maintenance requirements and frequency are dependent on the pollutant load characteristics of each site. Maintenance activities may be required in the event of a chemical spill or due to excessive sediment loading from site erosion or extreme storms. It is a good practice to inspect the system after major storm events. Maintenance Procedures Although there are many effective maintenance options, we believe the following procedure to be efficient, using common equipment and existing maintenance protocols. The following two-step procedure is recommended:: 1. Inspection • Inspection of the vault interior to determine the need for maintenance. 2. Maintenance • Cartridge replacement • Sediment removal Inspection and Maintenance Timing At least one scheduled inspection should take place per year with maintenance following as warranted. First, an inspection should be done before the winter season. During the inspection the need for maintenance should be determined and, if disposal during maintenance will be required, samples of the accumulated sediments and media should be obtained. Second, if warranted, a maintenance (replacement of the filter cartridges and removal of accumulated sediments) should be performed during periods of dry weather. 3 Inspection Procedures The primary goal of an inspection is to assess the condition of the cartridges relative to the level of visual sediment loading as it relates to decreased treatment capacity. It may be desirable to conduct this inspection during a storm to observe the relative flow through the filter cartridges. If the submerged cartridges are severely plugged, then typically large amounts of sediments will be present and very little flow will be discharged from the drainage pipes. If this is the case, then maintenance is warranted and the cartridges need to be replaced. Warning: In the case of a spill, the worker should abort inspection activities until the proper guidance is obtained. Notify the local hazard control agency and Contech Engineered Solutions immediately. To conduct an inspection: Important: Inspection should be performed by a person who is familiar with the operation and configuration of the StormFilter treatment unit. 1. If applicable, set up safety equipment to protect and notify surrounding vehicle and pedestrian traffic. 2. Visually inspect the external condition of the unit and take notes concerning defects/problems. 3. Open the access portals to the vault and allow the system vent. 4. Without entering the vault, visually inspect the inside of the unit, and note accumulations of liquids and solids. 5. Be sure to record the level of sediment build-up on the floor of the vault, in the forebay, and on top of the cartridges. If flow is occurring, note the flow of water per drainage pipe. Record all observations. Digital pictures are valuable for historical documentation. 6. Close and fasten the access portals. 7. Remove safety equipment. 8. If appropriate, make notes about the local drainage area relative to ongoing construction, erosion problems, or high loading of other materials to the system. 9. Discuss conditions that suggest maintenance and make decision as to weather or not maintenance is needed. Maintenance Decision Tree The need for maintenance is typically based on results of the inspection. The following Maintenance Decision Tree should be used as a general guide. (Other factors, such as Regulatory Requirements, may need to be considered) 1. Sediment loading on the vault floor. a. If >4” of accumulated sediment, maintenance is required. 2. Sediment loading on top of the cartridge. a. If >1/4” of accumulation, maintenance is required. 3. Submerged cartridges. a. If >4” of static water above cartridge bottom for more than 24 hours after end of rain event, maintenance is required. (Catch basins have standing water in the cartridge bay.) 4. Plugged media. a. If pore space between media granules is absent, maintenance is required. 5. Bypass condition. a. If inspection is conducted during an average rain fall event and StormFilter remains in bypass condition (water over the internal outlet baffle wall or submerged cartridges), maintenance is required. 6. Hazardous material release. a. If hazardous material release (automotive fluids or other) is reported, maintenance is required. 7. Pronounced scum line. a. If pronounced scum line (say ≥ 1/4” thick) is present above top cap, maintenance is required. Important: Care must be used to avoid damaging the cartridges during removal and installation. The cost of repairing components damaged during maintenance will be the responsibility of the owner. C. Set the used cartridge aside or load onto the hauling truck. D. Continue steps a through c until all cartridges have been removed. Method 2: A. This activity will require that maintenance personnel enter the vault to remove the cartridges from the under drain manifold and place them under the vault opening for lifting (removal). Disconnect each filter cartridge from the underdrain connector by rotating counterclockwise 1/4 of a turn. Roll the loose cartridge, on edge, to a convenient spot beneath the vault access. B. Unscrew the cartridge cap. C. Remove the cartridge hood and float. D. At location under structure access, tip the cartridge on its side. E. Empty the cartridge onto the vault floor. Reassemble the empty cartridge. F. Set the empty, used cartridge aside or load onto the hauling truck. G. Continue steps a through e until all cartridges have been removed. 4 Maintenance Depending on the configuration of the particular system, maintenance personnel will be required to enter the vault to perform the maintenance. Important: If vault entry is required, OSHA rules for confined space entry must be followed. Filter cartridge replacement should occur during dry weather. It may be necessary to plug the filter inlet pipe if base flows is occurring. Replacement cartridges can be delivered to the site or customers facility. Information concerning how to obtain the replacement cartridges is available from Contech Engineered Solutions. Warning: In the case of a spill, the maintenance personnel should abort maintenance activities until the proper guidance is obtained. Notify the local hazard control agency and Contech Engineered Solutions immediately. To conduct cartridge replacement and sediment removal maintenance: 1. If applicable, set up safety equipment to protect maintenance personnel and pedestrians from site hazards. 2. Visually inspect the external condition of the unit and take notes concerning defects/problems. 3. Open the doors (access portals) to the vault and allow the system to vent. 4. Without entering the vault, give the inside of the unit, including components, a general condition inspection. 5. Make notes about the external and internal condition of the vault. Give particular attention to recording the level of sediment build-up on the floor of the vault, in the forebay, and on top of the internal components. 