Loading...
HomeMy WebLinkAboutRS_Technical_Information_Report_240903_v1.pdf Western Washington Division Eastern Washington Division 165 NE Juniper St., Ste 201, Issaquah, WA 98027 407 Swiftwater Blvd, Cle Elum, WA 98922 Phone: (425) 392-0250 Fax: (425) 391-3055 Phone: (509) 674-7433 Fax: (509) 674-7419 www.EncompassES.net PRELIMINARY TECHNICAL INFORMATION REPORT For 2811 NE 13th St Unit Lot Short Plat 2811 NE 13th St Renton, WA 98056 October 20, 2023 Revised: August 29th 2024 10/29/2023 Prepared by: Samuel Salo Encompass Engineering Job No. 23531 Prepared For: Amani Imran 212 Chelan Ave NE Renton, WA 98059 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | i Table of Contents I. PROJECT OVERVIEW ................................................................................................................ 1 II. CONDITIONS AND REQUIREMENTS SUMMARY ...................................................................... 6 III. OFF-SITE ANALYSIS ................................................................................................................ 10 IV. FLOW CONTROL, LOW IMPACT DEVELOPMENT AND WATER QUALITY FACILITY ANALYSIS AND DESIGN ........................................................................................................................... 14 V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN ..................................................................... 17 VI. SPECIAL REPORTS AND STUDIES ............................................................................................ 17 VII. OTHER PERMITS ..................................................................................................................... 17 VIII. CSWPP ANALYSIS AND DESIGN .............................................................................................. 17 IX. BOND QUANTITIES, FACILITY SUMMARIES AND DECLARATION of COVENANT ................... 17 X. OPERATION AND MAINTENANCE MANUAL .......................................................................... 17 List of Figures Figure 1 – TIR Worksheet Figure 2 – Vicinity Map Figure 3 – Soils Map and Legend Figure 4 – Existing Conditions Map Figure 5 – Developed Conditions Map Figure 6 – Drainage Review Flow Chart Figure 7 – Downstream Map Appendix A Geotechnical Report by Terra Associates, Inc. dated October 16, 2023 Appendix B WWHM Output CITY OF RENTON SURFACE WATER DESIGN MANUAL 2017 City of Renton Surface Water Design Manual 12/12/2016 8-A-1 REFERENCE 8-A 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 __________________________ CED Permit # ________________________ Location Township ________________ Range __________________ Section _________________ Site Address __________________________ _____________________________________ Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS  Land Use (e.g., Subdivision / Short Subd.)  Building (e.g., M/F / Commercial / SFR)  Grading  Right-of-Way Use  Other _______________________  DFW HPA  COE 404  DOE Dam Safety  FEMA Floodplain  COE Wetlands  Other ________  Shoreline Management  Structural Rockery/Vault/_____  ESA Section 7 Part 5 PLAN AND REPORT INFORMATION Technical Information Report Site Improvement Plan (Engr. Plans) Type of Drainage Review (check one): Date (include revision dates): Date of Final:  Full  Targeted  Simplified  Large Project  Directed __________________ __________________ __________________ Plan Type (check one): Date (include revision dates): Date of Final:  Full  Modified  Simplified __________________ __________________ __________________ REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 12/12/2016 2017 City of Renton Surface Water Design Manual 8-A-2 Part 6 SWDM ADJUSTMENT APPROVALS Type (circle one): Standard / Blanket Description: (include conditions in TIR Section 2) ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ Approved Adjustment No. ______________________ Date of Approval: _______________________ Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes / No Start Date: _______________________ Completion Date: _______________________ Describe: _________________________________ _________________________________________ _________________________________________ Re: SWDM 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 ______________________  _____________________________________ REFERENCE 8-A: TECHNICAL INFORMATION REPORT (TIR) WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2017 City of Renton Surface Water Design Manual 12/12/2016 Ref 8-A-3 Part 10 SOILS Soil Type ______________________ ______________________ ______________________ ______________________ Slopes ________________________ ________________________ ________________________ ________________________ Erosion Potential _________________________ _________________________ _________________________ _________________________  High Groundwater Table (within 5 feet)  Other ________________________________  Sole Source Aquifer  Seeps/Springs  Additional Sheets Attached 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) Standard: _______________________________ or Exemption Number: ____________ On-site 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: _________________________ REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 12/12/2016 2017 City of Renton Surface Water Design Manual 8-A-4 Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) 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. _______________________ Special Requirements (as applicable): Area Specific Drainage Requirements Type: SDO / MDP / BP / 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: 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: REFERENCE 8-A: TECHNICAL INFORMATION REPORT (TIR) WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2017 City of Renton Surface Water Design Manual 12/12/2016 Ref 8-A-5 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  Control Pollutants  Protect Existing and Proposed BMPs/Facilities  Maintain Protective 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 BMPs/Facilities, restore operation of BMPs/Facilities as necessary  Flag limits of sensitive areas 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  On-site BMPs  Other ________________ ________________ ________________ ________________ ________________ ________________  Vegetated Flowpath  Wetpool  Filtration  Oil Control  Spill Control  On-site BMPs  Other ________________ ________________ ________________ ________________ ________________ ________________ ________________ 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 _______________________________ REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 12/12/2016 2017 City of Renton Surface Water Design Manual 8-A-6 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 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 1 I. PROJECT OVERVIEW Project: 2811 NE 13th St Short Plat Site Address: 2811 NE 13th Street, Renton, WA 98056 (See Vicinity Map) Tax Parcel #: 722780-1700 Zoning District: R-14 (Residential 14 DU/Acre) Site Area: 15,800 SF (0.36 AC) Figure 2: Vicinity Map Pre-developed Site Conditions The project site is located in the City of Renton on a 15,800 SF (0.36 AC) lot that is zoned R-14 (Residential 14 DU/Acre). The site is accessed from NE 13th Street, east of the intersection of Harrington Ave NE and NE 13th Street. The site is bordered to the north by NE 13th Street, to the east and south by single-family residences, and to the west by a multifamily development. The existing site includes a single-family residence, detached garage, with gravel and concrete driveway access to NE 13th St. Apart from these existing structures, the site is primarily covered with lawn area with a grouping of trees in the southern portion of the site. The site gently slopes to the southwest at 1-2%. An Existing Conditions Map is included as Figure 4 at the end of this Section. 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 2 Critical Areas According to King County iMap and the City of Renton Maps, there are no critical areas located on or adjacent to the subject site. Soils Per the US Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) Web Soil Survey (WSS) information, the entire project site is underlain with Arents, Alderwood material, 6 to 15 percent slopes (See Figure 3 on the following page). The Geotechnical Report prepared by Terra Associates, Inc. (Appendix A) states that the site is underlain by dense silty sand to silty sand with varying gravel and cobble content. Limited infiltration is feasible with shallow gravel infiltration trenches with an underdrain/overflow system. Figure 3: Soil Map and Legend 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 3 Developed Site Conditions The project proposes the development of two townhouse structures containing a total of five units within the 15,800 SF (0.36 AC) parcel. The total proposed roof area is 4,483 SF. Additionally, 1,382 SF of on-site driveway, and 1,406 SF of on-site walkways is proposed. A 16’ alley is proposed along the western site boundary with 12’ paved. The area of this alley is 2,448 SF. This area will include sewer, water and storm utility extensions from NE 13th St. The total proposed on-site impervious area for the project is 9,719 SF, which is approximately 61.5% of the site area. The parcel is zoned R-14 (Residential 14 DU/Acre), which allows for a maximum building coverage of 65% and a maximum impervious surface coverage of 80%. The proposed improvements fall below the thresholds per zoning requirements. Frontage improvements are also proposed, including vertical curb/gutter, 8’ planter strip, and 5’ sidewalk. 