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Home My WebLink AboutC21-004477_ TIR FINAL TECHNICAL INFORMATION REPORT FOR Hardy Short Plat CITY OF RENTON, WASHINGTON Prepared by: Christian R. Vanderhoeven, E.I.T Approved by: Sheri H. Murata, P.E. Date: December 10, 2021, January 14, 2022 Core No.: 21019 1/14/22 DEVELOPMENT ENGINEERING YQI 01/26/2022 SURFACE WATER UTILITY JFarah 01/26/2022 Core Design, Inc. HARDY SHORT PLAT i Hardy Short Plat Table of Contents 1. PROJECT OVERVIEW .......................................................................................................................... 1-1 Figure 1-1 Vicinity Map ..................................................................................................................... 1-1 2. CONDITIONS AND REQUIREMENTS SUMMARY ................................................................................ 2-1 2.1 Core Requirements .......................................................................................................................... 2-2 2.1.1 Core Requirement #1: Discharge at the Natural Location ...................................................... 2-2 2.1.2 Core Requirement #2: Offsite Analysis .................................................................................... 2-2 2.1.3 Core Requirement #3: Flow Control......................................................................................... 2-2 2.1.4 Core Requirement #4: Conveyance System ............................................................................. 2-2 2.1.5 Core Requirements #5: Erosion and Sediment Control ........................................................... 2-2 2.1.6 Core Requirement #6: Maintenance and Operations .............................................................. 2-2 2.1.7 Core Requirement #7: Financial Guarantees and Liability ....................................................... 2-2 2.1.8 Core Requirement #8: Water Quality ...................................................................................... 2-2 2.1.9 Core Requirement #9: On-Site BMPs ....................................................................................... 2-2 2.2 Special Requirements ...................................................................................................................... 2-2 2.2.1 Special Requirement #1: Other Adopted Area Specific Requirements .................................... 2-2 2.2.2 Special Requirement #2: Flood Hazard Area Delineation ........................................................ 2-3 2.2.3 Special Requirement #3: Flood Protection Facilities ................................................................ 2-3 2.2.4 Special Requirement #4: Source Control ................................................................................. 2-3 2.2.5 Special Requirement #5: Oil Control ........................................................................................ 2-3 2.2.6 Special Requirement #6: Aquifer Protection Area ................................................................... 2-3 3. OFFSITE ANALYSIS ............................................................................................................................. 3-1 Task 1 Study Area Definition and Maps ................................................................................................. 3-1 Task 2 Resource Review ........................................................................................................................ 3-1 Sensitive Areas Folio.......................................................................................................................... 3-1 Task 3 Field Investigation ...................................................................................................................... 3-1 Task 4 Drainage System Description and Problem Description ............................................................ 3-1 4. FLOW CONTROL AND WATER QUALITY ANALYSIS ............................................................................ 4-1 4.1 Predeveloped Site Hydrology .......................................................................................................... 4-1 Table 4-1 Predeveloped Conditions .................................................................................................. 4-1 Core Design, Inc. HARDY SHORT PLAT ii Predeveloped Bypass/Intercepted Mitigation Trade ........................................................................ 4-1 4.2 Developed Site Hydrology ............................................................................................................... 4-1 Table 4-2 Developed Conditions ....................................................................................................... 4-2 Developed Bypass/Intercepted Mitigation Trade ............................................................................. 4-2 4.3 Flow Control System ........................................................................................................................ 4-4 4.4 BMP Feasibility ................................................................................................................................ 4-6 4.5 Water Quality Treatment Analysis and Design ................................................................................ 4-9 Table 4-3 PGIS Areas ......................................................................................................................... 4-9 5. DOWNSTREAM CONVEYANCE SYSTEM CAPACITY ANALYSIS ............................................................ 5-1 6. SPECIAL REPORTS AND STUDIES ....................................................................................................... 6-1 7. OTHER PERMITS ................................................................................................................................ 7-1 8. ESC ANALYSIS AND DESIGN ............................................................................................................... 8-1 9. BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT ............................. 9-1 9.1 Bond Quantities ............................................................................................................................... 9-1 9.2 Facility Summaries ........................................................................................................................... 9-1 9.3 Declaration of Covenant .................................................................................................................. 9-1 10. OPERATIONS AND MAINTENANCE .................................................................................................. 10-1 Appendix A ............................................................................................................................................... 10-2 Core Design, Inc. HARDY SHORT PLAT Page 1-1 1. PROJECT OVERVIEW The proposed Hardy Short Plat project is located at 857 Field Avenue NE, Renton, WA 98059. See Vicinity Map below. Figure 1-1 Vicinity Map The site is composed of a single parcel number: 1437650040 with an area of approximately 0.35 acres. The total site area, including frontage, is approximately 0.37 acres. The site is bordered by Field Avenue NE to the east and residential homes to the north, south, and west. The site was previously developed with a single-story residential home. The site generally slopes at 5- 10% from east to west. Proposed development of the property will include the demolition of all existing structures and the construction of two single family residences, shared driveway, utilities, detention vault, and frontage improvements. The subject project’s drainage facilities were designed using the guidelines and requirements established in Section 1.2.3.1 of the 2017 City of Renton Surface Water Design Manual (RSWDM). The Flow Control Duration Standard matching forested site conditions is required for this project. 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 ________ ShorelineManagement StructuralRockery/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 (NA) Tuscany Construction 206-714-6707 PO Box 6127 Bellevue, WA 98008 Sheri H. Murata Core Design 425-885-7877 Hardy Short Plat XXX 23 N 5 E NW 10 857 Field Avenue NE Renton, WA 98059 3/10/21 March 10, 2021 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 NA NA Lower Cedar River 2016 KCSWDM as amended by the city of Renton Till 0-10%Low 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 Majority of soils not suitable for infiltration Onsite Basin NA TBD Does not trigger any WQ Thresholds 1 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 Vault KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS  Drainage Easement  Covenant  Native Growth Protection Covenant  Tract  Other ___________________________  Cast in Place Vault  Retaining Wall  Rockery > 4’ High  Structural on Steep Slope  Other ______________________________ Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knowledge the information provided here is accurate. Signed/Date 2016 Surface Water Design Manual 4/24/2016 5 12/10/21 Core Design, Inc. HARDY SHORT PLAT Page 2-1 2. CONDITIONS AND REQUIREMENTS SUMMARY The proposed project is classified as requiring “Directed Drainage Review” per Page 1-8 Definitions given in the 2017 RSWDM. Therefore, all nine core requirements and six special requirements will be addressed per Section 1.2 and 1.3 of the 2017 RSWDM. Core Design, Inc. HARDY SHORT PLAT Page 2-2 2.1 Core Requirements 2.1.1 Core Requirement #1: Discharge at the Natural Location The existing site drainage exits the site via sheet flow over the west site boundary and passes through neighboring properties for 200 ft before entering the city’s conveyance system along Duvall Pl NE. The proposed project will not discharge flow across the west site boundary but redirect flow north along the west site boundary to combine with the same existing city conveyance system. The existing and proposed drainage path will combine within 300 ft. 2.1.2 Core Requirement #2: Offsite Analysis See Section 3 of this Report for the downstream drainage path. 2.1.3 Core Requirement #3: Flow Control The proposed detention vault is designed to fall within the City’s Flow Control Duration Standard (Forested Site Conditions). This flow control standard requires matching historical forested conditions from 50% of the 2 -year flow up to the full 50-year flow. See Section 4 of this report for a detailed Flow Control Analysis. 2.1.4 Core Requirement #4: Conveyance System Conveyance Calculations will be provided in Section 5 to show that the proposed conveyance system provides sufficient capacity for the 25-year storm as calculated by the Rational Method. 2.1.5 Core Requirements #5: Erosion and Sediment Control Erosion and sediment control will be provided through catch basin protection, silt fencing, tree protection fencing, and an existing asphalt driveway to be used for construction access entrance. See Section 8 of this report for erosion and sediment control analysis and design. 2.1.6 Core Requirement #6: Maintenance and Operations The property owner will be responsible for the maintenance and operations of the stormwater facility located in the shared driveway. An Operations and Maintenance Manual will be provided in Section 10. 2.1.7 Core Requirement #7: Financial Guarantees and Liability A bond quantities worksheet has been provided in Section 9. 2.1.8 Core Requirement #8: Water Quality The project is required to provide basic water quality treatment if the new plus replaced pollution generating impervious surface exceeds 5,000 SF. The project proposes 3,201 square feet which does not exceed this threshold. See Section 4.5 for details. 2.1.9 Core Requirement #9: On-Site BMPs The project site is less than 22,000 square feet; this site falls under Small Lot BMP Requirements. See Section 4.4 of this report for discussion on how this Core Requirement is addressed. 2.2 Special Requirements 2.2.1 Special Requirement #1: Other Adopted Area Specific Requirements Core Design, Inc. HARDY SHORT PLAT Page 2-3 There are no known additional requirements for the subject project. 2.2.2 Special Requirement #2: Flood Hazard Area Delineation Not applicable since the project does not contain nor is adjacent to a flood hazard area. 2.2.3 Special Requirement #3: Flood Protection Facilities Not applicable since the project does not rely on an existing flood protection facility or plans to modify or construct a new flood protection facility. 2.2.4 Special Requirement #4: Source Control This special requirement does not apply as the project does not require a commercial site development permit. 2.2.5 Special Requirement #5: Oil Control Not applicable since the project is not a high use site. The expected average daily traffic is less than 100 vehicles per 1,000 square feet of gross building area. 2.2.6 Special Requirement #6: Aquifer Protection Area Not applicable since the project is not in an Aquifer Protection Area. Core Design, Inc. HARDY SHORT PLAT Page 3-1 3. OFFSITE ANALYSIS Task 1 Study Area Definition and Maps The proposed project is located within the Lower Cedar River drainage basin. Task 2 Resource Review Sensitive Areas Folio Renton GIS was reviewed for sensitive areas. The proposed project site does not fall within the following sensitive areas: coal mines, erosion hazard, flood hazard, floodway, channel migration zone, landslide, seismic hazard, regulated stream, wetland, or wellhead protection. Task 3 Field Investigation There is negligible upstream tributary area. Downstream Drainage Path Runoff from the site initially sheet flows across the western site boundary through the neighboring properties until it reaches Duvall Pl NE. At this point the runoff follows the grade of the road north where it enters an existing catch basin. The runoff is directed to the south side of NE 9th Street at which point it continues north for approximately 110 ft before entering an existing storm pond. The pond will detain the storm runoff and discharge at acceptable flow rates to the west at which point the ¼ mile analysis will end. The runoff will eventually enter the Maplewood Creek and into the Cedar River. See the following page for a downstream route exhibit. Task 4 Drainage System Description and Problem Description Drainage complaints were researched within a quarter mile of the project site. Parcel 1437650230 north of the project site recorded the lone drainage complaint within this range. The complaint was described as “Facility Seeping Water” and was closed on June 21, 1991. 4,514 376 WGS_1984_Web_Mercator_Auxiliary_Sphere Downstream Map - Renton This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. THIS MAP IS NOT TO BE USED FOR NAVIGATION Notes None Legend 256 0 128 256 Feet Information Technology - GIS RentonMapSupport@Rentonwa.gov 11/17/2021 City and County Labels Addresses Parcels City and County Boundary <all other values> Renton Network Structures Access Riser Inlet Manhole Utility Vault Clean Out Unknown Control Structure Detention Facilities Pond Tank Vault Bioswale Wetland Other Surface Water Main Culvert Open Drains Facility Outline Drainage Complaints Known Drainage Issues Renton King County Streets Points of Interest Parks Waterbodies 2019.sid Red: Band_1 Green: Band_2 Blue: Band_3 Site Seeping water complaint on this parcel Core Design, Inc. HARDY SHORT PLAT Page 4-1 4. FLOW CONTROL AND WATER QUALITY ANALYSIS A flow control facility is proposed for the project. See section 4.1 below for details. A water quality treatment facility is not proposed as the project does not trigger any requirements for water quality treatment as delineated in Section 4.5 of this Report. The drainage analysis was modeled using MGS Flood software. 