6. Using appropriate equipment offload the replacement cartridges (up to 150 lbs. each) and set aside. 7. Remove used cartridges from the vault using one of the following methods: Method 1: A. This activity will require that maintenance personnel enter the vault to remove the cartridges from the under drain manifold and place them under the vault opening for lifting (removal). Disconnect each filter cartridge from the underdrain connector by rotating counterclockwise 1/4 of a turn. Roll the loose cartridge, on edge, to a convenient spot beneath the vault access. Using appropriate hoisting equipment, attach a cable from the boom, crane, or tripod to the loose cartridge. Contact Contech Engineered Solutions for suggested attachment devices. B. Remove the used cartridges (up to 250 lbs. each) from the vault. 5 8. Remove accumulated sediment from the floor of the vault and from the forebay. This can most effectively be accomplished by use of a vacuum truck. 9. Once the sediments are removed, assess the condition of the vault and the condition of the connectors. 10. Using the vacuum truck boom, crane, or tripod, lower and install the new cartridges. Once again, take care not to damage connections. 11. Close and fasten the door. 12. Remove safety equipment. 13. Finally, dispose of the accumulated materials in accordance with applicable regulations. Make arrangements to return the used empty cartridges to Contech Engineered Solutions. Related Maintenance Activities - Performed on an as-needed basis StormFilter units are often just one of many structures in a more comprehensive stormwater drainage and treatment system. In order for maintenance of the StormFilter to be successful, it is imperative that all other components be properly maintained. The maintenance/repair of upstream facilities should be carried out prior to StormFilter maintenance activities. In addition to considering upstream facilities, it is also important to correct any problems identified in the drainage area. Drainage area concerns may include: erosion problems, heavy oil loading, and discharges of inappropriate materials. Material Disposal The accumulated sediment found in stormwater treatment and conveyance systems must be handled and disposed of in accordance with regulatory protocols. It is possible for sediments to contain measurable concentrations of heavy metals and organic chemicals (such as pesticides and petroleum products). Areas with the greatest potential for high pollutant loading include industrial areas and heavily traveled roads. Sediments and water must be disposed of in accordance with all applicable waste disposal regulations. When scheduling maintenance, consideration must be made for the disposal of solid and liquid wastes. This typically requires coordination with a local landfill for solid waste disposal. For liquid waste disposal a number of options are available including a municipal vacuum truck decant facility, local waste water treatment plant or on-site treatment and discharge. Inspection Report Date: Personnel: Location: ————————————System Size: ——————————————————————————————————— System Type: Vault Cast-In-Place Linear Catch Basin Manhole Other Sediment Thickness in Forebay: ——————————————————————————————————————————— Sediment Depth on Vault Floor: ——————————————————————————————————————————— Structural Damage: ———————————————————————————————————————————————— Estimated Flow from Drainage Pipes (if available): ———————————————————————————————————— Cartridges Submerged: Yes No Depth of Standing Water: —————————————————————— StormFilter Maintenance Activities (check off if done and give description) Trash and Debris Removal: ——————————————————————————————————————————— Minor Structural Repairs: ———————————————————————————————————————————— Drainage Area Report ————————————————————————————————————————————— Excessive Oil Loading: Yes No Source: ——————————————————————— Sediment Accumulation on Pavement: Yes No Source: ——————————————————————— Erosion of Landscaped Areas: Yes No Source: ——————————————————————— Items Needing Further Work: ———————————————————————————————————————————— Owners should contact the local public works department and inquire about how the department disposes of their street waste residuals. Other Comments: ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— Review the condition reports from the previous inspection visits. Date: StormFilter Maintenance Report Date: —————————————Personnel: ———————————————————————————————————— Location: ————————————System Size: ——————————————————————————————————— System Type: Vault Cast-In-Place Linear Catch Basin Manhole Other List Safety Procedures and Equipment Used: —————————————————————————————————————— ————————————————————————————————————————————————————————— ————————————————————————————————————————————————————————— System Observations Months in Service: Oil in Forebay (if present): Yes No Sediment Depth in Forebay (if present): ———————————————————————————————————————— Sediment Depth on Vault Floor: ——————————————————————————————————————————— Structural Damage: ———————————————————————————————————————————————— Drainage Area Report Excessive Oil Loading: Yes No Source: ————————————————————————— Sediment Accumulation on Pavement: Yes No Source: ————————————————————————— Erosion of Landscaped Areas: Yes No Source: ————————————————————————— StormFilter Cartridge Replacement Maintenance Activities Remove Trash and Debris: Yes No Details: —————————————————————————— Replace Cartridges: Yes No Details: —————————————————————————— Sediment Removed: Yes No Details: —————————————————————————— Quantity of Sediment Removed (estimate?): Minor Structural Repairs: Yes No Details: ————————————————————————— Residuals (debris, sediment) Disposal Methods: —————————————————————————————————————— Notes: —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— 800.338.1122 www.conteches.com NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS AN EXPRESSED WARRANT Y OR AN IMPLIED WARRANT Y OF MERCHANTABILITY OR FITNESS FOR AN Y PARTICULAR PURPOSE . SEE THE CONTECH STANDARD CONDITIONS OF SALE (VIEWABLE AT WWW.CONTECHES.COM /COS ) FOR MORE INFORMATION . Contech Engineered Solutions LLC provides site solutions for the civil engineering industry. Contech’s portfolio includes bridges, drainage, sanitary sewer, stormwater and earth stabilization products. For information on other Contech division offerings, visit contech-cpi.com or call 800.338.1122. Support • Drawings and specifications are available at www.conteches.com. • Site-specific design support is available from our engineers. ENGINEERED SOLUTIONS ©2016 CONTECH ENGINEERED SOLUTIONS LLC. 800-338-1122 www.ContechES.com All Rights Reserved. Printed in the USA. StormFilter Inspection and Maintenance Procedures 8/2016