1.5’ will be dedicated from the site to the ROW. Stormwater runoff from the proposed townhouse units will be mitigated with feasible on-site infiltration BMPs before being collected and conveyed to a proposed storm system on NE 13th St. Section II and Section IV of this TIR for additional discussion on stormwater BMPs. A Developed Conditions Map is provided as Figure 5 at this end of this Section. NE 13TH STHARRINGTON AVE NE NE 13TH STIN COMPLIANCE WITH CITY OF RENTON STANDARDSKnow what'sCallbelow.before you dig.REncompassEastern Washington Division407 Swiftwater Blvd. ▪ Cle Elum, WA 98922 ▪ Phone: (509) 674-7433Western Washington Division165 NE Juniper Street, Suite 201 ▪ Issaquah, WA 98027 ▪ Phone: (425) 392-0250ENGINEERING & SURVEYINGNORTH MATCHLINE (SEE WINDOW TO RIGHT)EXISTING ON-SITE IMPERVIOUS COVERAGE:MATCH LINE (SEE WINDOW TO LEFT)EXISTING OFF-SITE IMPERVIOUS COVERAGE:2811 TOWNHOMES 2811 TOWNHOMES EXISTING CONDITIONSPRELIMINARY CIVIL PLANSARMANI IMRAN2811 TOWNHOMES NE 13TH STLOT 1LOT 2LOT 3LOT 4LOT 5COMMOONOPEN SPACETRACT A 16'PUBLIC ROWTRACT A 16'PUBLIC ROWNORTH PROPOSED IMPERVIOUS COVERAGE:IN COMPLIANCE WITH CITY OF RENTON STANDARDSKnow what'sCallbelow.before you dig.REncompassEastern Washington Division407 Swiftwater Blvd. ▪ Cle Elum, WA 98922 ▪ Phone: (509) 674-7433Western Washington Division165 NE Juniper Street, Suite 201 ▪ Issaquah, WA 98027 ▪ Phone: (425) 392-0250ENGINEERING & SURVEYING2811 TOWNHOMES 2811 TOWNHOMES DEVELOPED CONDITIONSPRELIMINARY CIVIL PLANSARMANI IMRAN2811 TOWNHOMES 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 6 II. CONDITIONS AND REQUIREMENTS SUMMARY The 2022 City of Renton Surface Water Design Manual (RSWDM) was utilized to determine and address all core and special requirements. Based on the criteria specified in Figure 1.1.2.A of the RSWDM, the project falls under Full Drainage Review. Per Section 1.1.2.4 of the RSWDM, the project must meet all nine (9) core and all six (6) special requirements. See Figure 6 below for more information on how the type of drainage review was determined. Figure 6: Drainage Review Flow Chart 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 7 Core Requirements Core Requirement #1: Discharge at the Natural Location The proposed development runoff will ultimately follow existing drainage patterns which connect to the City of Renton stormwater system southwest of the site. Refer to the Level 1 Downstream Analysis in Section III of this TIR for a complete description of the existing drainage paths. Core Requirement #2: Downstream Analysis A Level 1 Downstream analysis has been completed for the site and no existing or potential problems have been identified. This analysis is included in Section III of this TIR. Core Requirement #3: Flow Control Facilities Based on the City of Renton’s flow control application map, the project site is located within the Peak Rate Flow Control Standard (Existing Site Conditions). Flow control facilities are required to match the developed peak discharge rates to existing site conditions peak discharge rates for 2-, 10- and 100-year return periods. The proposed stormwater BMPs result in a 0.0523 CFS increase in the 100-year flow using 15- minutes time steps. This is below the allowable threshold of a 0.15 CFS maximum increase per Section 1.2.3.1.A of the RSWDM; therefore, the project meets flow control exemption 2. No formal flow control facilities are proposed at this time; however, flow control BMPs will be implemented as described in Core Requirement #9. Please refer to Section IV of this TIR for additional discussion. Core Requirement #4: Conveyance System Conveyance in compliance with the requirements detailed in Section 1.2.4.1 of the City of Renton 2022 SWDM will be provided with final engineering. Core Requirement #5: Construction Stormwater Pollution Prevention A temporary erosion and sediment control (TESC) plan providing details on best management practices (BMPs) to be implemented during construction is included in the engineering plan set. A Construction Stormwater Pollution Prevention Plan (CSWPPP) will be provided with final engineering. Please refer to Section VIII of this TIR for additional discussion. Core Requirement #6: Maintenance and Operations An Operation and Maintenance Manual will be provided with final engineering. Core Requirement #7: Financial Guarantees and Liability The owner will arrange for any financial guarantees and liabilities required by the permit. Core Requirement #8: Water Quality Facilities In accordance with Section 1.2.8.1.A of the RSWDM, Basic Water Quality Treatment is not required for this project as new plus replaced pollution generating impervious surfaces (PGIS) do not exceed 5,000 SF, meeting exemption 1. 