4.1 Predeveloped Site Hydrology The site was previously developed with a single-story residential home. The rest of the site was left as landscaping and forest. The total disturbed area of the project site is approximately 0.37 acres and includes the site as well as frontage improvements. An additional 0.04 of existing impervious road area will be collected. This area exists between the eastern boundary of the project site and centerline of existing road. See Figure 4-1 on the following pages for the predeveloped conditions exhibit. As per the flow control standard designated for the site, the project area will be modeled as Till Forest in MGS Flood. The existing road area collected in the drainage basin will be modeled as impervious in the predeveloped condition. The predeveloped areas are shown in the table below. Table 4-1 Predeveloped Conditions Ground Cover Area (SF) Area (Acres) Till Forest 16,151 0.37 Impervious 1,550 0.04 Total Basin 17,701 0.41 Predeveloped Bypass/Intercepted Mitigation Trade Areas Till Forest (SF) Impervious (SF) Total (SF) Bypass Area 560 0 560 Intercepted Off-Site Area 560 0 560 Net Change 0 0 0 4.2 Developed Site Hydrology Proposed development of the property will include the demolition of all existing structures and the construction of two single family residences, shared driveway, utilities, a detention vault, and frontage improvements along Field Avenue NE. The impervious area per lot was determined using the existing zoning of the site (R-8) and the city’s municipal code. Lot The maximum impervious coverage for a zoning of R-8 is 65% per lot. The impervious area per lot is based on max per zoning or 4,000 sf, whichever is less. A mitigation trade area is proposed for the developed condition. The target surface area onsite exists in the form of frontage north of proposed catch basin #7 (shown on exhibit). This will not be linked to the onsite vault and will be conveyed north offsite. As part of the mitigation trade, an equivalent existing non-target area between proposed catch basin #6 and the adjacent existing catch basin south of the site Core Design, Inc. HARDY SHORT PLAT Page 4-2 will be detained within the vault. The net effect of flow control will be equivalent to the condition as if the mitigation trade didn’t occur. The undetained runoff being traded does not create a significant adverse impact to downstream drainage systems. The developed conditions are shown in the table below. See Figure 4-2 on the following page for the developed conditions exhibit. No flow credits have been taken for the proposed flow control BMPs. Table 4-2 Developed Conditions Ground Cover Total Area (SF) Impervious (SF) Pervious (SF) Lot 1 7,565 4,000 3,565 Lot 2 5,264 3,422 1,842 Tract A 2,132 1,444 688 Right of Way 1,190 681 509 Existing Roadway 1,550 1,550 0 Total (SF) 17,701 11,097 6,604 Total (Acres) 0.41 0.26 0.15 Developed Bypass/Intercepted Mitigation Trade Areas Pervious (SF) Impervious (SF) Total (SF) Bypass Area 280 280 560 Intercepted Off- Site Area 0 560 560 Net Change -280 +280 0 DESIGNE N G I N E E R I N G P L A N N I N G S U R V E Y I N G12100 NE 195th St, Suite 300Bothell, Washington 98011425.885.7877 Fax 425.885.796321019 12ROWTRACT ADESIGNE N G I N E E R I N G P L A N N I N G S U R V E Y I N G12100 NE 195th St, Suite 300Bothell, Washington 98011425.885.7877 Fax 425.885.796321019 Core Design, Inc. HARDY SHORT PLAT Page 4-4 4.3 Flow Control System Using the predeveloped and developed areas above, a 44’ x 14’ vault with 6.75’ of live storage was sized. The vault requires 4,084 CF for sufficient capacity and will be designed to provide 4,084 CF. Below are the vault details and the flow rates. The full MGS Flood report can be found in Appendix A. Predevelopment Runoff Postdevelopment Runoff Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs) ---------------------------------------------------------------------------------------------------------------------- 2-Year 2.086E-02 2-Year 9.375E-03 5-Year 2.991E-02 5-Year 1.448E-02 10-Year 3.755E-02 10-Year 1.877E-02 25-Year 5.051E-02 25-Year 2.437E-02 50-Year 5.877E-02 50-Year 2.885E-02 100-Year 6.410E-02 100-Year 3.970E-02 200-Year 8.825E-02 200-Year 5.663E-02 500-Year 0.121 500-Year 7.909E-02 ** Record too Short to Compute Peak Discharge for These Recurrence Intervals **** Flow Duration Performance **** Excursion at Predeveloped 50%Q2 (Must be Less Than or Equal to 0%): -34.3% PASS Maximum Excursion from 50%Q2 to Q2 (Must be Less Than or Equal to 0%): -5.2% PASS Maximum Excursion from Q2 to Q50 (Must be less than 10%): -10.8% PASS Percent Excursion from Q2 to Q50 (Must be less than 50%): 0.0% PASS ------------------------------------------------------------------------------------------------- MEETS ALL FLOW DURATION DESIGN CRITERIA: PASS ------------------------------------------------------------------------------------------------- Core Design, Inc. HARDY SHORT PLAT Page 4-5 Link Name: Vault Link Type: Structure Downstream Link: None Prismatic Pond Option Used Pond Floor Elevation (ft) : 456.59 Riser Crest Elevation (ft) : 463.22 Max Pond Elevation (ft) : 463.72 Storage Depth (ft) : 6.63 Pond Bottom Length (ft) : 44.0 Pond Bottom Width (ft) : 14.0 Pond Side Slopes (ft/ft) : L1= 0.00 L2= 0.00 W1= 0.00 W2= 0.00 Bottom Area (sq-ft) : 616. Area at Riser Crest El (sq-ft) : 616. (acres) : 0.014 Volume at Riser Crest (cu-ft) : 4,084. (ac-ft) : 0.094 Area at Max Elevation (sq-ft) : 616. (acres) : 0.014 Vol at Max Elevation (cu-ft) : 4,392. (ac-ft) : 0.101 Hydraulic Conductivity (in/hr) : 0.00 Massmann Regression Used to Estimate Hydraulic Gradient Depth to Water Table (ft) : 100.00 Bio-Fouling Potential : Low Maintenance : Average or Better Riser Geometry Riser Structure Type : Circular Riser Diameter (in) : 12.00 Common Length (ft) : 0.000 Riser Crest Elevation : 463.22 ft Hydraulic Structure Geometry Number of Devices: 4 ---Device Number 1 --- Device Type : Circular Orifice Control Elevation (ft) : 456.59 Diameter (in) : 0.44 Orientation : Horizontal Elbow : No ---Device Number 2 --- Device Type : Circular Orifice Control Elevation (ft) : 460.30 Diameter (in) : 0.44 Orientation : Horizontal Elbow : Yes ---Device Number 3 --- Device Type : Circular Orifice Control Elevation (ft) : 461.65 Diameter (in) : 0.25 Orientation : Horizontal Elbow : Yes --- Device Number 4 --- Device Type : Circular Orifice Invert Elevation (ft) : 462.05 Length (ft) : 0.31 Orientation : Horizontal Elbow : Yes 4.4 BMP Feasibility Per Section 1.2.9.1 in the RSWDM, projects subject to Core Requirement #9 must apply on-site BMPs to either supplement the flow mitigation provided by required flow control facilities or provide flow mitigation where flow control facilities are not required. On-site BMPs must be implemented per the requirements and approach detailed in Sections 1.2.9.2 and 1.2.9.3 for individual lots and subdivisions or road improvement projects, respectively. The Section applicable to this project is Section 1.2.9.2. Per Section 1.2.9.2, projects on individual sites/lots, on-site BMPs must be selected and applied according to the individual lot BMP requirements. The project site is smaller than 22,000 square feet and follows requirements specified in Section 1.2.9.2.1 Small Lot BMP Requirements of the 2017 RSWDM. 1. The feasibility and applicability of full dispersion as detailed in Appendix C, Section C.2.1 must be evaluated for all target impervious surfaces. If feasible and applicable, full dispersion must be implemented as part of the proposed project. Typically, small lot full dispersion will be applicable only in subdivisions where enough forest was preserved by tract, easement, or covenant to meet the minimum requirements for full dispersion in Appendix C, Section C.2.1.1 Full dispersion is not feasible due to non-existent native forested area. 2. Where full dispersion of target impervious roof areas is not feasible or applicable, or will cause flooding or erosion impacts, the feasibility and applicability of full infiltration as detailed in Appendix C, Section C.2.2 must be evaluated (note, this will require a soils report for the site/lot). If feasible and applicable, full infiltration of roof runoff must be implemented as part of the proposed project. As per the Stormwater Feasibility Evaluation by Cobalt Geosciences dated January 6, 2021, “We do not recommend the use of infiltration systems at this site.” 3. All target impervious surfaces not mitigated by Requirements 1 and 2 above, must be mitigated to the maximum extent feasible using one or more BMPs from the following list. Use of a given BMP is subject to evaluation of its feasibility and applicability as detailed in Appendix C. Feasible BMPs are required to be implemented. The BMPs listed below may be located anywhere on the site/lot subject to the limitations and design specifications for each BMP. These BMPs must be implemented as part of the proposed project. • Full Infiltration per Appendix C, Section C.2.2, or per Section 5.2, whichever is applicable As per the Stormwater Feasibility Evaluation by Cobalt Geosciences dated January 6, 2021, “We do not recommend the use of infiltration systems at this site.” • Limited Infiltration per Appendix C, Section C.2.3, Per the Stormwater Feasibility Evaluation by Cobalt Geosciences dated January 6, 2021, “We do not recommend the use of infiltration systems at this site.” • Rain Gardens/Bioretention per Appendix C, Section C.2.6 and C.2.12 12 The Geotechnical Addendum indicates that raingardens/bioretention may be feasible, however due to minimum 5’ setbacks to buildings and property lines, minimum side slopes of 2.5:1 a rain garden or bioretention cell cannot be provided on either lot within the setback. • Permeable Pavement per Appendix C, Section C.2.7 For lot 1 permeable pavement is infeasible because the proposed driveway area would be subjected to heavy construction vehicles for construction of the house and stormwater vault. Permeable pavement will be provided on lot 2 and will follow the recommendations per the Stormwater Feasibility Evaluation by Cobalt Geosciences dated January 6, 2021. 4. All target impervious surfaces not mitigated by Requirements 1, 2 and 3 above, must be mitigated to the maximum extent feasible using the Basic Dispersion BMP described below. Use of Basic Dispersion is subject to evaluation of its feasibility and applicability as detailed in Appendix C. Feasible BMPs are required to be implemented. Basic Dispersion BMPs may be located anywhere on the site/lot subject to the limitations and design specifications cited in Appendix C. The BMP must be implemented as part of the proposed project. • Basic Dispersion per Appendix C, Section C.2.4, Given the setbacks and flow path requirements basic dispersion is not feasible on either lot. 5. BMPs must be implemented, at minimum, for an impervious area equal to at least 10% of the site/lot for site/lot sizes up to 11,000 square feet and at least 20% of the site/lot for site/lot sizes between 11,000 and 22,000 square feet. For projects located in Zone 1 of the Aquifer Protection Area, these impervious area amounts must be doubled. Doubling of the minimum impervious area required for BMP implementation in Zone 1 of the Aquifer Protection Area is not required for projects located within 200 feet of a steep slope hazard area, landslide hazard, or erosion hazard area. If these minimum areas are not mitigated using feasible BMPs from Requirements 1, 2, 3, and 4 above, one or more BMPs from the following list are required to be implemented to achieve compliance. These BMPs must be implemented as part of the proposed project. • Reduced Impervious Surface Credit per Appendix C, Section C.2.9, • Native Growth Retention Credit per Appendix C, Section C.2.10. A reduced impervious area surface credit of 757 square feet will be taken on lot 1 to meet the minimum BMP requirement. On lot 2, since permeable pavement will be provided a reduced impervious area surface credit of 87 square feet is will be implemented. Therefore the lots will be limited to: Lot 1: 4,000 sf – 757 sf = 3,243 sf Lot 2: 3,422 sf – 87 sf = 3,335 sf 6. The soil moisture holding capacity of new pervious surfaces (target pervious surfaces) must be protected in accordance with the soil amendment BMP as detailed in Appendix C, Section C.2.13. Soil amendment will be incorporated for disturbed areas not covered with hard surfaces. 7. Any proposed connection of roof downspouts to the local drainage system must be via a perforated pipe connection as detailed in Appendix C, Section C.2.11. One perforated pipe connection will be provided for each lot upstream of the detention vault. Table 4-3 BMP Summary Lot BMP Area (sf) BMP Area (sf) BMP Area Provided BMP Area Required 1 Reduced Impervious Credit 757 - - 757 7,565(10%) = 757 2 Permeable Pavement 439 Reduced Impervious Credit 87 526 5,264(10%) = 526 4.5 Water Quality Treatment Analysis and Design The building footprints for the lots have not yet been determined, therefore the driveway area may vary. However, the project will assume a driveway area of 800 SF each to be conservative. A leachable materials covenant is being submitted with the Civil Construction permit. Therefore, roof areas will not count towards PGIS.. The subject project does not exceed 5,000 SF of PGIS, therefore basic water quality treatment is not required. See Table 4-3 below for an area breakdown. Table 4-4 PGIS Areas Ground Cover Area (SF) Shared Driveway Access 1,601 Lot Driveway 1,600 Total Area 3,201 Core Design, Inc. HARDY SHORT PLAT Page 5-1 5. DOWNSTREAM CONVEYANCE SYSTEM CAPACITY ANALYSIS The rational method was implemented to design the conveyance system for flows upstream of the detention vault. Per the 2017 RSWDM, 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. The new system was designed for the 25-year, 24-hour, and 100-year, 24-hour storm events. A conveyance spreadsheet was generated using the rational method to calculate flows for the area collected by each catch basin. The precipitation rates for the 25-year, 24-hour, and 100-year, 24-hour storm events are 3.4 inches and 3.94 inches respectively. The flows generated from the conveyance system spreadsheets for both storm events were input to backwater analysis spreadsheets to confirm adequate sizing. The backwater analysis was performed to ensure that during the 25-year, 24-hour storm event, the headwater elevation in each structure did not overtop any of the rims. For the 100-year, 24-hour storm event, structures are allowed to overtop, but all runoff must be safely conveyed to ensure that overflowing runoff or ponding would not cause structural damage. Weighted C values were used in the rational method spreadsheet. Impervious area has a C value of 0.9 and grass area has a C value of 0.25. These values along with the impervious area and grass area of the developed basin were used to calculate the weighted C value. See calculations provided below. ((0.81 x 0.25) + (1.32 x 0.9))/2.13 = 0.65 = C The tailwater elevations within the vault were derived from the MGS Flood sizing analysis. See the MGS Flood generated reports provided in Section 4. Tailwater elevations for the 25-year storm event and the 100-year storm event for the East and West basins area provided in the table below. Storm Event Year Tailwater Elevation 25-year 464.82 100-year 465.12 During the 25-year storm all headwater elevations remained below the rim elevations of all catch basins. During the 100-year storm all headwater elevations also remained below the rim elevations of all catch basins for both the conveyance upstream and downstream of the vault. See conveyance and backwater spreadsheets for the 25 and 100-year storms below. A conveyance exhibit is provided below showing the area assumed to drain to each catch basin on the following pages. For the conveyance system downstream of the vault the 100-year undetained 15-min flows from MGSFlood of 0.36 cfs from Appendix A was used as the peak flow. DESIGNE N G I N E E R I N G P L A N N I N G S U R V E Y I N G12100 NE 195th St, Suite 300Bothell, Washington 98011425.885.7877 Fax 425.885.796321019 RATIONAL METHOD CONVEYANCE SYSTEM DESIGN LOCATION: KING COUNTY PR (24-HR RAINFALL):3.4 INCHES PROJECT NAME: HARDY SHORT PLAT PROJECT NUMBER: 21019 PREPARED BY: CRV DESIGN STORM: 25 YEAR SUBBASIN PIPE PIPE PIPE ACTUAL TRAVEL PIPE CAPACITY SUMMARY LOCATION AREA SUM OF Tc IR QR MANNING'S SIZE SLOPE LENGTH VELOCITY (VR)TIME Q(FULL) V(FULL)QR/Q(FULL) FROM TO (AC) "C" (A * C) (A * C) (MIN) (IN/HR) (CFS) "n" (IN) (%) (FT) (FT/SEC) (MIN) (CFS) (FT/SEC) (%) 6 5 0.060 0.65 0.039 0.039 6.30 2.73 0.107 0.012 12 5.000 100 3.35 0.50 8.631 10.99 1.2% 5 Vault 0.350 0.65 0.228 0.267 6.80 2.60 0.693 0.012 12 33.330 6 12.20 0.01 22.283 28.37 3.1% RATIONAL METHOD CONVEYANCE SYSTEM DESIGN LOCATION: KING COUNTY PR (24-HR RAINFALL):3.94 INCHES PROJECT NAME: HARDY SHORT PLAT PROJECT NUMBER: 21019 PREPARED BY: CRV DESIGN STORM: 100 YEAR SUBBASIN PIPE PIPE PIPE ACTUAL TRAVEL PIPE CAPACITY SUMMARY LOCATION AREA SUM OF Tc IR QR MANNING'S SIZE SLOPE LENGTH VELOCITY (VR)TIME Q(FULL) V(FULL)QR/Q(FULL) FROM TO (AC) "C" (A * C) (A * C) (MIN) (IN/HR) (CFS) "n" (IN) (%) (FT) (FT/SEC) (MIN) (CFS) (FT/SEC) (%) 6 5 0.060 0.65 0.039 0.039 6.30 3.23 0.126 0.012 12 5.000 100 3.35 0.50 8.631 10.99 1.5% 5 Vault 0.350 0.65 0.228 0.267 6.80 3.07 0.819 0.012 12 33.330 6 12.20 0.01 22.283 28.37 3.7% BACKWATER CALCULATIONS PROJECT NAME: Hardy Short Plat PREPARED BY: CRV PROJECT NUMBER: 21019 DESIGN STORM: 25 YEAR ENTRANCE ENTRANCE EXIT OUTLET INLET APPROACH BEND JUNCTION PIPE PIPE MANNING'S OUTLET INLET PIPE FULL VELOCITY TAILWATER FRICTION HGL HEAD HEAD CONTROL CONTROL VELOCITY HEAD HEAD HEADWATER RIM FROM TO Q LENGTH SIZE "n" ELEVATION ELEVATION AREA VELOCITY HEAD ELEVATION LOSS ELEVATION LOSS LOSS ELEVATION ELEVATION HEAD LOSS LOSS ELEVATION ELEVATION FREEBOARD CB CB (CFS) (FT) (IN) VALUE (FT) (FT) (SQ FT) (FT/SEC) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) Vault 5 0.69 6 12 0.012 461.00 463.00 0.79 0.88 0.01 464.82 0.00 464.82 0.01 0.01 464.84 464.00 0.00 0.00 0.00 464.84 467.92 3.08 5 6 0.11 100 12 0.012 463.00 468.00 0.79 0.14 0.00 464.84 0.00 469.00 0.00 0.00 469.00 469.00 0.00 0.00 0.00 469.00 472.00 3.00 PIPE SEGMENT BACKWATER CALCULATIONS PROJECT NAME: Hardy Short Plat PREPARED BY: CRV PROJECT NUMBER: 210119 DESIGN STORM: 100 YEAR ENTRANCE ENTRANCE EXIT OUTLET INLET APPROACH BEND JUNCTION PIPE PIPE MANNING'S OUTLET INLET PIPE FULL VELOCITY TAILWATER FRICTION HGL HEAD HEAD CONTROL CONTROL VELOCITY HEAD HEAD HEADWATER RIM FROM TO Q LENGTH SIZE "n" ELEVATION ELEVATION AREA VELOCITY HEAD ELEVATION LOSS ELEVATION LOSS LOSS ELEVATION ELEVATION HEAD LOSS LOSS ELEVATION ELEVATION FREEBOARD CB CB (CFS) (FT) (IN) VALUE (FT) (FT) (SQ FT) (FT/SEC) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) Vault 5 0.82 6 12 0.012 461.00 463.00 0.79 1.04 0.02 465.12 0.00 465.12 0.01 0.02 465.15 464.00 0.00 0.00 0.00 465.15 467.92 2.77 5 6 0.13 100 12 0.012 463.00 468.00 0.79 0.16 0.00 465.15 0.00 469.00 0.00 0.00 469.00 469.00 0.00 0.00 0.00 469.00 472.00 3.00 CB2 CB3 0.36 97 12 0.012 455.32 455.90 0.79 0.46 0.00 456.32 0.01 456.90 0.00 0.00 456.90 456.90 0.00 0.00 0.00 456.90 462.06 5.16 CB3 CB4 0.36 73 12 0.012 455.90 456.34 0.79 0.46 0.00 456.90 0.01 457.34 0.00 0.00 457.34 457.34 0.00 0.00 0.00 457.34 462.16 4.82 CB4 VAULT OUT 0.36 38 12 0.012 456.34 456.59 0.79 0.46 0.00 457.34 0.00 457.59 0.00 0.00 457.59 457.59 0.00 0.00 0.00 457.59 463.72 6.13 PIPE SEGMENT Core Design, Inc. HARDY SHORT PLAT Page 6-1 6. SPECIAL REPORTS AND STUDIES The following reports and assessments are provided for reference and informational purposes only. Core Design takes no responsibility or liability for these reports, assessments or designs as they were not completed under the direct supervision of Core Design.  Stormwater Feasibility Evaluation January 6, 2021 Cobalt Geosciences, LLC P.O Box 82243 Kenmore, WA 98028 206-331-1097  Geotechnical Addendum November 22, 2021 Cobalt Geosciences, LLC P.O Box 82243 Kenmore, WA 98028 206-331-1097 Core Design, Inc. HARDY SHORT PLAT Page 7-1 7. OTHER PERMITS  Utilities Permit  Building Permits  ROW Use Permit Core Design, Inc. HARDY SHORT PLAT Page 8-1 8. ESC ANALYSIS AND DESIGN ESC Plan Analysis and Design (Part A) 1. The site will utilize Appendix D of the 2017 RSWDM for the erosion and sedimentation control design to reduce the discharge of sediment-laden runoff from the site. Clearing limits will be established prior to any earthwork on the project site. Perimeter protection will be provided by silt fencing along the entire perimeter of the site to limit the downstream transport of sediment to the neighboring properties. Dust control, if required, will be provided by a water truck. A Certified Erosion and Sediment Control Lead inspector will be present onsite during earthwork activities. The inspector shall determine frequency of watering of the project site and will authorize and direct any additional erosion and sediment control measures as needed during all construction activities. The plan will be comprised of temporary measures (stabilized construction entrance, silt fence, and inlet protection). 2. Due to the size of the project, no sediment control facilities like a sediment trap are proposed. 3. There are no areas on site with a particularly high susceptibility to erosion. Catch basin inserts are proposed for all proposed stormwater structures. 4. There are no erosion and sediment control recommendations in the infiltration feasibility or arborist reports. 5. The project is proposing to use the existing asphalt driveway as a construction entrance. SWPPS Plan Design (Part B) The following pollution control measures shall be implemented as applicable using activity specific BMPs detailed in Section D.2.2 (and Section D.2.1 as applicable) of Appendix D and the King County Stormwater Pollution Prevention Manual (SPPM). The receiving water for this project is the Cedar River. 1. All pollutants, including waste materials, that occur onsite shall be handled and disposed of in a manner that does not cause contamination of stormwater 2. Chemicals, liquid products, petroleum products, and non-inert wastes are not anticipated on site. 3. Maintenance and repair of heavy equipment and vehicles involving oil changes, hydraulic system drain down, solvent and de-greasing cleaning operations, fuel tank drain down and removal, and other activities which may result in discharge or spillage of pollutants to the ground or into stormwater runoff are not anticipated on site. Core Design, Inc. HARDY SHORT PLAT Page 8-2 4. Application of agricultural chemicals, including fertilizers and pesticides, shall be conducted in a manner and at application rates that will not result in loss of chemical to stormwater runoff. Manufacturers' recommendations for application rates and procedures shall be followed. 5. Stormwater discharges shall not cause or contribute to a violation of the water quality standard for pH in the receiving water. Measures shall be used to prevent or treat contamination of stormwater runoff by pH modifying sources. These sources include, but are not limited to: a. bulk cement b. cement kiln dust, fly ash c. new concrete washing and curing waters d. waste streams generated from concrete grinding and sawing e. exposed aggregate processes, and concrete pumping and mixer washout 6. For full compliance with KCC 9.12 Water Quality, the project may need to include measures for the permanent structures and features constructed under other permits. See the Stormwater Pollution Prevention Manual (SPPM) for Activity Sheets describing issues and measures to address them. Common issues include: a. Containment area planning for storage of liquid materials in stationary or portable tanks, storage of solid waste and food wastes including cooking grease, are not anticipated for this site. b. Permanent canopy and paving requirements for permanent outdoor vehicle parking, maintenance and storage areas are not anticipated for this site. Core Design, Inc. HARDY SHORT PLAT Page 9-1 9. BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT 9.1 Bond Quantities A Site Improvement Bond Quantity Worksheet is provided at the end of this section. 9.2 Facility Summaries A Facility Summary Sheet is provided at the end of this section. 9.3 Declaration of Covenant A Declaration of Covenant for the private detention vault has been submitted with the Civil Construction Permit. The covenant for the individual flow control BMPs on each lot will be submitted with the building permits. 1055 South Grady Way – 6 th Floor | Renton, WA 98057 (425) 430-7200 Date Prepared: Name: PE Registration No: Firm Name: Firm Address: Phone No. Email Address: Project Name: Project Owner: CED Plan # (LUA):Phone: CED Permit # (C):Address: Site Address: Street Intersection:Addt'l Project Owner: Parcel #(s):Phone: Address: Clearing and grading greater than or equal to 5,000 board feet of timber? Yes/No:NO Water Service Provided by: If Yes, Provide Forest Practice Permit #:Sewer Service Provided by: Abbreviated Legal Description: SE1/4, NW1/4, SEC. 10, TWP. 23 N., RGE. 5 E., W.M. 857 Field Avenue NE PO Box 2170,######## 21-000169 206.714.6707 1/26/2022 Prepared by: FOR APPROVALProject Phase 1 shm@coredesigninc.com Sheri Murata 41846 Core Design Inc. 12100 NE 195th St, Suite #300, Bothell, WA 98011 425.885.7877 SITE IMPROVEMENT BOND QUANTITY WORKSHEET PROJECT INFORMATION KC WATER DISTRICT 90 CITY OF RENTON Engineer Stamp Required (all cost estimates must have original wet stamp and signature) Clearing and Grading Utility Providers N/A Project Location and Description Project Owner Information Hardy Short Plat Renton, WA 98056 1437650040 Andrew Michael Construction, LLC Page 1 of 14 Ref 8-H Bond Quantity Worksheet SECTION I PROJECT INFORMATION Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 10.1% Total Estimated Construction Costs E A + B + C + D 217,050.97$ Estimated Civil Construction Permit - Construction Costs2 Stormwater (Erosion Control + Drainage)C 102,583.47$ As outlined in City Ordinance No. 4345, 50% of the plan review and inspection fees are to be paid at Permit Submittal. The balance is due at Permit Issuance. Significant changes or additional review cycles (beyond 3 cycles) during the review process may result in adjustments to the final review fees. Roadway (Transportation)D 64,063.72$ Water A -$ Wastewater (Sanitary Sewer)B 50,403.78$ 2 All prices include labor, equipment, materials, overhead, profit, and taxes. City of Renton Sales Tax is: 1 Select the current project status/phase from the following options: For Approval - Preliminary Data Enclosed, pending approval from the City; For Construction - Estimated Data Enclosed, Plans have been approved for contruction by the City; Project Closeout - Final Costs and Quantities Enclosed for Project Close-out Submittal Page 2 of 14 Ref 8-H Bond Quantity Worksheet SECTION I PROJECT INFORMATION Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Unit Reference #Price Unit Quantity Cost Backfill & compaction-embankment ESC-1 7.50$ CY Check dams, 4" minus rock ESC-2 SWDM 5.4.6.3 90.00$ Each Catch Basin Protection ESC-3 145.00$ Each 4 580.00 Crushed surfacing 1 1/4" minus ESC-4 WSDOT 9-03.9(3)110.00$ CY Ditching ESC-5 10.50$ CY Excavation-bulk ESC-6 2.30$ CY 250 575.00 Fence, silt ESC-7 SWDM 5.4.3.1 5.00$ LF 464 2,320.00 Fence, Temporary (NGPE)ESC-8 1.75$ LF Geotextile Fabric ESC-9 3.00$ SY Hay Bale Silt Trap ESC-10 0.60$ Each Hydroseeding ESC-11 SWDM 5.4.2.4 0.90$ SY Interceptor Swale / Dike ESC-12 1.15$ LF Jute Mesh ESC-13 SWDM 5.4.2.2 4.00$ SY Level Spreader ESC-14 2.00$ LF Mulch, by hand, straw, 3" deep ESC-15 SWDM 5.4.2.1 2.90$ SY Mulch, by machine, straw, 2" deep ESC-16 SWDM 5.4.2.1 2.30$ SY Piping, temporary, CPP, 6"ESC-17 13.75$ LF Piping, temporary, CPP, 8"ESC-18 16.00$ LF Piping, temporary, CPP, 12"ESC-19 20.50$ LF Plastic covering, 6mm thick, sandbagged ESC-20 SWDM 5.4.2.3 4.60$ SY Rip Rap, machine placed; slopes ESC-21 WSDOT 9-13.1(2)51.00$ CY Rock Construction Entrance, 50'x15'x1'ESC-22 SWDM 5.4.4.1 2,050.00$ Each Rock Construction Entrance, 100'x15'x1'ESC-23 SWDM 5.4.4.1 3,675.00$ Each Sediment pond riser assembly ESC-24 SWDM 5.4.5.2 2,525.00$ Each Sediment trap, 5' high berm ESC-25 SWDM 5.4.5.1 22.00$ LF Sed. trap, 5' high, riprapped spillway berm section ESC-26 SWDM 5.4.5.1 80.00$ LF Seeding, by hand ESC-27 SWDM 5.4.2.4 1.15$ SY Sodding, 1" deep, level ground ESC-28 SWDM 5.4.2.5 9.20$ SY Sodding, 1" deep, sloped ground ESC-29 SWDM 5.4.2.5 11.50$ SY TESC Supervisor ESC-30 125.00$ HR 4 500.00 Water truck, dust control ESC-31 SWDM 5.4.7 160.00$ HR Unit Reference #Price Unit Quantity Cost 8.00$ LF 110 880.00 EROSION/SEDIMENT SUBTOTAL:4,855.00 SALES TAX @ 10.1%490.36 EROSION/SEDIMENT TOTAL:5,345.36 (A) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR EROSION & SEDIMENT CONTROL Description No. (A) Tree Protection Fence WRITE-IN-ITEMS Page 3 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.a EROSION_CONTROL Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost GENERAL ITEMS Backfill & Compaction- embankment GI-1 7.00$ CY Backfill & Compaction- trench GI-2 10.25$ CY Clear/Remove Brush, by hand (SY)GI-3 1.15$ SY Bollards - fixed GI-4 275.00$ Each Bollards - removable GI-5 520.00$ Each Clearing/Grubbing/Tree Removal GI-6 11,475.00$ Acre 0.34 3,901.50 Excavation - bulk GI-7 2.30$ CY 90 207.00 Excavation - Trench GI-8 5.75$ CY 200 1,150.00 Fencing, cedar, 6' high GI-9 23.00$ LF Fencing, chain link, 4'GI-10 44.00$ LF Fencing, chain link, vinyl coated, 6' high GI-11 23.00$ LF Fencing, chain link, gate, vinyl coated, 20' GI-12 1,600.00$ Each Fill & compact - common barrow GI-13 28.75$ CY 340 9,775.00 Fill & compact - gravel base GI-14 31.00$ CY Fill & compact - screened topsoil GI-15 44.75$ CY Gabion, 12" deep, stone filled mesh GI-16 74.50$ SY Gabion, 18" deep, stone filled mesh GI-17 103.25$ SY Gabion, 36" deep, stone filled mesh GI-18 172.00$ SY Grading, fine, by hand GI-19 2.90$ SY Grading, fine, with grader GI-20 2.30$ SY 100 230.00 1662 3,822.60 Monuments, 3' Long GI-21 1,025.00$ Each Sensitive Areas Sign GI-22 8.00$ Each Sodding, 1" deep, sloped ground GI-23 9.25$ SY Surveying, line & grade GI-24 975.00$ Day 0.5 487.50 0.5 487.50 Surveying, lot location/lines GI-25 2,050.00$ Acre 0.41 840.50 Topsoil Type A (imported)GI-26 32.75$ CY 70 2,292.50 Traffic control crew ( 2 flaggers )GI-27 137.75$ HR 4 551.00 Trail, 4" chipped wood GI-28 9.15$ SY Trail, 4" crushed cinder GI-29 10.25$ SY Trail, 4" top course GI-30 13.75$ SY Conduit, 2"GI-31 5.75$ LF Wall, retaining, concrete GI-32 63.00$ SF Wall, rockery GI-33 17.25$ SF SUBTOTAL THIS PAGE:1,931.00 2,780.00 19,034.10 (B)(C)(D)(E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR STREET AND SITE IMPROVEMENTS Quantity Remaining (Bond Reduction) (B)(C) Page 4 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.b TRANSPORTATION Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR STREET AND SITE IMPROVEMENTS Quantity Remaining (Bond Reduction) (B)(C) ROAD IMPROVEMENT/PAVEMENT/SURFACING AC Grinding, 4' wide machine < 1000sy RI-1 34.50$ SY AC Grinding, 4' wide machine 1000-2000sy RI-2 18.25$ SY AC Grinding, 4' wide machine > 2000sy RI-3 11.50$ SY AC Removal/Disposal RI-4 40.00$ SY 122 4,880.00 Barricade, Type III ( Permanent )RI-5 64.25$ LF Guard Rail RI-6 34.50$ LF Curb & Gutter, rolled RI-7 19.50$ LF Curb & Gutter, vertical RI-8 14.25$ LF 85 1,211.25 87 1,239.75 Curb and Gutter, demolition and disposal RI-9 20.50$ LF 85 1,742.50 Curb, extruded asphalt RI-10 6.25$ LF Curb, extruded concrete RI-11 8.00$ LF Sawcut, asphalt, 3" depth RI-12 3.00$ LF 432 1,296.00 Sawcut, concrete, per 1" depth RI-13 5.00$ LF Sealant, asphalt RI-14 2.25$ LF 432 972.00 Shoulder, gravel, 4" thick RI-15 17.25$ SY Sidewalk, 4" thick RI-16 43.50$ SY 33 1,435.50 15 652.50 Sidewalk, 4" thick, demolition and disposal RI-17 37.00$ SY Sidewalk, 5" thick RI-18 47.00$ SY 9 