3,870 SF of on-site PGIS will be created or replaced as a result of this project. 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 8 Core Requirement #9: Flow Control BMPs This project is classified as a small subdivision; therefore, it is subject to the Small Subdivision Project BMP Requirements detailed in Section 1.2.9.3.1 in the RSWDM. Although implementation of BMPs is not required until building permit application, BMPs have been considered for the future improvements based on Section 1.2.9.2 and of the RSWDM. See Section IV of this TIR for further discussion and flow control analysis. Impervious Surface BMPs Full Dispersion: Infeasible. The space required for a 100-foot native vegetated flowpath segment is not available on these sites. Full Infiltration: Infeasible. The Geotechnical Report prepared by Terra Associates, Inc. (Appendix A) states that the site is underlain by dense silty sand to silty sand with gravel. Only shallow, limited infiltration facilities with overflow devices are recommended in these soils. Limited Infiltration: Feasible. A shallow gravel infiltration trench will be used for units 4 & 5 in the southwest corner of the site with an overflow connected to the on-site stormwater system. Using a conservative USDA soil classification of loam, a 52-foot long, 2-foot wide trench can mitigate up to 1,000 SF of impervious area in rainfall region SeaTac 1.0 and less. This equates to 104 SF of gravel trench per 1,000 SF of impervious. A 10’x20’ trench is proposed to mitigate 1,768 SF of rooftop area. This facility is sizes to mitigate up to (200/104) x 1,000=1,923 SF of impervious. An overflow system will be included which is connected to the proposed storm system in the ROW. Rain Gardens/Bioretention: Infeasible. The site plan does not allow the space or necessary infiltration rate required for these facilities. Permeable Pavement: Infeasible, The soils on site are not suitable for permeable pavement. Basic Dispersion: Infeasible. Stormwater surface discharge to the south would negatively impact downslope residences to the south. Reduced Impervious Surface Credit: Infeasible. The proposed on-site impervious surface of 9,717 SF exceeds the threshold of 4,000 SF, which is required for eligibility for a reduced impervious surface credit. Native Growth Retention Credit: Infeasible. The necessary area to allow for 3.5 SF of native vegetated surface for every SF of impervious surface is not available on any of the lots. Tree Retention Credit: Feasible for Lots 1-3. At least 30% of significant trees will be retained per Department of Community and Economic Development notes in the Pre-Application Meeting. Soil Amendment: Feasible for Lots 1-3. All disturbed, pervious areas of the project will meet soil amendment requirements as detailed in Section C.2.13 of the RSWDM. BMPs must be implemented, at minimum, for an impervious area equal to at least 20% of the site/lot for site/lot sizes between 11,000 and 22,000 SF. This project proposes to implement BMPs 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 9 for a total of 4,971 SF, which is 31.5% of the lot. Therefore, this project meets this minimum criteria. Special Requirements Special Requirement #1: Other Adopted Area-Specific Requirements Critical Drainage Area – N/A Master Drainage Plan – N/A Basin Plan – N/A Lake management Plan – N/A Shared Facility Drainage Plan – N/A Special Requirement #2: Flood Hazard Area Delineation The limits of this project do not lie within a delineated FEMA 100-year floodplain. Special Requirement #3: Flood Protection Facilities This project does not rely on or propose to modify/construct a new flood protection facility. Special Requirement #4: Source controls The project is a single-family residential development; therefore, this requirement is not applicable. Special Requirement #5: Oil Control This project is not considered high-use in need of oil control. Special Requirement #6: Aquifer Protection Area The site is not located within an Aquifer Protection Area. 