423.00 Sidewalk, 5" thick, demolition and disposal RI-19 46.00$ SY Sign, Handicap RI-20 97.00$ Each Striping, per stall RI-21 8.00$ Each Striping, thermoplastic, ( for crosswalk )RI-22 3.50$ SF Striping, 4" reflectorized line RI-23 0.55$ LF Additional 2.5" Crushed Surfacing RI-24 4.15$ SY HMA 1/2" Overlay 1.5" RI-25 16.00$ SY HMA 1/2" Overlay 2"RI-26 20.75$ SY 310 6,432.50 HMA Road, 2", 4" rock, First 2500 SY RI-27 32.25$ SY 155 4,998.75 HMA Road, 2", 4" rock, Qty. over 2500SY RI-28 24.00$ SY HMA Road, 4", 6" rock, First 2500 SY RI-29 51.75$ SY HMA Road, 4", 6" rock, Qty. over 2500 SY RI-30 42.50$ SY HMA Road, 4", 4.5" ATB RI-31 43.50$ SY Gravel Road, 4" rock, First 2500 SY RI-32 17.25$ SY Gravel Road, 4" rock, Qty. over 2500 SY RI-33 11.50$ SY Thickened Edge RI-34 10.00$ LF SUBTOTAL THIS PAGE:11,960.25 652.50 12,671.00 (B)(C)(D)(E) Page 5 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.b TRANSPORTATION Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR STREET AND SITE IMPROVEMENTS Quantity Remaining (Bond Reduction) (B)(C) PARKING LOT SURFACING No. 2" AC, 2" top course rock & 4" borrow PL-1 24.00$ SY 2" AC, 1.5" top course & 2.5" base course PL-2 32.00$ SY 4" select borrow PL-3 5.75$ SY 1.5" top course rock & 2.5" base course PL-4 16.00$ SY SUBTOTAL PARKING LOT SURFACING: (B)(C)(D)(E) LANDSCAPING & VEGETATION No. Street Trees LA-1 220.00$ EA 2 440.00 Median Landscaping LA-2 45.00$ SY 76 3,420.00 Right-of-Way Landscaping LA-3 45.00$ SY 48 2,160.00 Wetland Landscaping LA-4 SUBTOTAL LANDSCAPING & VEGETATION:2,600.00 3,420.00 (B)(C)(D)(E) TRAFFIC & LIGHTING No. Signs TR-1 Street Light System ( # of Poles)TR-2 Traffic Signal TR-3 Traffic Signal Modification TR-4 SUBTOTAL TRAFFIC & LIGHTING: (B)(C)(D)(E) WRITE-IN-ITEMS Driveway Approach 36.00$ LF 16 576.00 AC Pavement Patching 21.00$ SY 122 2,562.00 SUBTOTAL WRITE-IN ITEMS:3,138.00 STREET AND SITE IMPROVEMENTS SUBTOTAL:19,629.25 3,432.50 35,125.10 SALES TAX @ 10.1%1,982.55 346.68 3,547.64 STREET AND SITE IMPROVEMENTS TOTAL:21,611.80 3,779.18 38,672.74 (B)(C)(D)(E) Page 6 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.b TRANSPORTATION Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost DRAINAGE (CPE = Corrugated Polyethylene Pipe, N12 or Equivalent) For Culvert prices, Average of 4' cover was assumed. Assume perforated PVC is same price as solid pipe.) Access Road, R/D D-1 30.00$ SY * (CBs include frame and lid) Beehive D-2 103.00$ Each Through-curb Inlet Framework D-3 460.00$ Each CB Type I D-4 1,725.00$ Each 2 3,450.00 2 3,450.00 CB Type IL D-5 2,000.00$ Each CB Type II, 48" diameter D-6 3,500.00$ Each 1 3,500.00 2 7,000.00 for additional depth over 4' D-7 550.00$ FT 4 2,200.00 CB Type II, 54" diameter D-8 4,075.00$ Each for additional depth over 4'D-9 570.00$ FT CB Type II, 60" diameter D-10 4,225.00$ Each for additional depth over 4'D-11 690.00$ FT CB Type II, 72" diameter D-12 6,900.00$ Each for additional depth over 4'D-13 975.00$ FT CB Type II, 96" diameter D-14 16,000.00$ Each for additional depth over 4'D-15 1,050.00$ FT Trash Rack, 12"D-16 400.00$ Each Trash Rack, 15"D-17 470.00$ Each Trash Rack, 18"D-18 550.00$ Each Trash Rack, 21"D-19 630.00$ Each Cleanout, PVC, 4"D-20 170.00$ Each Cleanout, PVC, 6"D-21 195.00$ Each Cleanout, PVC, 8"D-22 230.00$ Each Culvert, PVC, 4" D-23 11.50$ LF Culvert, PVC, 6" D-24 15.00$ LF 30 450.00 Culvert, PVC, 8" D-25 17.00$ LF Culvert, PVC, 12" D-26 26.00$ LF 318 8,268.00 Culvert, PVC, 15" D-27 40.00$ LF Culvert, PVC, 18" D-28 47.00$ LF Culvert, PVC, 24"D-29 65.00$ LF Culvert, PVC, 30" D-30 90.00$ LF Culvert, PVC, 36" D-31 150.00$ LF Culvert, CMP, 8"D-32 22.00$ LF Culvert, CMP, 12"D-33 33.00$ LF SUBTOTAL THIS PAGE:6,950.00 21,368.00 (B)(C)(D)(E) Quantity Remaining (Bond Reduction) (B)(C) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Page 7 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Quantity Remaining (Bond Reduction) (B)(C) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES DRAINAGE (Continued) Culvert, CMP, 15"D-34 40.00$ LF Culvert, CMP, 18"D-35 47.00$ LF Culvert, CMP, 24"D-36 64.00$ LF Culvert, CMP, 30"D-37 90.00$ LF Culvert, CMP, 36"D-38 150.00$ LF Culvert, CMP, 48"D-39 218.00$ LF Culvert, CMP, 60"D-40 310.00$ LF Culvert, CMP, 72"D-41 400.00$ LF Culvert, Concrete, 8"D-42 48.00$ LF Culvert, Concrete, 12"D-43 55.00$ LF Culvert, Concrete, 15"D-44 89.00$ LF Culvert, Concrete, 18"D-45 100.00$ LF Culvert, Concrete, 24"D-46 120.00$ LF Culvert, Concrete, 30"D-47 145.00$ LF Culvert, Concrete, 36"D-48 175.00$ LF Culvert, Concrete, 42"D-49 200.00$ LF Culvert, Concrete, 48"D-50 235.00$ LF Culvert, CPE Triple Wall, 6" D-51 16.00$ LF Culvert, CPE Triple Wall, 8" D-52 18.00$ LF Culvert, CPE Triple Wall, 12" D-53 27.00$ LF Culvert, CPE Triple Wall, 15" D-54 40.00$ LF Culvert, CPE Triple Wall, 18" D-55 47.00$ LF Culvert, CPE Triple Wall, 24" D-56 64.00$ LF Culvert, CPE Triple Wall, 30" D-57 90.00$ LF Culvert, CPE Triple Wall, 36" D-58 149.00$ LF Culvert, LCPE, 6"D-59 69.00$ LF Culvert, LCPE, 8"D-60 83.00$ LF Culvert, LCPE, 12"D-61 96.00$ LF Culvert, LCPE, 15"D-62 110.00$ LF Culvert, LCPE, 18"D-63 124.00$ LF Culvert, LCPE, 24"D-64 138.00$ LF Culvert, LCPE, 30"D-65 151.00$ LF Culvert, LCPE, 36"D-66 165.00$ LF Culvert, LCPE, 48"D-67 179.00$ LF Culvert, LCPE, 54"D-68 193.00$ LF SUBTOTAL THIS PAGE: (B)(C)(D)(E) Page 8 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Quantity Remaining (Bond Reduction) (B)(C) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES DRAINAGE (Continued) Culvert, LCPE, 60"D-69 206.00$ LF Culvert, LCPE, 72"D-70 220.00$ LF Culvert, HDPE, 6"D-71 48.00$ LF Culvert, HDPE, 8"D-72 60.00$ LF Culvert, HDPE, 12"D-73 85.00$ LF Culvert, HDPE, 15"D-74 122.00$ LF Culvert, HDPE, 18"D-75 158.00$ LF Culvert, HDPE, 24"D-76 254.00$ LF Culvert, HDPE, 30"D-77 317.00$ LF Culvert, HDPE, 36"D-78 380.00$ LF Culvert, HDPE, 48"D-79 443.00$ LF Culvert, HDPE, 54"D-80 506.00$ LF Culvert, HDPE, 60"D-81 570.00$ LF Culvert, HDPE, 72"D-82 632.00$ LF Pipe, Polypropylene, 6"D-83 96.00$ LF Pipe, Polypropylene, 8"D-84 100.00$ LF Pipe, Polypropylene, 12"D-85 100.00$ LF Pipe, Polypropylene, 15"D-86 103.00$ LF Pipe, Polypropylene, 18"D-87 106.00$ LF Pipe, Polypropylene, 24"D-88 119.00$ LF Pipe, Polypropylene, 30"D-89 136.00$ LF Pipe, Polypropylene, 36"D-90 185.00$ LF Pipe, Polypropylene, 48"D-91 260.00$ LF Pipe, Polypropylene, 54"D-92 381.00$ LF Pipe, Polypropylene, 60"D-93 504.00$ LF Pipe, Polypropylene, 72"D-94 625.00$ LF Culvert, DI, 6"D-95 70.00$ LF Culvert, DI, 8"D-96 101.00$ LF Culvert, DI, 12"D-97 121.00$ LF Culvert, DI, 15"D-98 148.00$ LF Culvert, DI, 18"D-99 175.00$ LF Culvert, DI, 24"D-100 200.00$ LF Culvert, DI, 30"D-101 227.00$ LF Culvert, DI, 36"D-102 252.00$ LF Culvert, DI, 48"D-103 279.00$ LF Culvert, DI, 54"D-104 305.00$ LF Culvert, DI, 60"D-105 331.00$ LF Culvert, DI, 72"D-106 357.00$ LF SUBTOTAL THIS PAGE: (B)(C)(D)(E) Page 9 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Quantity Remaining (Bond Reduction) (B)(C) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES Specialty Drainage Items Ditching SD-1 10.90$ CY Flow Dispersal Trench (1,436 base+)SD-3 32.00$ LF French Drain (3' depth)SD-4 30.00$ LF Geotextile, laid in trench, polypropylene SD-5 3.40$ SY Mid-tank Access Riser, 48" dia, 6' deep SD-6 2,300.00$ Each Pond Overflow Spillway SD-7 18.25$ SY Restrictor/Oil Separator, 12"SD-8 1,320.00$ Each Restrictor/Oil Separator, 15"SD-9 1,550.00$ Each Restrictor/Oil Separator, 18"SD-10 1,950.00$ Each Riprap, placed SD-11 48.20$ CY Tank End Reducer (36" diameter)SD-12 1,375.00$ Each Infiltration pond testing SD-13 143.00$ HR Permeable Pavement SD-14 Permeable Concrete Sidewalk SD-15 Culvert, Box __ ft x __ ft SD-16 SUBTOTAL SPECIALTY DRAINAGE ITEMS: (B)(C)(D)(E) STORMWATER FACILITIES (Include Flow Control and Water Quality Facility Summary Sheet and Sketch) Detention Pond SF-1 Each Detention Tank SF-2 Each Detention Vault SF-3 60,000.00$ Each 1 60,000.00 Infiltration Pond SF-4 Each Infiltration Tank SF-5 Each Infiltration Vault SF-6 Each Infiltration Trenches SF-7 Each Basic Biofiltration Swale SF-8 Each Wet Biofiltration Swale SF-9 Each Wetpond SF-10 Each Wetvault SF-11 Each Sand Filter SF-12 Each Sand Filter Vault SF-13 Each Linear Sand Filter SF-14 Each Proprietary Facility SF-15 Each Bioretention Facility SF-16 Each SUBTOTAL STORMWATER FACILITIES:60,000.00 (B)(C)(D)(E) Page 10 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Quantity Remaining (Bond Reduction) (B)(C) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR DRAINAGE AND STORMWATER FACILITIES WRITE-IN-ITEMS (INCLUDE ON-SITE BMPs) WI-1 WI-2 WI-3 WI-4 WI-5 WI-6 WI-7 WI-8 WI-9 WI-10 WI-11 WI-12 WI-13 WI-14 WI-15 SUBTOTAL WRITE-IN ITEMS: DRAINAGE AND STORMWATER FACILITIES SUBTOTAL:6,950.00 81,368.00 SALES TAX @ 10.1%701.95 8,218.17 DRAINAGE AND STORMWATER FACILITIES TOTAL:7,651.95 89,586.17 (B) (C) (D) (E) Page 11 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.c DRAINAGE Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Connection to Existing Watermain W-1 3,400.00$ Each Ductile Iron Watermain, CL 52, 4 Inch Diameter W-2 58.00$ LF Ductile Iron Watermain, CL 52, 6 Inch Diameter W-3 65.00$ LF Ductile Iron Watermain, CL 52, 8 Inch Diameter W-4 75.00$ LF Ductile Iron Watermain, CL 52, 10 Inch Diameter W-5 80.00$ LF Ductile Iron Watermain, CL 52, 12 Inch Diameter W-6 145.00$ LF Gate Valve, 4 inch Diameter W-7 1,225.00$ Each Gate Valve, 6 inch Diameter W-8 1,350.00$ Each Gate Valve, 8 Inch Diameter W-9 1,550.00$ Each Gate Valve, 10 Inch Diameter W-10 2,100.00$ Each Gate Valve, 12 Inch Diameter W-11 2,500.00$ Each Fire Hydrant Assembly W-12 5,000.00$ Each Permanent Blow-Off Assembly W-13 1,950.00$ Each Air-Vac Assembly, 2-Inch Diameter W-14 3,050.00$ Each Air-Vac Assembly, 1-Inch Diameter W-15 1,725.00$ Each Compound Meter Assembly 3-inch Diameter W-16 9,200.00$ Each Compound Meter Assembly 4-inch Diameter W-17 10,500.00$ Each Compound Meter Assembly 6-inch Diameter W-18 11,500.00$ Each Pressure Reducing Valve Station 8-inch to 10-inch W-19 23,000.00$ Each WATER SUBTOTAL: SALES TAX @ 10.1% WATER TOTAL: (B) (C) (D) (E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR WATER Quantity Remaining (Bond Reduction) (B)(C) Page 12 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.d WATER Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 CED Permit #:######## Existing Future Public Private Right-of-Way Improvements Improvements (D) (E) Description No. Unit Price Unit Quant.Cost Quant.Cost Quant.Cost Quant.Cost Clean Outs SS-1 1,150.00$ Each 3 3,450.00 Grease Interceptor, 500 gallon SS-2 9,200.00$ Each Grease Interceptor, 1000 gallon SS-3 11,500.00$ Each Grease Interceptor, 1500 gallon SS-4 17,200.00$ Each Side Sewer Pipe, PVC. 4 Inch Diameter SS-5 92.00$ LF Side Sewer Pipe, PVC. 6 Inch Diameter SS-6 110.00$ LF 189 20,790.00 Sewer Pipe, PVC, 8 inch Diameter SS-7 120.00$ LF 122 14,640.00 Sewer Pipe, PVC, 12 Inch Diameter SS-8 144.00$ LF Sewer Pipe, DI, 8 inch Diameter SS-9 130.00$ LF Sewer Pipe, DI, 12 Inch Diameter SS-10 150.00$ LF Manhole, 48 Inch Diameter SS-11 6,900.00$ Each 1 6,900.00 Manhole, 54 Inch Diameter SS-13 6,800.00$ Each Manhole, 60 Inch Diameter SS-15 7,600.00$ Each Manhole, 72 Inch Diameter SS-17 10,600.00$ Each Manhole, 96 Inch Diameter SS-19 16,000.00$ Each Pipe, C-900, 12 Inch Diameter SS-21 205.00$ LF Outside Drop SS-24 1,700.00$ LS Inside Drop SS-25 1,150.00$ LS Sewer Pipe, PVC, ____ Inch Diameter SS-26 Lift Station (Entire System)SS-27 LS SANITARY SEWER SUBTOTAL:21,540.00 24,240.00 SALES TAX @ 10.1%2,175.54 2,448.24 SANITARY SEWER TOTAL:23,715.54 26,688.24 (B) (C) (D) (E) SITE IMPROVEMENT BOND QUANTITY WORKSHEET FOR SANITARY SEWER Quantity Remaining (Bond Reduction) (B)(C) Page 13 of 14 Ref 8-H Bond Quantity Worksheet SECTION II.e SANITARY SEWER Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430-7200 Date: Name:Project Name: PE Registration No:CED Plan # (LUA): Firm Name:CED Permit # (C): 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)45,327.34$ Future Public Improvements Subtotal (c)3,779.18$ Stormwater & Drainage Facilities (Public & Private) Subtotal (d)(d)97,238.12$ (e) (f) Site Restoration Civil Construction Permit Maintenance Bond 29,268.93$ Bond Reduction 2 Construction Permit Bond Amount 3 Minimum Bond Amount is $10,000.00 1 Estimate Only - May involve multiple and variable components, which will be established on an individual basis by Development Engineering. 2 The City of Renton allows one request only for bond reduction prior to the maintenance period. Reduction of not more than 70% of the original bond amount, provided that the remaining 30% will cover all remaining items to be constructed. 3 Required Bond Amounts are subject to review and modification by Development Engineering. * Note: The word BOND as used in this document means any financial guarantee acceptable to the City of Renton. ** Note: All prices include labor, equipment, materials, overhead, profit, and taxes. EST1 ((b) + (c) + (d)) x 20% -$ MAINTENANCE BOND */** (after final acceptance of construction) 5,345.36$ 45,327.34$ 165,229.13$ 5,345.36$ -$ 97,238.12$ -$ 170,574.49$ P (a) x 100% SITE IMPROVEMENT BOND QUANTITY WORKSHEET BOND CALCULATIONS 1/26/2022 Sheri Murata 41846 Core Design Inc. R ((b x 150%) + (d x 100%)) S (e) x 150% + (f) x 100% Bond Reduction: Existing Right-of-Way Improvements (Quantity Remaining)2 Bond Reduction: Stormwater & Drainage Facilities (Quantity Remaining)2 T (P +R - S) Prepared by:Project Information CONSTRUCTION BOND AMOUNT */** (prior to permit issuance) 425.885.7877 shm@coredesigninc.com Hardy Short Plat 21-000169 857 Field Avenue NE 1437650040 FOR APPROVAL ######## 12100 NE 195th St, Suite #300, Bothell, WA 98011 Page 14 of 14 Ref 8-H Bond Quantity Worksheet SECTION III. BOND WORKSHEET Unit Prices Updated: 01/07/2022 Version: 01/07/2022 Printed 1/26/2022 2016 KING COUNTY SURFACE WATER DESIGN MANUAL, REFERENCE D 4/24/2016 Page 1 STORMWATER FACILITY SUMMARY SHEET DPER Permit No.___________________ (provide one Stormwater Facility Summary Sheet per Natural Discharge Location)Date ___________________ OVERVIEW:NPDES Permit No.___________________ Project Name Parcel No.____________________________ Project Location Retired Parcel No.____________________________ Downstream Drainage Basins:Project includes Landscape Management Plan?yes Major Basin Name ______________________________________________(include copy with TIR as Appendix)no Immediate Basin Name ______________________________________________ GENERAL FACILITY INFORMATION: Leachable Metals Infiltration Impervious Surface Limit Type # of Type # of Type # of facilities Flow Control BMPs Ponds ______ Ponds ______ Ponds ______ Basic Clearing Limit Vaults ______ Tanks ______ Vaults ______ Conservation Drainage Facility Tanks ______ Trenches _____ Tanks ______ Flood Problem Landscape Management Plan If no flow control facility, check one: Project qualifies for KCSWDM Exemption (KCSWDM 1.2.3): Basic Exemption (Applies to Commercial parcels only)Area % of Total Redevelopment projects Cost Exemption for Parcel Redevelopment projects Direct Discharge Exemption Other _____________________ Total impervious surface served by Project qualifies for 0.1 cfs Exception per KCSWDM 1.2.3 flow control facility(ies) (sq ft) Impervious surface served by flow KCSWDM Adjustment No. ___________________control facility(ies) designed 1990 or later (sq ft) approved KCSWDM Adjustment No. __________________ Impervious surface served by Shared Facility Name/Location: _________________________ pervious surface absorption (sq ft) No flow control required (other, provide justification): Impervious surface served by approved ____________________________________________________ water quality facility(ies) (sq ft) Flow Control Performance Std Declarations of Covenant Recording No. Water QualityDetention TREATMENT SUMMARY FOR TOTAL IMPERVIOUS SURFACES ----- Total Impervious Acreage (ac) No flow control required per approved Flow control provided in regional/shared facility per approved PROVIDE FACILITY DETAILS AND FACILITY SKETCH FOR EACH FACILITY ON REVERSE. USE ADDITIONAL SHEETS AS NEEDED FOR ADDITIONAL FACILITIES Impervious Surface Exemption for Transportation Total Acreage (ac) 1437650040 857 Field Avenue NE Cedar River/Lake Washington Lower Cedar River TBD 1 Hardy Short Plat 4 4 1 2016 KING COUNTY SURFACE WATER DESIGN MANUAL, REFERENCE D 4/24/2016 Page 2 STORMWATER FACILITY SUMMARY SHEET DPER Permit No.___________________ (provide one Stormwater Facility Summary Sheet per Natural Discharge Location) Project Name Downstream Drainage Basins: Major Basin Name _______________________________ Project Location Immediate Basin Name ___________________________ FLOW CONTROL FACILITY:Basin: Facility Name/Number _______________________________________ New Facility Project Impervious Facility Location ____________________________________________ Existing Facility Acres Served ________ UIC? □ yes □ no UIC Site ID:% of Total Project Impervious cu.ft.Volume Factor Acres Served ________ _____________ ac.ft.____________of Safety _______No. of Lots Served ________ Control Structure location: _______________________________________________ Type of Control Structure:No. of Orifices/Restrictions __________ Riser in vault Size of Orifice/Restriction (in.) No.1 ______ cu.ft. Riser in Type II CB (numbered starting with lowest No.2 ______ ac.ft. Weir in Type II CB orifice): No.3 ______ (inches in decimal format)No.4 ______ WATER QUALITY FACILITIES Design Information Indicate no. of water quality facilities/BMPs for each type:Water Quality design flow (cfs) _______Flow dispersion Water Quality treated volume (sandfilter) (cu.ft.) _______Filter strip Water Quality storage volume (wetpool) (cu.ft.) _______Biofiltration swale regular, wet or Landscape management plan Farm management plan continuous inflow _______Wetvault combined w/detention ______High flow bypass structure (e.g., flow-splitter catch basin) _______Wetpond basic large combined w/detention ______Oil/water separator baffle coalescing plate _______Pre-settling pond ______Storm filter _______Stormwater wetland ______Pre-settling structure (Manufacturer:______________________) _______Sand filter basic large Sand bed depth ______Catch basin inserts (Manufacturer:________________________) regular linear vault (inches)______________Source controls _________________________________________ ● Is facility lined? yes no If so, what marker is used above liner?_____________________________________________________ Facility Summary Sheet Sketch: All detention, infiltration and water quality facilities must include a detailed sketch (11"x17" reduced size plan sheets preferred). Dam Safety Regulations (WA State Dept of Ecology): Reservoir Volume above natural grade Depth of Reservoir above natural grade (ft) Live Storage Volume Live Storage Depth (ft) Cedar River/Lake WashingtonHardy Short Plat Lower Cedar River 857 Field Avenue NE on Lot 1 0.41 63% 4,084 6.63 1.08 2 west end of vault N/A 4 4 4 4 4 .44 .44 .25 .31 N/A Core Design, Inc. HARDY SHORT PLAT Page 10-1 10. OPERATIONS AND MAINTENANCE The operations and maintenance information from Appendix A of the 2017 RSWDM are provided in this section. CITY OF RENTON SURFACE WATER DESIGN MANUAL 2017 City of Renton Surface Water Design Manual 12/12/2016 A-1 APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS This appendix contains the maintenance requirements for the following typical stormwater flow control and water quality facilities and on-site BMPs (ctrl/click the title to follow the link): No. 1 – Detention Ponds No. 2 – Infiltration Facilities No. 3 – Detention Tanks and Vaults No. 4 – Control Structure/Flow Restrictor No. 5 – Catch Basins and Manholes No. 6 – Conveyance Pipes and Ditches No. 7 – Debris Barriers (e.g., trash racks) No. 8 – Energy Dissipaters No. 9 – Fencing No. 10 – Gates/Bollards/Access Barriers No. 11 – Grounds (landscaping) No. 12 – Access Roads No. 13 – Basic Bioswale (grass) No. 14 – Wet Bioswale No. 15 – Filter Strip No. 16 – Wetpond No. 17 – Wetvault No. 18 – Stormwater Wetland No. 19 – Sand Filter Pond No. 20 – Sand Filter Vault No. 21 – Proprietary Facility Cartridge Filter Systems No. 22 – Baffle Oil/Water Separator No. 23 – Coalescing Plate Oil/Water Separator APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-2 No. 24 – Catch Basin Insert (not allowed in the city for oil control) No. 25 – Drywell BMP No. 26 – Gravel Filled Infiltration Trench BMP No. 27 – Gravel Filled Dispersion Trench BMP No. 28 – Native Vegetated Surface/Native Vegetated Landscape BMP No. 29 – Perforated Pipe Connections BMP No. 30 – Permeable Pavement BMP No. 31 – Bioretention BMP No. 32 – RainWater Harvesting BMP No. 33 – Rock Pad BMP No. 34 – Sheet Flow BMP No. 35 – Splash Block BMP No. 36 – Vegetated Roof BMP No. 37 – Rain Garden BMP No. 38 – Soil Amendment BMP No. 39 – Retained Trees No. 40 – Filterra System No. 41 – Compost Amended Vegetated Filter Strip (CAVFS) No. 42 – Media Filter Drain (MFD) No. 43 – Compost-Amended Biofiltration Swale APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-6 NO. 3 – DETENTION TANKS AND VAULTS MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Any trash and debris which exceed 1 cubic foot per 1,000 square feet (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In general, there should be no visual evidence of dumping. Trash and debris cleared from site. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to City personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where City personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Excessive growth of grass/groundcover Grass or groundcover exceeds 18 inches in height. Grass or groundcover mowed to a height no greater than 6 inches. Tank or Vault Storage Area Trash and debris Any trash and debris accumulated in vault or tank (includes floatables and non-floatables). No trash or debris in vault. Sediment accumulation Accumulated sediment depth exceeds 10% of the diameter of the storage area for ½ length of storage vault or any point depth exceeds 15% of diameter. Example: 72-inch storage tank would require cleaning when sediment reaches depth of 7 inches for more than ½ length of tank. All sediment removed from storage area. Tank Structure Plugged air vent Any blockage of the vent. Tank or vault freely vents. Tank bent out of shape Any part of tank/pipe is bent out of shape more than 10% of its design shape. Tank repaired or replaced to design. Gaps between sections, damaged joints or cracks or tears in wall A gap wider than ½-inch at the joint of any tank sections or any evidence of soil particles entering the tank at a joint or through a wall. No water or soil entering tank through joints or walls. Vault Structure Damage to wall, frame, bottom, and/or top slab Cracks wider than ½-inch, any evidence of soil entering the structure through cracks or qualified inspection personnel determines that the vault is not structurally sound. Vault is sealed and structurally sound. Inlet/Outlet Pipes Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. Damaged inlet/outlet pipes Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. Access Manhole Cover/lid not in place Cover/lid is missing or only partially in place. Any open manhole requires immediate maintenance. Manhole access covered. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-7 NO. 3 – DETENTION TANKS AND VAULTS MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Access Manhole (cont.) Locking mechanism not working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Cover/lid difficult to remove One maintenance person cannot remove cover/lid after applying 80 lbs of lift. Cover/lid can be removed and reinstalled by one maintenance person. Ladder rungs unsafe Missing rungs, misalignment, rust, or cracks. Ladder meets design standards. Allows maintenance person safe access. Large access doors/plate Damaged or difficult to open Large access doors or plates cannot be opened/removed using normal equipment. Replace or repair access door so it can opened as designed. Gaps, doesn't cover completely Large access doors not flat and/or access opening not completely covered. Doors close flat; covers access opening completely. Lifting rings missing, rusted Lifting rings not capable of lifting weight of door or plate. Lifting rings sufficient to lift or remove door or plate. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-8 NO. 4 – CONTROL STRUCTURE/FLOW RESTRICTOR MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Structure Trash and debris Trash or debris of more than ½ cubic foot which is located immediately in front of the structure opening or is blocking capacity of the structure by more than 10%. No Trash or debris blocking or potentially blocking entrance to structure. Trash or debris in the structure that exceeds 1/3 the depth from the bottom of basin to invert the lowest pipe into or out of the basin. No trash or debris in the structure. Deposits of garbage exceeding 1 cubic foot in volume. No condition present which would attract or support the breeding of insects or rodents. Sediment accumulation Sediment exceeds 60% of the depth from the bottom of the structure to the invert of the lowest pipe into or out of the structure or the bottom of the FROP-T section or is within 6 inches of the invert of the lowest pipe into or out of the structure or the bottom of the FROP-T section. Sump of structure contains no sediment. Damage to frame and/or top slab Corner of frame extends more than ¾ inch past curb face into the street (If applicable). Frame is even with curb. Top slab has holes larger than 2 square inches or cracks wider than ¼ inch. Top slab is free of holes and cracks. Frame not sitting flush on top slab, i.e., separation of more than ¾ inch of the frame from the top slab. Frame is sitting flush on top slab. Cracks in walls or bottom Cracks wider than ½ inch and longer than 3 feet, any evidence of soil particles entering structure through cracks, or maintenance person judges that structure is unsound. Structure is sealed and structurally sound. Cracks wider than ½ inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering structure through cracks. No cracks more than 1/4 inch wide at the joint of inlet/outlet pipe. Settlement/ misalignment Structure has settled more than 1 inch or has rotated more than 2 inches out of alignment. Basin replaced or repaired to design standards. Damaged pipe joints Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering the structure at the joint of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of inlet/outlet pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Ladder rungs missing or unsafe Ladder is unsafe due to missing rungs, misalignment, rust, cracks, or sharp edges. Ladder meets design standards and allows maintenance person safe access. FROP-T Section Damaged FROP-T T section is not securely attached to structure wall and outlet pipe structure should support at least 1,000 lbs of up or down pressure. T section securely attached to wall and outlet pipe. Structure is not in upright position (allow up to 10% from plumb). Structure in correct position. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-9 NO. 4 – CONTROL STRUCTURE/FLOW RESTRICTOR MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED FROP-T Section (cont.) Damaged FROP-T (cont.) Connections to outlet pipe are not watertight or show signs of deteriorated grout. Connections to outlet pipe are water tight; structure repaired or replaced and works as designed. Any holes—other than designed holes—in the structure. Structure has no holes other than designed holes. Cleanout Gate Damaged or missing cleanout gate Cleanout gate is missing. Replace cleanout gate. Cleanout gate is not watertight. Gate is watertight and works as designed. Gate cannot be moved up and down by one maintenance person. Gate moves up and down easily and is watertight. Chain/rod leading to gate is missing or damaged. Chain is in place and works as designed. Orifice Plate Damaged or missing orifice plate Control device is not working properly due to missing, out of place, or bent orifice plate. Plate is in place and works as designed. Obstructions to orifice plate Any trash, debris, sediment, or vegetation blocking the plate. Plate is free of all obstructions and works as designed. Overflow Pipe Obstructions to overflow pipe Any trash or debris blocking (or having the potential of blocking) the overflow pipe. Pipe is free of all obstructions and works as designed. Deformed or damaged lip of overflow pipe Lip of overflow pipe is bent or deformed. Overflow pipe does not allow overflow at an elevation lower than design Inlet/Outlet Pipe Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. Damaged inlet/outlet pipe Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. Metal Grates (If applicable) Unsafe grate opening Grate with opening wider than 7/8 inch. Grate opening meets design standards. Trash and debris Trash and debris that is blocking more than 20% of grate surface. Grate free of trash and debris. footnote to guidelines for disposal Damaged or missing grate Grate missing or broken member(s) of the grate. Grate is in place and meets design standards. Manhole Cover/Lid Cover/lid not in place Cover/lid is missing or only partially in place. Any open structure requires urgent maintenance. Cover/lid protects opening to structure. Locking mechanism not working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Cover/lid difficult to remove One maintenance person cannot remove cover/lid after applying 80 lbs. of lift. Cover/lid can be removed and reinstalled by one maintenance person. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-10 NO. 5 – CATCH BASINS AND MANHOLES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Structure Sediment accumulation Sediment exceeds 60% of the depth from the bottom of the catch basin to the invert of the lowest pipe into or out of the catch basin or is within 6 inches of the invert of the lowest pipe into or out of the catch basin. Sump of catch basin contains no sediment. Trash and debris Trash or debris of more than ½ cubic foot which is located immediately in front of the catch basin opening or is blocking capacity of the catch basin by more than 10%. No Trash or debris blocking or potentially blocking entrance to catch basin. Trash or debris in the catch basin that exceeds 1/3 the depth from the bottom of basin to invert the lowest pipe into or out of the basin. No trash or debris in the catch basin. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases (e.g., methane). No dead animals or vegetation present within catch basin. Deposits of garbage exceeding 1 cubic foot in volume. No condition present which would attract or support the breeding of insects or rodents. Damage to frame and/or top slab Corner of frame extends more than ¾ inch past curb face into the street (If applicable). Frame is even with curb. Top slab has holes larger than 2 square inches or cracks wider than ¼ inch. Top slab is free of holes and cracks. Frame not sitting flush on top slab, i.e., separation of more than ¾ inch of the frame from the top slab. Frame is sitting flush on top slab. Cracks in walls or bottom Cracks wider than ½ inch and longer than 3 feet, any evidence of soil particles entering catch basin through cracks, or maintenance person judges that catch basin is unsound. Catch basin is sealed and is structurally sound. Cracks wider than ½ inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. No cracks more than 1/4 inch wide at the joint of inlet/outlet pipe. Settlement/ misalignment Catch basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Basin replaced or repaired to design standards. Damaged pipe joints Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering the catch basin at the joint of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of inlet/outlet pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Inlet/Outlet Pipe Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-11 NO. 5 – CATCH BASINS AND MANHOLES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Inlet/Outlet Pipe (cont.) Damaged inlet/outlet pipe Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. Metal Grates (Catch Basins) Unsafe grate opening Grate with opening wider than 7/8 inch. Grate opening meets design standards. Trash and debris Trash and debris that is blocking more than 20% of grate surface. Grate free of trash and debris. footnote to guidelines for disposal Damaged or missing grate Grate missing or broken member(s) of the grate. Any open structure requires urgent maintenance. Grate is in place and meets design standards. Manhole Cover/Lid Cover/lid not in place Cover/lid is missing or only partially in place. Any open structure requires urgent maintenance. Cover/lid protects opening to structure. Locking mechanism not working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Cover/lid difficult to remove One maintenance person cannot remove cover/lid after applying 80 lbs. of lift. Cover/lid can be removed and reinstalled by one maintenance person. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-12 NO. 6 – CONVEYANCE PIPES AND DITCHES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Pipes Sediment & debris accumulation Accumulated sediment or debris that exceeds 20% of the diameter of the pipe. Water flows freely through pipes. Vegetation/root growth in pipe Vegetation/roots that reduce free movement of water through pipes. Water flows freely through pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Damage to protective coating or corrosion Protective coating is damaged; rust or corrosion is weakening the structural integrity of any part of pipe. Pipe repaired or replaced. Damaged pipes Any dent that decreases the cross section area of pipe by more than 20% or is determined to have weakened structural integrity of the pipe. Pipe repaired or replaced. Ditches Trash and debris Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Trash and debris cleared from ditches. Sediment accumulation Accumulated sediment that exceeds 20% of the design depth. Ditch cleaned/flushed of all sediment and debris so that it matches design. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to City personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where City personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Excessive vegetation growth Vegetation that reduces free movement of water through ditches. Water flows freely through ditches. Erosion damage to slopes Any erosion observed on a ditch slope. Slopes are not eroding. Rock lining out of place or missing (If applicable) One layer or less of rock exists above native soil area 5 square feet or more, any exposed native soil. Replace rocks to design standards. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-40 NO. 28 – NATIVE VEGETATED SURFACE/NATIVE VEGETATED LANDSCAPE BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Site Trash and debris Trash and debris accumulated on the native vegetated surface/native vegetated landscape site. Native vegetated surface site free of any trash or debris. Vegetation Insufficient vegetation Less than two species each of native trees, shrubs, and groundcover occur in the design area. A minimum of two species each of native trees, shrubs, and groundcover is established and healthy. Poor vegetation coverage Less than 90% if the required vegetated area has healthy growth. A minimum of 90% of the required vegetated area has healthy growth. Undesirable vegetation present Weeds, blackberry, and other undesirable plants are invading more than 10% of vegetated area. Less than 10% undesirable vegetation occurs in the required native vegetated surface area. Vegetated Area Soil compaction Soil in the native vegetation area compacted. Less than 8% of native vegetation area is compacted. Insufficient vegetation Less than 3.5 square feet of native vegetation area for every 1 square foot of impervious surface. A minimum of 3.5 square feet of native vegetation area for every 1 square foot of impervious surface. Excess slope Slope of native vegetation area greater than 15%. Slope of native growth area does not exceed 15%. NO. 29 – PERFORATED PIPE CONNECTIONS BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Preventive Blocking, obstructions Debris or trash limiting flow into perforated pipe system or outfall of BMP is plugged or otherwise nonfunctioning. Outfall of BMP is receiving designed flows from perforated pipe connection. Inflow Inflow impeded Inflow into the perforated pipe is partially or fully blocked or altered to prevent flow from getting into the pipe. Inflow to the perforated pipe is unimpeded. Pipe Trench Area Surface compacted Ground surface over the perforated pipe trench is compacted or covered with impermeable material. Ground surface over the perforated pipe is not compacted and free of any impervious cover. Outflow Outflow impeded Outflow from the perforated pipe into the public drainage system is blocked. Outflow to the public drainage system is unimpeded. Outfall Area Erosion or landslides Existence of the perforated pipe is causing or exasperating erosion or landslides. Perforated pipe system is sealed off and an alternative BMP is implemented. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-41 NO. 30 – PERMEABLE PAVEMENT BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Preventive Surface cleaning/ vegetation control Media surface vacuumed or pressure washed annually, vegetation controlled to design maximum. Weed growth suggesting sediment accumulation. No dirt, sediment, or debris clogging porous media, or vegetation limiting infiltration. Porous Concrete, Porous Asphaltic Concrete, and Permeable Pavers Trash and debris Trash and debris on the pavement interfering with infiltration; leaf drop in fall season. No trash or debris interfering with infiltration. Sediment accumulation Sediment accumulation on the pavement interfering with infiltration; runoff from adjacent areas depositing sediment/debris on pavement. Pavement infiltrates as designed; adjacent areas stabilized. Insufficient infiltration rate Pavement does not infiltrate at a rate of 10 inches per hour. Pavement infiltrates at a rate greater than 10 inches per hour. Excessive ponding Standing water for a long period of time on the surface of the pavement. Standing water infiltrates at the desired rate. Broken or cracked pavement Pavement is broken or cracked. No broken pavement or cracks on the surface of the pavement. Settlement Uneven pavement surface indicating settlement of the subsurface layer. Pavement surface is uniformly level. Moss growth Moss growing on pavement interfering with infiltration. No moss interferes with infiltration. Inflow restricted Inflow to the pavement is diverted, restricted, or depositing sediment and debris on the pavement. Inflow to pavement is unobstructed and not bringing sediment or debris to the pavement. Underdrain not freely flowing Underdrain is not flowing when pavement has been infiltrating water. Underdrain flows freely when water is present. Overflow not controlling excess water Overflow not controlling excess water to desired location; native soil is exposed or other signs of erosion damage are present. Overflow permits excess water to leave the site at the desired location; Overflow is stabilized and appropriately armored. Permeable Pavers Broken or missing pavers Broken or missing paving blocks on surface of pavement. No missing or broken paving blocks interfering with infiltration. Uneven surface Uneven surface due to settlement or scour of fill in the interstices of the paving blocks. Pavement surface is uniformly level. Compaction Poor infiltration due to soil compaction between paving blocks. No soil compaction in the interstices of the paver blocks limiting infiltration. Poor vegetation growth (if applicable) Grass in the interstices of the paving blocks is dead. Healthy grass is growing in the interstices of the paver blocks. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 2017 City of Renton Surface Water Design Manual 12/12/2016 A-47 NO. 38 – SOIL AMENDMENT BMP MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Soil Media Unhealthy vegetation Vegetation not fully covering ground surface or vegetation health is poor. Yellowing: possible Nitrogen (N) deficiency. Poor growth: possible Phosphorous (P) deficiency. Poor flowering, spotting or curled leaves, or weak roots or stems: possible Potassium (K) deficiency. Plants are healthy and appropriate for site conditions Inadequate soil nutrients and structure In the fall, return leaf fall and shredded woody materials from the landscape to the site when possible Soil providing plant nutrients and structure Excessive vegetation growth Grass becomes excessively tall (greater than 10 inches); nuisance weeds and other vegetation start to take over. Healthy turf- “grasscycle” (mulch-mow or leave the clippings) to build turf health Weeds Preventive maintenance Avoid use of pesticides (bug and weed killers), like “weed & feed,” which damage the soil Fertilizer needed Where fertilization is needed (mainly turf and annual flower beds), a moderate fertilization program should be used which relies on compost, natural fertilizers or slow-release synthetic balanced fertilizers Integrated Pest Management (IPM) protocols for fertilization followed Bare spots Bare spots on soil No bare spots, area covered with vegetation or mulch mixed into the underlying soil. Compaction Poor infiltration due to soil compaction • To remediate compaction, aerate soil, till to at least 8-inch depth, or further amend soil with compost and re-till • If areas are turf, aerate compacted areas and top dress them with 1/4 to 1/2 inch of compost to renovate them • If drainage is still slow, consider investigating alternative causes (e.g., high wet season groundwater levels, low permeability soils) • Also consider site use and protection from compacting activities No soil compaction Poor infiltration Soils become waterlogged, do not appear to be infiltrating. Facility infiltrating properly Erosion/Scouring Erosion Areas of potential erosion are visible Causes of erosion (e.g., concentrate flow entering area, channelization of runoff) identified and damaged area stabilized (regrade, rock, vegetation, erosion control matting).For deep channels or cuts (over 3 inches in ponding depth), temporary erosion control measures in place until permanent repairs can be made Grass/Vegetation Unhealthy vegetation Less than 75% of planted vegetation is healthy with a generally good appearance. Healthy vegetation. Unhealthy plants removed/replaced. Appropriate vegetation planted in terms of exposure, soil and soil moisture. Noxious Weeds Noxious weeds Listed noxious vegetation is present (refer to current County noxious weed list). No noxious weeds present. APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-48 NO. 39 – RETAINED TREES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Tree Dead or declining Dead, damaged, or declining Tree replaced per planting plan or acceptable substitute NO. 40 – FILTERRA SYSTEM MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITION WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED In addition to the specific maintenance criteria provided below, all manufacturer’s requirements shall be followed. Facility – General Requirements Life cycle Once per year, except mulch and trash removal twice per year Facility is re-inspected and any needed maintenance performed Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries, or paint Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Inlet Excessive sediment or trash accumulation Accumulated sediments or trash impair free flow of water into system Inlet should be free of obstructions allowing free distributed flow of water into system Mulch Cover Trash and floatable debris accumulation Excessive trash and/or debris accumulation Minimal trash or other debris on mulch cover. Mulch cover raked level. “Ponding” of water on mulch cover “Ponding” in unit could be indicative of clogging due to excessive fine sediment accumulation or spill of petroleum oils Stormwater should drain freely and evenly through mulch cover Proprietary Filter Media/ Vegetation Substrate “Ponding” of water on mulch cover after mulch cover has been maintained Excessive fine sediment passes the mulch cover and clogs the filter media/vegetative substrate Stormwater should drain freely and evenly through mulch cover. Replace substrate and vegetation when needed Vegetation Plants not growing or in poor condition Soil/mulch too wet, evidence of spill, incorrect plant selection, pest infestation, and/or vandalism to plants Plants should be healthy and pest free Media/mulch too dry Irrigation is required Plants absent Plants absent Appropriate plants are present Excessive plant growth Excessive plant growth inhibits facility function or becomes a hazard for pedestrian and vehicular circulation and safety Pruning and/or thinning vegetation maintains proper plant density. Appropriate plants are present. Structure Structure has visible cracks Cracks wider than ½ inch Evidence of soil particles entering the structure through the cracks Structure is sealed and structurally sound ————————————————————————————————— MGS FLOOD PROJECT REPORT Program Version: MGSFlood 4.56 Program License Number: 200210008 Project Simulation Performed on: 01/13/2022 2:52 PM Report Generation Date: 01/13/2022 2:52 PM ————————————————————————————————— Input File Name: Vault Sizing 65%.fld Project Name: Hardy Short Plat Analysis Title: Vault Sizing Comments: ———————————————— PRECIPITATION INPUT ———————————————— Computational Time Step (Minutes): 15 Extended Precipitation Time Series Selected Climatic Region Number: 16 Full Period of Record Available used for Routing Precipitation Station : 96004405 Puget East 44 in_5min 10/01/1939-10/01/2097 Evaporation Station : 961044 Puget East 44 in MAP Evaporation Scale Factor : 0.750 HSPF Parameter Region Number: 3 HSPF Parameter Region Name : USGS Default ********** Default HSPF Parameters Used (Not Modified by User) *************** ********************** WATERSHED DEFINITION *********************** Predevelopment/Post Development Tributary Area Summary Predeveloped Post Developed Total Subbasin Area (acres) 0.406 0.406 Area of Links that Include Precip/Evap (acres) 0.000 0.000 Total (acres) 0.406 0.406 ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Subbasin 1 ---------- -------Area (Acres) -------- Till Forest 0.366 Impervious 0.040 ---------------------------------------------- Subbasin Total 0.406 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Subbasin 1 ---------- -------Area (Acres) -------- Till Grass 0.152 Impervious 0.254 ---------------------------------------------- Subbasin Total 0.406 ************************* LINK DATA ******************************* ----------------------SCENARIO: PREDEVELOPED Number of Links: 0 ************************* LINK DATA ******************************* ----------------------SCENARIO: POSTDEVELOPED Number of Links: 1 ------------------------------------------ Link Name: Vault Link Type: Structure Downstream Link: None Prismatic Pond Option Used Pond Floor Elevation (ft) : 456.59 Riser Crest Elevation (ft) : 463.22 Max Pond Elevation (ft) : 463.72 Storage Depth (ft) : 6.63 Pond Bottom Length (ft) : 43.0 Pond Bottom Width (ft) : 14.0 Pond Side Slopes (ft/ft) : Z1= 0.00 Z2= 0.00 Z3= 0.00 Z4= 0.00 Bottom Area (sq-ft) : 602. Area at Riser Crest El (sq-ft) : 602. (acres) : 0.014 Volume at Riser Crest (cu-ft) : 3,991. (ac-ft) : 0.092 Area at Max Elevation (sq-ft) : 602. (acres) : 0.014 Vol at Max Elevation (cu-ft) : 4,292. (ac-ft) : 0.099 Hydraulic Conductivity (in/hr) : 0.00 Massmann Regression