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 10 III. OFF-SITE ANALYSIS A Level 1 Downstream analysis has been conducted per the requirements in Section 1.2.2.1 of the RSWDM. Please see Tasks 1 through 4 below for a summary of the results. Task 1: Define and Map the Study Area The area of analysis extends from the site discharge point (southwestern side of the parcel) to approximately a quarter-mile downstream. A Downstream Map is provided in Figure 7 below. Figure 7: Downstream Map Task 2: Review All Available Information on the Study Area Per King County resources, there have been no significant drainage complaints within a quarter mile downstream of the site. Task 3: Field Inspect the Study Area A field inspection was performed by Encompass Engineering & Surveying on July 7th, 2022. Please refer to Task 4 for a detailed description of the downstream drainage system and analysis. Task 4: Describe the Drainage System Runoff leaves the site through one NDA, creating a single TDA for the site. Stormwater starts by sheet flowing downhill through lawn surfaces towards the southwestern side of the parcel (A). Once exiting the 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 11 site, the stormwater continues to sheet flow to the southwest by following the natural topography through neighboring lots. After about 400 FT, the runoff accumulates at the intersection of NE 12th Street and Harrington Ave NE and enters a type 1 catch basin located at the northeastern corner of the intersection (B). After entering the stormwater system, the runoff is conveyed to the south side of NE 12th Street to a type 2 catch basin location (C). From here, the stormwater is conveyed through the system to the west for 750 FT until reaching Edmonds Ave NE (D). After reaching Edmonds Ave NE, the runoff begins to head south until reaching the ¼ mile downstream limit (E). Images of the downstream flow path can be found below. Element B – Runoff accumulates at a type 1 CB at NE 12th Street and Harrington Ave NE 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 12 Element C - Runoff conveyed to south side of NE 12th Street (type 2 CB location) Element D – Stormwater system turns to the south along Edmonds Ave NE 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 13 Element E – Stormwater heads south along Edmonds Ave NE until ¼ mile downstream limit 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 14 IV. FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN Part A: Existing Site Hydrology The existing site includes a single-family residence, detached garage, with gravel and concrete driveway access to NE 13th St. Apart from these existing structures, the site is primarily covered with lawn area with a grouping of trees in the southern portion of the site. The site gently slopes to the southwest at 1-2%. The property is located in the East Lake Washington – Renton drainage basin, within the Cedar River/Lake Washington watershed. All stormwater runoff from the site ultimately discharges into the Cedar River. See full downstream analysis in Section III of this Preliminary Technical Information Report (TIR). The Geotechnical Report prepared by Terra Associates, Inc. (Appendix A) states that the site is underlain by dense silty sand to silty sand with varying gravel and cobble content. Limited infiltration is feasible with shallow gravel infiltration trenches with an underdrain/overflow system. WWHM 2012 was used to model the existing condition within the 15,800 SF (0.36 AC) limits of disturbance using existing surfaces found on site including rooftop, driveway, lawn and walkways. Part B: Developed Site Hydrology The project proposes the development of two townhouse structures with a total of 4,377 SF of roof area containing a total of five units within the 15,800 SF (0.36 AC) parcel. A 16’ alley is proposed along the western site boundary with 12’ paved. A total of 3,203 SF of on-site permeable pavement driveway, and 1,121 SF of on-site walkways is proposed. The total proposed on-site impervious area for the project is 8,701 SF. Additionally, frontage improvements at NE 13th St will include vertical curb/gutter, 8’ planter strip, and 5’ sidewalk. 