Used to Estimate Hydralic Gradient Depth to Water Table (ft) : 100.00 Bio-Fouling Potential : Low Maintenance : Average or Better Riser Geometry Riser Structure Type : Circular Riser Diameter (in) : 12.00 Common Length (ft) : 0.000 Riser Crest Elevation : 463.22 ft Hydraulic Structure Geometry Number of Devices: 4 ---Device Number 1 --- Device Type : Circular Orifice Control Elevation (ft) : 456.59 Diameter (in) : 0.44 Orientation : Horizontal Elbow : No ---Device Number 2 --- Device Type : Circular Orifice Control Elevation (ft) : 460.30 Diameter (in) : 0.44 Orientation : Horizontal Elbow : Yes ---Device Number 3 --- Device Type : Circular Orifice Control Elevation (ft) : 461.65 Diameter (in) : 0.25 Orientation : Horizontal Elbow : Yes ---Device Number 4 --- Device Type : Circular Orifice Control Elevation (ft) : 462.05 Diameter (in) : 0.31 Orientation : Horizontal Elbow : Yes **********************FLOOD FREQUENCY AND DURATION STATISTICS******************* ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 Number of Links: 0 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 Number of Links: 1 ********** Subbasin: Subbasin 1 ********** Flood Frequency Data(cfs) (Recurrence Interval Computed Using Gringorten Plotting Position) Tr (yrs) Flood Peak (cfs) ====================================== 2-Year 0.115 5-Year 0.153 10-Year 0.183 25-Year 0.233 50-Year 0.294 100-Year 0.364 200-Year 0.372 500-Year 0.382 ********** Link: Vault ********** Link WSEL Stats WSEL Frequency Data(ft) (Recurrence Interval Computed Using Gringorten Plotting Position) Tr (yrs) WSEL Peak (ft) ====================================== 1.05-Year 458.413 1.11-Year 458.742 1.25-Year 459.063 2.00-Year 459.939 3.33-Year 460.455 5-Year 460.959 10-Year 461.925 25-Year 462.863 50-Year 463.233 100-Year 463.238 ***********Groundwater Recharge Summary ************* Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures Total Predeveloped Recharge During Simulation Model Element Recharge Amount (ac-ft) ----------------------------------------------------------------------------------------------- Subbasin: Subbasin 1 69.628 _____________________________________ Total: 69.628 Total Post Developed Recharge During Simulation Model Element Recharge Amount (ac-ft) ----------------------------------------------------------------------------------------------- Subbasin: Subbasin 1 19.577 Link: Vault 0.000 _____________________________________ Total: 19.577 Total Predevelopment Recharge is Greater than Post Developed Average Recharge Per Year, (Number of Years= 158) Predeveloped: 0.441 ac-ft/year, Post Developed: 0.124 ac-ft/year ***********Water Quality Facility Data ************* ----------------------SCENARIO: PREDEVELOPED Number of Links: 0 ----------------------SCENARIO: POSTDEVELOPED Number of Links: 1 ********** Link: Vault ********** Basic Wet Pond Volume (91% Exceedance): 1406. cu-ft Computed Large Wet Pond Volume, 1.5*Basic Volume: 2109. cu-ft 2-Year Discharge Rate : 0.009 cfs 15-Minute Timestep, Water Quality Treatment Design Discharge On-line Design Discharge Rate (91% Exceedance): 0.04 cfs Off-line Design Discharge Rate (91% Exceedance): 0.02 cfs Infiltration/Filtration Statistics-------------------- Inflow Volume (ac-ft): 164.83 Inflow Volume Including PPT-Evap (ac-ft): 164.83 Total Runoff Infiltrated (ac-ft): 0.00, 0.00% Total Runoff Filtered (ac-ft): 0.00, 0.00% Primary Outflow To Downstream System (ac-ft): 164.82 Secondary Outflow To Downstream System (ac-ft): 0.00 Volume Lost to ET (ac-ft): 0.00 Percent Treated (Infiltrated+Filtered+ET)/Total Volume: 0.00% ***********Compliance Point Results ************* Scenario Predeveloped Compliance Subbasin: Subbasin 1 Scenario Postdeveloped Compliance Link: Vault *** Point of Compliance Flow Frequency Data *** Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Postdevelopment Runoff Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs) ---------------------------------------------------------------------------------------------------------------------- 2-Year 2.086E-02 2-Year 9.454E-03 5-Year 2.991E-02 5-Year 1.478E-02 10-Year 3.755E-02 10-Year 1.902E-02 25-Year 5.051E-02 25-Year 2.477E-02 50-Year 5.877E-02 50-Year 4.799E-02 100-Year 6.410E-02 100-Year 5.652E-02 200-Year 8.825E-02 200-Year 7.147E-02 500-Year 0.121 500-Year 9.140E-02 ** Record too Short to Compute Peak Discharge for These Recurrence Intervals **** Flow Duration Performance **** Excursion at Predeveloped 50%Q2 (Must be Less Than or Equal to 0%): -32.0% PASS Maximum Excursion from 50%Q2 to Q2 (Must be Less Than or Equal to 0%): -1.1% PASS Maximum Excursion from Q2 to Q50 (Must be less than 10%): -3.8% PASS Percent Excursion from Q2 to Q50 (Must be less than 50%): 0.0% PASS ------------------------------------------------------------------------------------------------- MEETS ALL FLOW DURATION DESIGN CRITERIA: PASS ------------------------------------------------------------------------------------------------- **** LID Duration Performance **** Excursion at Predeveloped 8%Q2 (Must be Less Than 0%): 205.0% FAIL Maximum Excursion from 8%Q2 to 50%Q2 (Must be Less Than 0%): 337.8% FAIL ------------------------------------------------------------------------------------------------- LID DURATION DESIGN CRITERIA: FAIL ------------------------------------------------------------------------------------------------- Lake Desire Shady Lake (Mud Lake) Panther Lake Lake Youngs Lake Washington B l ack Ri v e r Gr ee n Ri ver Ce darRi v erUV900 UV167 UV515 UV169 UV900 UV169 UV167BN IncBN IncBBNNIInnccSSEE RReennttoonn IIssssaaqquuaahh RR dd RReennttoonnMMaapplleeVVaalllleeyyRRdd MMaapplleeVVaalllleeyyHHwwyy 110088tthhAAvveeSSEESSWW SSuunnsseettBBllvvdd RRaaii nnii eerrAAvveeNNNE 3rd S t NE 3rd S t SW 43rd StSW 43rd St SSEE CC aarrrrRR dd NE 4th StNE 4th St SSEERReennttoonn MMaappllee VVaalllleeyy RRddLLooggaannAAvveeNN SR 515SR 515PPaarrkkAAvveeNNOOaakkeessddaalleeAAvveeSSWWSSuunnsseettBBllvvddNNEE DDuuvvaallllAAvveeNNEEI-405 FWYI-405 FWY II--440055FFWWYYSR 167SR 1671144 00tthh WWaayy SS EENNEE2277tthh SStt 115566tthhAAvveeSSEEUUnniioonnAAvveeNNEE111166tthhAAvveeSSEESW 7th StSW 7th St N 8th StN 8th St PP uuggeettDD rrSSEE RR ee nnttoo nnAAvvee SS SSWW 2277tthh SStt BBeennssoonnRRddSSWWiilllliiaammssAAvveeSSMMoonnrrooeeAAvveeNNEESE 128th StSE 128th St II nntt eerr uurr bbaannAA vvee SS HHooqquuiiaammAAvveeNNEE8844tthhAAvveeSSSSEEPPeett rr oovvii tt sskkyyRRddEEVVaalllleeyyHHwwyySE 192nd StSE 192nd St SE 60th StSE 60th St TTaallbboottRRddSSRRee nn tt oo nn AAvveeSS116644tthhAAvveeSSEESE 208th StSE 208th St SE 72nd StSE 72nd St RR aaiinniieerr AAvvee SS 111166tthhAAvveeSSEES 128th StS 128th St NNeewwccaassttllee WWaayy SS 221122tthh SStt SS118800tthh SStt CCooaall CCrreeeekkPPkkwwyySSEESW 41st StSW 41st St 114400tthhAAvveeSSEE112288tthhAAvveeSSEE6688tthhAAvveeSSSSEE 116688tthh SStt NE 12th StNE 12th St BBeeaacc oonn AAvv ee SSFFoorreesstt DDrr SSEE SSEE 116644tthh SStt 114488tthhAAvveeSSEESSEE MMaayy VVaalllleeyyRRdd SS EE JJoonneess RRdd SS EE 22 00 44 tthh WW aayySW 34th StSW 34th St SE 144th StSE 144th St 114488tthhAAvveeSSEE115544tthhPPllSSEELL aa kk ee WWaa sshhii nnggtt oonnBBll vvddNNEEddmmoonnddssAAvveeNNEEAAbbeerrddeeeennAAvveeNNEEEEMM eerrcceerrWWaayyWWeessttVVaalllleeyyHHwwyyEast Valley RdEast Valley Rd,§-405 ,§-405 ,§-405 µ0 1 2 Miles Flow Control Application Map Reference 1-A Date: 01/09/2014 Flow Control Standards Peak Rate Flow Control Standard (Existing Site Conditions) Flow Control Duration Standard (Existing Site Conditions) Flow Control Duration Standard (Forested Conditions) Flood Problem Flow Unincorporated King County Flow Control Standards Renton City Limits Potential Annexation Area PROJECT SITE k k k k k k k k k k k k k k k k k k k k k k k k k k k kk k k k k k k k k k k k k k k k k k k k HoquiamAveNEE Valley Hwy84thAveSNEParkDr SW 7th St SE 128th St SE 192nd StLind Ave SWMainAveSS 132nd St Factory PlN Tal bot Rd SN 3rd St RainierAveS 164thAveSETukwilaPkwy SPugetDr NE 4th St S 3rd St S 1 2 9 th S t68thAveSSWSunsetBlvd SW 16th St 116thAveSEN 4th St In t e r u r b a n A v e S WilliamsAveNBronsonWa y N NE7thSt 124thAveSES 7th St SERento n IssaquahRd Rai ni er AveNNewcastle Way CoalCre ek PkwySESW 41st St Ta y l o r P l NW NESunsetBlvdWellsAveNUnionAveNENE 3rd St Hardie Av eSWS180th St Maple V a l l e y H w y 140thAveSES G ra d y W ayS 2 1 s tSt BensonRdSRento n AveS87thAveS128thAveSE148thAveSESW 43rd St SEC arrRd SE 168thSt Beacon Ave S 68thAveSLoganAveN108thAveSEForestDrSE S2ndSt 141s t AveSERainierAveS 156thAveSES E 183rdStBe n s on D r S S124th StS 43rd St Airport Way S W G ra dyW a y SE J o n es RdSunsetBlvdN Puget Dr SESE 204th Way SW 34th StMo n sterRdSW SE 142nd Pl WestValleyHwySSEMayValleyRd SunsetBlvdNS Carr RdHouserWayNNewcastleGolfClubRd S 133rd St WilliamsAveSWellsAveSEMercerWay154thPlSEDuvallAveNELoganAveSMonroeAveNESunsetBlvdNEEdmondsAveNEStevens AveNWRaini er AveSTalbotRdSOakesdaleAveSWTaylorAveNW164thAveSERainierAveSWestVall eyHwyWestValleyHwyParkAveN108thAveSE6 6th A v e S WM ercerWayWMercer W ay LakemontBl vdSE132ndAve SELakeWashingtonBlvdNE140thWaySE East Valley Rd68thAveS³City of Renton Sensitive Areas 0 0.5 10.25 Miles Information Technology - GIS mapsupport@rentonwa.govPrinted on: 11/12/2014 Data Sources: City of Renton, King County This document is a graphic representation, not guaranteed to survey accuracy, and is based on the best informationavailable as of the date shown. This map is intended for City display purposes only. Renton City Limits k Education Fire Station K Valley Medical Center Aquifer Protection Zone 1 Zone 1 Modified Zone 2 Coordinate System: NAD 1983 HARN StatePlane Washington North FIPS 4601 FeetProjection: Lambert Conformal ConicDatum: North American 1983 HARN PROJECT SITE RentonKent Newcastle King CountyTukwilaMercer Island Bellevu e Lake Washington Lake Youngs Panther Lake Lake Boren Cedar RiverBlack River May Creek Springbrook Creek Cougar MountainCougar Mountain Coal Creek ParkCoal Creek Park Cedar River Natural ZoneCedar River Natural Zone May Creek ParkMay Creek Park Soos Creek Park and TrailSoos Creek Park and Trail Black River Riparian ForestBlack River Riparian Forest McGarvey Open SpaceMcGarvey Open Space Maplewood Community ParkMaplewood Community Park ValleyValley BensonBenson HighlandsHighlands West HillWest Hill East PlateauEast Plateau SE 192ND STTALBOT RD S140TH AVE SERAI N I E R A V E S EAST VALLEY RDSE 168TH ST RENTON A V E S116TH AVE SENE 12TH STE M ERCER WAY148TH AVE SENE 7TH S T84TH AVE SHOQUIAM AVE NENEWCASTLE WAY W M E RCER WAY S 128TH ST SW 41ST ST PARK AVE N128TH AVE SESE JONES R D E VALLEY HWYSE 72ND ST SE 164TH ST NILE AVE NEN 10TH S T SE 183RD S TUNION AVE NE156TH AVE SEUNION AVE SENE 2ND ST 148TH AVE SESE 164TH STLIND AVE SWUNION AVE NE116TH AVE SESW 7TH ST N 8TH ST EDMONDS AVE NEPUGET DR S E NE 27TH ST 156TH AVE SERENTON AVE S BENSON RD SMONROE AVE NE116TH AVE SENE 4TH ST SR 515 SUNS E T B LV D N E PARK AVE NMAPLE VALLEY HWY SW 43RD ST NE 3RD STLOGAN AVE NSW SU NSET BLVD SW GRADY W A Y N 3RD STRAINIER AVE N 140TH WAY SESR 167108TH AVE SEN 6TH ST S 2ND ST 108TH AVE SESR 515[^405 [^405 Effective FEMA Flood Insurance Rate Map µ Legend Renton City Limits Zone AE, A, AH, AO - Regulatory Zone X - Non Regulatory 0 0.5 10.25 Miles Public Works - Surface Water UtilityPrint Date: 11/05/2012 Data Sources: City of Renton, FEMA FIRM revised May 16, 1995.Cedar River flood hazard area updated with FEMA Cedar RiverLOMR (Case No. 06-10-B569P) approved December 4, 2006. This document is a graphic representation, not guaranteedto survey accuracy, and is based on the best informationavailable as of the date shown. This map is intended forCity display purposes only. PROJECT SITE k k k k k k k k k k k k k k k k k k k k k k k k k k k kk k k k k k k k k k k k k k k k k k k k HoquiamAveNEE Valley Hwy84thAveSNEParkDr SW 7th St SE 128th St SE 192nd StLind Ave SWMainAveSS 132nd St Factory PlN Tal bot Rd SN 3rd St RainierAveS 164thAveSETukwilaPkwy SPugetDr NE 4th St S 3rd St S 1 2 9 th S t68thAveSSWSunsetBlvd SW 16th St 116thAveSEN 4th St In t e r u r b a n A v e S WilliamsAveNBronsonWa y N NE7thSt 124thAveSES 7th St SERento n IssaquahRd Rai ni er AveNNewcastle Way CoalCre ek PkwySESW 41st St Ta y l o r P l NW NESunsetBlvdWellsAveNUnionAveNENE 3rd St Hardie Av eSWS180th St Maple V a l l e y H w y 140thAveSES G ra d y W ayS 2 1 s tSt BensonRdSRento n AveS87thAveS128thAveSE148thAveSESW 43rd St SEC arrRd SE 168thSt Beacon Ave S 68thAveSLoganAveN108thAveSEForestDrSE S2ndSt 141s t AveSERainierAveS 156thAveSES E 183rdStBe n s on D r S S124th StS 43rd St Airport Way S W G ra dyW a y SE J o n es RdSunsetBlvdN Puget Dr SESE 204th Way SW 34th StMo n sterRdSW SE 142nd Pl WestValleyHwySSEMayValleyRd SunsetBlvdNS Carr RdHouserWayNNewcastleGolfClubRd S 133rd St WilliamsAveSWellsAveSEMercerWay154thPlSEDuvallAveNELoganAveSMonroeAveNESunsetBlvdNEEdmondsAveNEStevens AveNWRaini er AveSTalbotRdSOakesdaleAveSWTaylorAveNW164thAveSERainierAveSWestVall eyHwyWestValleyHwyParkAveN108thAveSE6 6th A v e S WM ercerWayWMercer W ay LakemontBl vdSE132ndAve SELakeWashingtonBlvdNE140thWaySE East Valley Rd68thAveS³City of Renton Sensitive Areas 0 0.5 10.25 Miles Information Technology - GIS mapsupport@rentonwa.govPrinted on: 11/12/2014 Data Sources: City of Renton, King County This document is a graphic representation, not guaranteed to survey accuracy, and is based on the best informationavailable as of the date shown. This map is intended for City display purposes only. Renton City Limits k Education Fire Station K Valley Medical Center Coal Mine HazardsSeverity HIGH MODERATE UNCLASSIFIED Coordinate System: NAD 1983 HARN StatePlane Washington North FIPS 4601 FeetProjection: Lambert Conformal ConicDatum: North American 1983 HARN PROJECT SITE k k k k k k k k k k k k k k k k k k k k k k k k k k k kk k k k k k k k k k k k k k k k k k k k HoquiamAveNEE Valley Hwy84thAveSNEParkDr SW 7th St SE 128th St SE 192nd StLind Ave SWMainAveSS 132nd St Factory PlN Tal bot Rd SN 3rd St RainierAveS 164thAveSETukwilaPkwy SPugetDr NE 4th St S 3rd St S 1 2 9 th S t68thAveSSWSunsetBlvd SW 16th St 116thAveSEN 4th St In t e r u r b a n A v e S WilliamsAveNBronsonWa y N NE7thSt 124thAveSES 7th St SERento n IssaquahRd Rai ni er AveNNewcastle Way CoalCre ek PkwySESW 41st St Ta y l o r P l NW NESunsetBlvdWellsAveNUnionAveNENE 3rd St Hardie Av eSWS180th St Maple V a l l e y H w y 140thAveSES G ra d y W ayS 2 1 s tSt BensonRdSRento n AveS87thAveS128thAveSE148thAveSESW 43rd St SEC arrRd SE 168thSt Beacon Ave S 68thAveSLoganAveN108thAveSEForestDrSE S2ndSt 141s t AveSERainierAveS 156thAveSES E 183rdStBe n s on D r S S124th StS 43rd St Airport Way S W G ra dyW a y SE J o n es RdSunsetBlvdN Puget Dr SESE 204th Way SW 34th StMo n sterRdSW SE 142nd Pl WestValleyHwySSEMayValleyRd SunsetBlvdNS Carr RdHouserWayNNewcastleGolfClubRd S 133rd St WilliamsAveSWellsAveSEMercerWay154thPlSEDuvallAveNELoganAveSMonroeAveNESunsetBlvdNEEdmondsAveNEStevens AveNWRaini er AveSTalbotRdSOakesdaleAveSWTaylorAveNW164thAveSERainierAveSWestVall eyHwyWestValleyHwyParkAveN108thAveSE6 6th A v e S WM ercerWayWMercer W ay LakemontBl vdSE132ndAve SELakeWashingtonBlvdNE140thWaySE East Valley Rd68thAveS³City of Renton Sensitive Areas 0 0.5 10.25 Miles Information Technology - GIS mapsupport@rentonwa.govPrinted on: 11/12/2014 Data Sources: City of Renton, King County This document is a graphic representation, not guaranteed to survey accuracy, and is based on the best informationavailable as of the date shown. This map is intended for City display purposes only. Renton City Limits k Education Fire Station K Valley Medical Center Erosion HazardSeverity High Coordinate System: NAD 1983 HARN StatePlane Washington North FIPS 4601 FeetProjection: Lambert Conformal ConicDatum: North American 1983 HARN PROJECT SITE k k k k k k k k k k k k k k k k k k k k k k k k k k k kk k k k k k k k k k k k k k k k k k k k HoquiamAveNEE Valley Hwy84thAveSNEParkDr SW 7th St SE 128th St SE 192nd StLind Ave SWMainAveSS 132nd St Factory PlN Tal bot Rd SN 3rd St RainierAveS 164thAveSETukwilaPkwy SPugetDr NE 4th St S 3rd St S 1 2 9 th S t68thAveSSWSunsetBlvd SW 16th St 116thAveSEN 4th St In t e r u r b a n A v e S WilliamsAveNBronsonWa y N NE7thSt 124thAveSES 7th St SERento n IssaquahRd Rai ni er AveNNewcastle Way CoalCre ek PkwySESW 41st St Ta y l o r P l NW NESunsetBlvdWellsAveNUnionAveNENE 3rd St Hardie Av eSWS180th St Maple V a l l e y H w y 140thAveSES G ra d y W ayS 2 1 s tSt BensonRdSRento n AveS87thAveS128thAveSE148thAveSESW 43rd St SEC arrRd SE 168thSt Beacon Ave S 68thAveSLoganAveN108thAveSEForestDrSE S2ndSt 141s t AveSERainierAveS 156thAveSES E 183rdStBe n s on D r S S124th StS 43rd St Airport Way S W G ra dyW a y SE J o n es RdSunsetBlvdN Puget Dr SESE 204th Way SW 34th StMo n sterRdSW SE 142nd Pl WestValleyHwySSEMayValleyRd SunsetBlvdNS Carr RdHouserWayNNewcastleGolfClubRd S 133rd St WilliamsAveSWellsAveSEMercerWay154thPlSEDuvallAveNELoganAveSMonroeAveNESunsetBlvdNEEdmondsAveNEStevens AveNWRaini er AveSTalbotRdSOakesdaleAveSWTaylorAveNW164thAveSERainierAveSWestVall eyHwyWestValleyHwyParkAveN108thAveSE6 6th A v e S WM ercerWayWMercer W ay LakemontBl vdSE132ndAve SELakeWashingtonBlvdNE140thWaySE East Valley Rd68thAveS³City of Renton Sensitive Areas 0 0.5 10.25 Miles Information Technology - GIS mapsupport@rentonwa.govPrinted on: 11/12/2014 Data Sources: City of Renton, King County This document is a graphic representation, not guaranteed to survey accuracy, and is based on the best informationavailable as of the date shown. This map is intended for City display purposes only. Renton City Limits k Education Fire Station K Valley Medical Center Landslide Hazard Severity Very High High Moderate Unclassified Coordinate System: NAD 1983 HARN StatePlane Washington North FIPS 4601 FeetProjection: Lambert Conformal ConicDatum: North American 1983 HARN PROJECT SITE k k k k k k k k k k k k k k k k k k k k k k k k k k k kk k k k k k k k k k k k k k k k k k k k HoquiamAveNEE Valley Hwy84thAveSNEParkDr SW 7th St SE 128th St SE 192nd StLind Ave SWMainAveSS 132nd St Factory PlN Tal bot Rd SN 3rd St RainierAveS 164thAveSETukwilaPkwy SPugetDr NE 4th St S 3rd St S 1 2 9 th S t68thAveSSWSunsetBlvd SW 16th St 116thAveSEN 4th St In t e r u r b a n A v e S WilliamsAveNBronsonWa y N NE7thSt 124thAveSES 7th St SERento n IssaquahRd Rai ni er AveNNewcastle Way CoalCre ek PkwySESW 41st St Ta y l o r P l NW NESunsetBlvdWellsAveNUnionAveNENE 3rd St Hardie Av eSWS180th St Maple V a l l e y H w y 140thAveSES G ra d y W ayS 2 1 s tSt BensonRdSRento n AveS87thAveS128thAveSE148thAveSESW 43rd St SEC arrRd SE 168thSt Beacon Ave S 68thAveSLoganAveN108thAveSEForestDrSE S2ndSt 141s t AveSERainierAveS 156thAveSES E 183rdStBe n s on D r S S124th StS 43rd St Airport Way S W G ra dyW a y SE J o n es RdSunsetBlvdN Puget Dr SESE 204th Way SW 34th StMo n sterRdSW SE 142nd Pl WestValleyHwySSEMayValleyRd SunsetBlvdNS Carr RdHouserWayNNewcastleGolfClubRd S 133rd St WilliamsAveSWellsAveSEMercerWay154thPlSEDuvallAveNELoganAveSMonroeAveNESunsetBlvdNEEdmondsAveNEStevens AveNWRaini er AveSTalbotRdSOakesdaleAveSWTaylorAveNW164thAveSERainierAveSWestVall eyHwyWestValleyHwyParkAveN108thAveSE6 6th A v e S WM ercerWayWMercer W ay LakemontBl vdSE132ndAve SELakeWashingtonBlvdNE140thWaySE East Valley Rd68thAveS³City of Renton Sensitive Areas 0 0.5 10.25 Miles Information Technology - GIS mapsupport@rentonwa.govPrinted on: 11/12/2014 Data Sources: City of Renton, King County This document is a graphic representation, not guaranteed to survey accuracy, and is based on the best informationavailable as of the date shown. This map is intended for City display purposes only. Renton City Limits k Education Fire Station K Valley Medical Center Steep SlopesPercent Range >15% & <=25% >25% & <=40% >40% & <=90% >90%Coordinate System: NAD 1983 HARN StatePlane Washington North FIPS 4601 FeetProjection: Lambert Conformal ConicDatum: North American 1983 HARN PROJECT SITE Cobalt Geosciences, LLC P.O. Box 82243 Kenmore, Washington 98028 www.cobaltgeo.com (206) 331-1097 November 22, 2021 Mr. Bob Wenzl Tuscany Homes RE: Geotechnical Addendum Proposed Residence 857 Field Avenue NE Renton, Washington In accordance with your authorization, Cobalt Geosciences, LLC has prepared this letter to discuss our plan review. We have reviewed the civil plan sheet C4.01 by Core Design which shows the planned building/road layout and detention system. While large-scale infiltration systems are not feasible, permeable pavements may be utilized for driveway and/or walkway areas provided the following recommendations are incorporated: Subgrades should be stripped of topsoil to expose the weathered glacial till Subgrades should not be compacted or driven on by equipment until area is completed with pavement or concrete Geotechnical engineer to verify soil conditions and grading prior to rock placement to verify gradients and density Minimum 8 inch thick base rock over subgrade (5/8 inch clean angular rock) Minimum 5 inch thick asphalt or concrete, although 6 to 8 inches is more common We can provide additional input upon request. Please notify us if new or existing buildings have basement levels, so that we may provide an underdrain recommendation. Closure The information presented herein is based upon professional interpretation utilizing standard practices and a degree of conservatism deemed proper for this project. We emphasize that this report is valid for this project as outlined above and for the current site conditions and should not be used for any other site. Sincerely, Cobalt Geosciences, LLC Phil Haberman, PE, LG, LEG Principal Cobalt Geosciences, LLC P.O. Box 82243 Kenmore, Washington 98028 www.cobaltgeo.com (206) 331-1097 January 6, 2021 Mr. Bob Wenzl Tuscany Homes RE: Stormwater Feasibility Evaluation Proposed Residence 857 Field Avenue NE Renton, Washington Dear Mr. Wenzl, In accordance with your authorization, Cobalt Geosciences, LLC has prepared this letter to discuss the results of our stormwater feasibility evaluation at the referenced site. The purpose of our evaluation was to determine the feasibility of utilizing infiltration devices for stormwater runoff management. Site and Project Description The site is located at 857 Field Avenue NE in Renton, Washington. The site consists of one rectangular parcel (No. 1437650040) with a total area of about 15,130 square feet. The eastern portion of the property is developed with a residence and driveway. The remainder of the property is undeveloped and vegetated with grasses, bushes/shrubs, and variable diameter evergreen and deciduous trees. The site slope gently downward from east to west at magnitudes of 5 to 10 percent and total relief of about 12 feet. The property is bordered to the north, west, and south by residential parcels and to the east by Field Avenue NE. The project includes subdivision of the property followed by construction of a new residence. We anticipate that the existing residence will remain in place. Stormwater management may include dispersion, detention, or infiltration facilities depending on feasibility. Area Geology The Geologic Map of King County indicates that the site is underlain by Vashon Glacial Till. Vashon Glacial Till is typically characterized by an unsorted, non-stratified mixture of clay, silt, sand, gravel, cobbles and boulders in variable quantities. These materials are typically dense and relatively impermeable. The poor sorting reflects the mixing of the materials as these sediments were overridden and incorporated by the glacial ice. Soil & Groundwater Conditions As part of our evaluation, we excavated two test pits to determine the shallow soil and groundwater conditions, where accessible. January 6, 2021 Page 2 of 3 Stormwater Feasibility Evaluation www.cobaltgeo.com (206) 331-1097 The test pit encountered approximately 6 inches of topsoil and vegetation underlain by approximately 2.5 to 3 feet of loose to medium dense, silty-fine to medium grained sand with gravel (Weathered Glacial Till). These materials were underlain by dense, silty-fine to medium grained sand with gravel (Glacial Till), which continued to the termination depths of the test pits. Groundwater was not encountered in the test pits. Groundwater could be present seasonally perched on the underlying glacial till. Stormwater Management Feasibility The site is underlain by weathered and unweathered glacial till. Unweathered glacial till is nearly impermeable and not suitable for widespread infiltration of stormwater runoff. We performed an infiltration test in TP-1 at a depth of about 3 feet below grade. Following saturation, testing, and application of correction factors for site variability (0.8), influent control (0.9), and testing (0.5), the infiltration rate was 0.2 inches per hour. This is lower than what is considered to be feasible for widespread infiltration. We do not recommend the use of infiltration systems at this site. We recommend either dispersion trenches with vegetated flowpaths or direct connection to City infrastructure. Rain gardens and permeable pavements may be feasible depending on the location and elevation of these systems. We can provide additional input upon request. We should be provided with final plans for review to determine if the intent of our recommendations has been incorporated or if additional modifications are needed. Erosion and Sediment Control Erosion and sediment control (ESC) is used to reduce the transportation of eroded sediment to wetlands, streams, lakes, drainage systems, and adjacent properties. Erosion and sediment control measures should be implemented, and these measures should be in general accordance with local regulations. At a minimum, the following basic recommendations should be incorporated into the design of the erosion and sediment control features for the site: Schedule the soil, foundation, utility, and other work requiring excavation or the disturbance of the site soils, to take place during the dry season (generally May through September). However, provided precautions are taken using Best Management Practices (BMP’s), grading activities can be completed during the wet season (generally October through April). All site work should be completed and stabilized as quickly as possible. Additional perimeter erosion and sediment control features may be required to reduce the possibility of sediment entering the surface water. This may include additional silt fences, silt fences with a higher Apparent Opening Size (AOS), construction of a berm, or other filtration systems. Any runoff generated by dewatering discharge should be treated through construction of a sediment trap if there is sufficient space. If space is limited other filtration methods will need to be incorporated. January 6, 2021 Page 3 of 3 Stormwater Feasibility Evaluation www.cobaltgeo.com (206) 331-1097 Closure The information presented herein is based upon professional interpretation utilizing standard practices and a degree of conservatism deemed proper for this project. We emphasize that this report is valid for this project as outlined above and for the current site conditions, and should not be used for any other site. Sincerely, Cobalt Geosciences, LLC 1/6/21 Phil Haberman, PE, LG, LEG Principal PH/sc Proposed Residences 857 Field Avenue NE Renton, Washington N SITE PLAN FIGURE 1 Cobalt Geosciences, LLCP.O. Box 82243 Kenmore, WA 98028 (206) 331-1097 www.cobaltgeo.com cobaltgeo@gmail.com Subject Property TP-1 TP-2 PT Well-graded gravels, gravels, gravel-sand mixtures, little or no fines Poorly graded gravels, gravel-sand mixtures, little or no fines Silty gravels, gravel-sand-silt mixtures Clayey gravels, gravel-sand-clay mixtures Well-graded sands, gravelly sands, little or no fines COARSE GRAINED SOILS (more than 50% retained on No. 200 sieve) Primarily organic matter, dark in color, and organic odor Peat, humus, swamp soils with high organic content (ASTM D4427)HIGHLY ORGANIC SOILS FINE GRAINED SOILS (50% or more passes the No. 200 sieve) MAJOR DIVISIONS SYMBOL TYPICAL DESCRIPTION Gravels (more than 50% of coarse fraction retained on No. 4 sieve) Sands (50% or more of coarse fraction passes the No. 4 sieve) Silts and Clays(liquid limit lessthan 50) Silts and Clays (liquid limit 50 or more) Organic Inorganic Organic Inorganic Sands with Fines(more than 12%fines) Clean Sands (less than 5%fines) Gravels with Fines (more than 12% fines) Clean Gravels (less than 5% fines) Unified Soil Classification System (USCS) Poorly graded sand, gravelly sands, little or no fines Silty sands, sand-silt mixtures Clayey sands, sand-clay mixtures Inorganic silts of low to medium plasticity, sandy silts, gravelly silts, or clayey silts with slight plasticity Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays Organic silts and organic silty clays of low plasticity Inorganic silts, micaceous or diatomaceous fine sands or silty soils, elastic silt Inorganic clays of medium to high plasticity, sandy fat clay, or gravelly fat clay Organic clays of medium to high plasticity, organic silts Moisture Content Definitions Grain Size Definitions Dry Absence of moisture, dusty, dry to the touch Moist Damp but no visible water Wet Visible free water, from below water table Grain Size Definitions Description Sieve Number and/or Size Fines <#200 (0.08 mm) Sand -Fine -Medium -Coarse Gravel -Fine -Coarse Cobbles Boulders #200 to #40 (0.08 to 0.4 mm) #40 to #10 (0.4 to 2 mm) #10 to #4 (2 to 5 mm) #4 to 3/4 inch (5 to 19 mm) 3/4 to 3 inches (19 to 76 mm) 3 to 12 inches (75 to 305 mm) >12 inches (305 mm) Classification of Soil Constituents MAJOR constituents compose more than 50 percent, by weight, of the soil. Major constituents are capitalized (i.e., SAND). Minor constituents compose 12 to 50 percent of the soil and precede the major constituents (i.e., silty SAND). Minor constituents preceded by “slightly” compose 5 to 12 percent of the soil (i.e., slightly silty SAND). Trace constituents compose 0 to 5 percent of the soil(i.e., slightly silty SAND, trace gravel). Relative Density Consistency (Coarse Grained Soils) (Fine Grained Soils) N, SPT, Relative Blows/FT Density 0 - 4 Very loose 4 - 10 Loose 10 - 30 Medium dense 30 - 50 Dense Over 50 Very dense N, SPT, Relative Blows/FT Consistency Under 2 Very soft 2 - 4 Soft4 - 8 Medium stiff8 - 15 Stiff15 - 30 Very stiff Over 30 Hard Cobalt Geosciences, LLCP.O. Box 82243Kenmore, WA 98028(206) 331-1097 www.cobaltgeo.com cobaltgeo@gmail.com Soil Classification Chart Figure C1 Test Pit Logs Cobalt Geosciences, LLCP.O. Box 82243 Kenmore, WA 98028 (206) 331-1097 www.cobaltgeo.com cobaltgeo@gmail.com Proposed Residence 857 Field Avenue NE Renton, Washington Test Pit TP-1 Date: December 4, 2020 Contractor: Client provided Depth: 5.5’ Elevation: Logged By: PH Checked By: SC Groundwater: None Material Description Moisture Content (%)PlasticLimit Liquid Limit 10 20 30 400 50 DCP Equivalent N-Value 10 Test Pit TP-2 Date: December 4, 2020 Contractor: Client provided Depth: 5.5’ Elevation: Logged By: PH Checked By: SC Groundwater: None Material Description Moisture Content (%)PlasticLimit Liquid Limit 10 20 30 400 50 1 2 3 4 5 6 DCP Equivalent N-Value 7 8 9 10 Loose to medium dense, silty-fine to medium grained sand with gravel, reddish brown to yellowish brown, moist. (Weathered Glacial Till) SM End of Test Pit 5.5’ Dense, silty-fine to medium grained sand with gravel, grayish brown, moist. (Glacial Till) -Locally cemented SM Topsoil/Grass Material Description Moisture Content (%)Plastic Limit Liquid Limit 10 20 30 400 50 1 2 3 4 5 6 DCP Equivalent N-Value 7 8 9 Loose to medium dense, silty-fine to medium grained sand with gravel, reddish brown to yellowish brown, moist. (Weathered Glacial Till) SM End of Test Pit 5.5’ Dense, silty-fine to medium grained sand with gravel, grayish brown, moist. (Glacial Till) -Locally cemented SM Topsoil/Grass