1.5’ will be dedicated from the site to the ROW. The COR storm system on Harrington Ave to the west of the project site will be extended to the east to the project frontage. Stormwater runoff from the proposed townhouse units will be mitigated with feasible on-site infiltration BMPs before being collected and conveyed to a proposed storm system on NE 13th St. T Feasible. A shallow gravel infiltration trench will be used for units 4 & 5 in the southwest corner of the site with an overflow connected to the on-site stormwater system. Permeable pavement with an underdrain is proposed for all 3,203 SF on-site driveway areas. The underdrain will be connected to the proposed storm system in the ROW. WWHM 2012 was used to model the proposed condition as follows: WWHM Model (Pre-Developed) Area Description Size Roof Tops, Flat 2,736 SF (0.06 AC) Driveway, Flat 1,470 SF (0.03 AC) C, Lawn, Flat 11,594 SF (0.27 AC) TOTAL LIMITS OF DISTURBANCE 15,800 SF (0.36 AC) 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 15 WWHM Model (Mitigated) Area Description Size Roof Tops, Flat 4,377 SF (0.10 AC) Driveway, Flat 3,203 SF (0.07 AC) Walkways, Flat 1,121 SF (0.03 AC) C, Lawn, Flat 7,099 SF (0.16 AC) TOTAL LIMITS OF DISTURBANCE 15,800 SF (0.36 AC) Part C: Performance Standards Based on the City of Renton’s flow control map, the project site is located within the Peak Rate Flow Control Standard (Existing Site Conditions). Flow control facilities are required to match the developed peak discharge rates to existing site conditions peak discharge rates for 2-, 10- and 100-year return periods. However, the site meets flow control exemption 2 per Section 1.2.3.1.A of the RSWDM, and flow control facilities are not required. In addition, the site is smaller than 22,000 SF. Therefore, the site is subject to Small Lot BMP Requirements detailed in Section 1.2.9.2.2 of the RSWDM. The site falls within a Basic Water Quality treatment area in accordance with Section 1.2.8.1.A of the RSWDM, however new plus replaced impervious pollution generating areas within the project site is under 5,000 SF and therefore water quality treatment is not required. Part D: Flow Control System As shown in the table on the following page, the proposed stormwater BMPs result in a 0.0338 CFS increase in the 100-year flow using 15-minutes time steps. This is below the allowable threshold of a 0.15 CFS maximum increase per Section 1.2.3.1.B of the RSWDM; therefore, the project meets flow control exemption 2. No formal flow control facilities are proposed at this time; however, flow control BMPs will be implemented as described in Core Requirement #9 in Section II of this TIR. Please refer to Appendix B for a copy of the full WWHM data output. 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 16 Part E: Water Quality System In accordance with Section 1.2.8.1.A of the RSWDM, Basic Water Quality Treatment is not required for this project as new plus replaced pollution generating impervious surfaces (PGIS) do not exceed 5,000 SF, meeting exemption 1. 3,203 SF of PGIS will be created or replaced as a result of this project. 2811 NE 13th St Short Plat Preliminary Technical Information Report 08/29/2024 P a g e | 17 V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN A conveyance system analysis will be provided with final engineering. VI. SPECIAL REPORTS AND STUDIES · Geotechnical Report by Terra Associates, Inc. dated October 16, 2023 VII. OTHER PERMITS · Civil Construction Permit · Building Permits · Right-of-Way Use Permit VIII. CSWPP ANALYSIS AND DESIGN A CSWPPP will be provided with final engineering. IX. BOND QUANTITIES, FACILITY SUMMARIES AND DECLARATION of COVENANT Bond Quantities, Facility Summary and Declaration of Covenant to be provided with final engineering. X. OPERATION AND MAINTENANCE MANUAL An Operation and Maintenance Manual to be provided with final engineering. Appendix A Geotechnical Report by Terra Associates, Inc. dated October 16, 2023 Appendix B WWHM Output WWHM2012 PROJECT REPORT 23531 WWHM 8/30/2024 10:01:14 AM Page 2 General Model Information WWHM2012 Project Name:23531 WWHM Site Name: Site Address: City: Report Date:8/30/2024 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2024/06/28 Version:4.3.1 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year 23531 WWHM 8/30/2024 10:01:14 AM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 0.27 Pervious Total 0.27 Impervious Land Use acre ROOF TOPS FLAT 0.06 DRIVEWAYS FLAT 0.03 Impervious Total 0.09 Basin Total 0.36 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 1 POC 1 23531 WWHM 8/30/2024 10:01:14 AM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 0.14 Pervious Total 0.14 Impervious Land Use acre ROADS MOD 0.06 ROOF TOPS FLAT 0.1 DRIVEWAYS FLAT 0.03 SIDEWALKS FLAT 0.03 Impervious Total 0.22 Basin Total 0.36 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 1 POC 1 23531 WWHM 8/30/2024 10:01:14 AM Page 5 Routing Elements Predeveloped Routing 23531 WWHM 8/30/2024 10:01:14 AM Page 6 Mitigated Routing 23531 WWHM 8/30/2024 10:01:14 AM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.27 Total Impervious Area:0.09 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.14 Total Impervious Area:0.22 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.053187 5 year 0.077386 10 year 0.09571 25 year 0.121601 50 year 0.142958 100 year 0.166157 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.095676 5 year 0.124803 10 year 0.14551 25 year 0.17335 50 year 0.195346 100 year 0.21845 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.084 0.133 1950 0.087 0.124 1951 0.051 0.082 1952 0.031 0.062 1953 0.030 0.070 1954 0.042 0.078 1955 0.044 0.088 1956 0.044 0.084 1957 0.061 0.101 1958 0.038 0.077 23531 WWHM 8/30/2024 10:03:39 AM Page 8 1959 0.029 0.076 1960 0.055 0.087 1961 0.049 0.083 1962 0.032 0.069 1963 0.048 0.084 1964 0.041 0.076 1965 0.066 0.105 1966 0.034 0.065 1967 0.088 0.117 1968 0.071 0.138 1969 0.059 0.096 1970 0.049 0.090 1971 0.059 0.108 1972 0.083 0.119 1973 0.029 0.062 1974 0.059 0.102 1975 0.063 0.102 1976 0.045 0.080 1977 0.042 0.076 1978 0.050 0.097 1979 0.054 0.129 1980 0.098 0.142 1981 0.051 0.097 1982 0.096 0.144 1983 0.051 0.108 1984 0.039 0.070 1985 0.053 0.097 1986 0.051 0.083 1987 0.056 0.124 1988 0.029 0.073 1989 0.036 0.101 1990 0.163 0.204 1991 0.112 0.157 1992 0.039 0.070 1993 0.028 0.064 1994 0.024 0.063 1995 0.044 0.086 1996 0.073 0.106 1997 0.059 0.095 1998 0.046 0.089 1999 0.122 0.202 2000 0.054 0.095 2001 0.042 0.100 2002 0.084 0.128 2003 0.065 0.108 2004 0.110 0.189 2005 0.051 0.083 2006 0.049 0.077 2007 0.148 0.184 2008 0.110 0.152 2009 0.065 0.116 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.1627 0.2035 2 0.1485 0.2022 3 0.1219 0.1890 23531 WWHM 8/30/2024 10:03:39 AM Page 9 4 0.1123 0.1840 5 0.1100 0.1571 6 0.1099 0.1519 7 0.0979 0.1439 8 0.0959 0.1421 9 0.0876 0.1378 10 0.0866 0.1330 11 0.0842 0.1288 12 0.0841 0.1277 13 0.0826 0.1239 14 0.0732 0.1238 15 0.0711 0.1193 16 0.0657 0.1169 17 0.0654 0.1155 18 0.0648 0.1085 19 0.0634 0.1081 20 0.0611 0.1078 21 0.0593 0.1063 22 0.0591 0.1053 23 0.0589 0.1022 24 0.0589 0.1018 25 0.0565 0.1011 26 0.0547 0.1006 27 0.0538 0.0997 28 0.0536 0.0973 29 0.0526 0.0973 30 0.0514 0.0966 31 0.0514 0.0958 32 0.0513 0.0953 33 0.0509 0.0951 34 0.0509 0.0898 35 0.0499 0.0887 36 0.0490 0.0882 37 0.0490 0.0871 38 0.0488 0.0859 39 0.0475 0.0844 40 0.0459 0.0839 41 0.0452 0.0835 42 0.0444 0.0833 43 0.0443 0.0831 44 0.0439 0.0816 45 0.0424 0.0795 46 0.0424 0.0781 47 0.0417 0.0773 48 0.0414 0.0766 49 0.0386 0.0764 50 0.0386 0.0758 51 0.0381 0.0756 52 0.0364 0.0728 53 0.0339 0.0705 54 0.0320 0.0704 55 0.0314 0.0700 56 0.0301 0.0688 57 0.0294 0.0654 58 0.0293 0.0636 59 0.0291 0.0633 60 0.0281 0.0619 61 0.0243 0.0617 23531 WWHM 8/30/2024 10:03:39 AM Page 10 23531 WWHM 8/30/2024 10:03:39 AM Page 11 Duration Flows The Duration Matching Failed Flow(cfs)Predev Mit Percentage Pass/Fail 0.0266 1424 9298 652 Fail 0.0278 1241 8301 668 Fail 0.0289 1085 7394 681 Fail 0.0301 935 6624 708 Fail 0.0313 827 5972 722 Fail 0.0325 717 5358 747 Fail 0.0336 623 4838 776 Fail 0.0348 559 4380 783 Fail 0.0360 510 3948 774 Fail 0.0372 473 3578 756 Fail 0.0383 418 3255 778 Fail 0.0395 381 2954 775 Fail 0.0407 346 2671 771 Fail 0.0419 317 2440 769 Fail 0.0430 290 2248 775 Fail 0.0442 267 2053 768 Fail 0.0454 246 1866 758 Fail 0.0466 222 1706 768 Fail 0.0478 207 1577 761 Fail 0.0489 194 1454 749 Fail 0.0501 177 1331 751 Fail 0.0513 162 1228 758 Fail 0.0525 150 1128 752 Fail 0.0536 139 1042 749 Fail 0.0548 128 958 748 Fail 0.0560 120 885 737 Fail 0.0572 115 819 712 Fail 0.0583 109 764 700 Fail 0.0595 99 716 723 Fail 0.0607 97 661 681 Fail 0.0619 94 606 644 Fail 0.0630 90 565 627 Fail 0.0642 84 532 633 Fail 0.0654 76 493 648 Fail 0.0666 70 468 668 Fail 0.0677 67 436 650 Fail 0.0689 63 413 655 Fail 0.0701 61 392 642 Fail 0.0713 57 375 657 Fail 0.0724 54 355 657 Fail 0.0736 52 340 653 Fail 0.0748 48 321 668 Fail 0.0760 47 300 638 Fail 0.0771 45 281 624 Fail 0.0783 40 263 657 Fail 0.0795 39 250 641 Fail 0.0807 39 232 594 Fail 0.0818 38 218 573 Fail 0.0830 37 212 572 Fail 0.0842 35 194 554 Fail 0.0854 33 183 554 Fail 0.0865 31 175 564 Fail 0.0877 29 168 579 Fail 0.0889 27 160 592 Fail 23531 WWHM 8/30/2024 10:03:39 AM Page 12 0.0901 25 154 616 Fail 0.0912 24 143 595 Fail 0.0924 24 133 554 Fail 0.0936 22 129 586 Fail 0.0948 20 125 625 Fail 0.0959 19 120 631 Fail 0.0971 18 117 650 Fail 0.0983 16 109 681 Fail 0.0995 15 103 686 Fail 0.1006 14 98 700 Fail 0.1018 14 90 642 Fail 0.1030 14 86 614 Fail 0.1042 14 84 600 Fail 0.1053 13 82 630 Fail 0.1065 12 78 650 Fail 0.1077 10 77 770 Fail 0.1089 10 71 710 Fail 0.1100 8 69 862 Fail 0.1112 8 65 812 Fail 0.1124 7 64 914 Fail 0.1136 7 62 885 Fail 0.1147 5 60 1200 Fail 0.1159 4 57 1425 Fail 0.1171 4 55 1375 Fail 0.1183 4 54 1350 Fail 0.1195 3 47 1566 Fail 0.1206 3 45 1500 Fail 0.1218 3 45 1500 Fail 0.1230 2 40 2000 Fail 0.1242 2 37 1850 Fail 0.1253 2 35 1750 Fail 0.1265 2 35 1750 Fail 0.1277 2 33 1650 Fail 0.1289 2 32 1600 Fail 0.1300 2 29 1450 Fail 0.1312 2 29 1450 Fail 0.1324 2 28 1400 Fail 0.1336 2 25 1250 Fail 0.1347 2 24 1200 Fail 0.1359 2 23 1150 Fail 0.1371 2 22 1100 Fail 0.1383 2 21 1050 Fail 0.1394 2 20 1000 Fail 0.1406 2 20 1000 Fail 0.1418 2 20 1000 Fail 0.1430 2 17 850 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. 23531 WWHM 8/30/2024 10:03:39 AM Page 13 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. 23531 WWHM 8/30/2024 10:03:39 AM Page 14 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. 23531 WWHM 8/30/2024 10:03:40 AM Page 15 Appendix Predeveloped Schematic 23531 WWHM 8/30/2024 10:04:25 AM Page 16 Mitigated Schematic 23531 WWHM 8/30/2024 10:05:09 AM Page 17 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 23531 WWHM.wdm MESSU 25 Pre23531 WWHM.MES 27 Pre23531 WWHM.L61 28 Pre23531 WWHM.L62 30 POC23531 WWHM1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 IMPLND 4 IMPLND 5 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 16 C, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 16 0 0 4 0 0 0 0 0 0 0 0 0 1 9 23531 WWHM 8/30/2024 10:05:09 AM Page 18 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 16 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 16 0 4.5 0.03 400 0.05 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 16 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 16 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 4 ROOF TOPS/FLAT 1 1 1 27 0 5 DRIVEWAYS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 4 0 0 1 0 0 0 5 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 4 0 0 4 0 0 0 1 9 5 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 4 0 0 0 0 0 5 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 4 400 0.01 0.1 0.1 5 400 0.01 0.1 0.1 23531 WWHM 8/30/2024 10:05:09 AM Page 19 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 4 0 0 5 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 4 0 0 5 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 16 0.27 COPY 501 12 PERLND 16 0.27 COPY 501 13 IMPLND 4 0.06 COPY 501 15 IMPLND 5 0.03 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 23531 WWHM 8/30/2024 10:05:09 AM Page 20 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN 23531 WWHM 8/30/2024 10:05:09 AM Page 21 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 23531 WWHM.wdm MESSU 25 Mit23531 WWHM.MES 27 Mit23531 WWHM.L61 28 Mit23531 WWHM.L62 30 POC23531 WWHM1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 IMPLND 2 IMPLND 4 IMPLND 5 IMPLND 8 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 16 C, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR 23531 WWHM 8/30/2024 10:05:09 AM Page 22 # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 16 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 16 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 16 0 4.5 0.03 400 0.05 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 16 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 16 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 2 ROADS/MOD 1 1 1 27 0 4 ROOF TOPS/FLAT 1 1 1 27 0 5 DRIVEWAYS/FLAT 1 1 1 27 0 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 2 0 0 1 0 0 0 4 0 0 1 0 0 0 5 0 0 1 0 0 0 8 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 2 0 0 4 0 0 4 1 9 4 0 0 4 0 0 0 1 9 5 0 0 4 0 0 0 1 9 8 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 2 0 0 0 0 0 23531 WWHM 8/30/2024 10:05:09 AM Page 23 4 0 0 0 0 0 5 0 0 0 0 0 8 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 2 400 0.05 0.1 0.08 4 400 0.01 0.1 0.1 5 400 0.01 0.1 0.1 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 2 0 0 4 0 0 5 0 0 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 2 0 0 4 0 0 5 0 0 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 16 0.14 COPY 501 12 PERLND 16 0.14 COPY 501 13 IMPLND 2 0.06 COPY 501 15 IMPLND 4 0.1 COPY 501 15 IMPLND 5 0.03 COPY 501 15 IMPLND 8 0.03 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 23531 WWHM 8/30/2024 10:05:10 AM Page 24 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN 23531 WWHM 8/30/2024 10:05:10 AM Page 25 Predeveloped HSPF Message File 23531 WWHM 8/30/2024 10:05:10 AM Page 26 Mitigated HSPF Message File 23531 WWHM 8/30/2024 10:05:10 AM Page 27 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2024; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com