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Rpt (Storm) STC LD20220109 Civil Engineers ● Structural Engineers ● Landscape Architects ● Community Planners ● Land Surveyors Preliminary Stormwater Report PREPARED FOR: Purvis/Evans c/o Scott Kaul Tacoma, WA PROJECT: The Summit at Thompson Creek Yelm, WA 2220471.11 PREPARED BY: Michael C. Hager, PE Project Engineer REVIEWED BY: Scott T. Kaul, PE, LEED AP Associate Principal DATE: August 2022 Revised September 2024 Preliminary Stormwater Report PREPARED FOR: Purvis/Evans c/o Scott Kaul Tacoma, WA PROJECT: The Summit at Thompson Creek Yelm, WA 2220471.11 PREPARED BY: Michael C. Hager, PE Project Engineer REVIEWED BY: Scott T. Kaul, PE, LEED AP Associate Principal DATE: August 2022 Revised September 2024 I hereby state that this Preliminary Stormwater Report for The Summit at Thompson Creek has been prepared by me or under my supervision and meets the standard of care and expertise that is usual and customary in this community for professional engineers. I understand that City of Yelm does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities prepared by me. 09/30/2024 Preliminary Stormwater Report The Summit at Thompson Creek 2220471.11 Table of Contents Section Page 1.0 Project Overview ............................................................................................................................ 1 2.0 Summary of Minimum Requirements .......................................................................................... 1 2.1 MR 1 – Preparation of Stormwater Site Plans .................................................................... 1 2.2 MR 2 - Construction Stormwater Pollution Prevention ....................................................... 1 2.3 MR 3 – Source Control of Pollution ..................................................................................... 1 2.4 MR 4 – Preservation of Natural Drainage Systems and Outfalls ........................................ 1 2.5 MR 5 – Onsite Stormwater Control ..................................................................................... 2 2.6 MR 6 – Runoff Treatment ................................................................................................... 2 2.7 MR 7 – Flow Control ........................................................................................................... 2 2.8 MR 8 – Wetlands Protection ............................................................................................... 2 2.9 MR 9 – Basin/Watershed Planning ..................................................................................... 2 2.10 MR 10 – Operation and Maintenance ................................................................................. 2 3.0 Existing Conditions ....................................................................................................................... 3 4.0 Soils Reports .................................................................................................................................. 3 5.0 Wells ................................................................................................................................................ 4 6.0 Fuel Tanks ...................................................................................................................................... 4 7.0 Sub-Basin Description................................................................................................................... 4 8.0 Analysis of the 100-Year Flood ..................................................................................................... 4 9.0 Aesthetic Considerations for Facilities ....................................................................................... 4 10.0 Facility Sizing and Downstream Analysis ................................................................................... 5 10.1 Conveyance ........................................................................................................................ 7 10.2 Treatment ............................................................................................................................ 8 10.3 Flow Control ........................................................................................................................ 8 10.4 Roof Runoff ......................................................................................................................... 8 10.5 Downstream Drainage ........................................................................................................ 9 11.0 Covenants Dedications, Easements ............................................................................................ 9 12.0 Property Owners Association Articles of Incorporation ............................................................ 9 13.0 Conclusion ...................................................................................................................................... 9 Preliminary Stormwater Report The Summit at Thompson Creek 2220471.11 Appendices Appendix A Exhibits A-1 ............. Vicinity Map A-2 ............. Existing Conditions Map A-3 ............. Developed Conditions Map A-4 ............. FEMA Flood Map A-5 ............. NRCS Soil Map A-6 ............. Downstream Drainage Map Appendix B Facility Sizing B-1 ............. Existing Basin Map B-2 ............. Developed Basin Map B-3 ............. WWHM Report (West Basin) B-4 ............. WWHM Report (East Basin) B-5 ............. WWHM Report (South Basin) B-6 ............. Roof Conveyance Flow Calculations Rational Appendix C Geotechnical Engineering Report South Sound Geotechnical Consulting, Inc. June 16, 2022 Geotechnical Seasonal Groundwater Monitoring (Winter 2022-2023) South Sound Geotechnical Consulting, Inc. May 12, 2023 Preliminary Stormwater Report The Summit at Thompson Creek 1 2220471.11 1.0 Project Overview This Preliminary Stormwater Report summarizes the storm drainage analysis and design for a 109-lot residential development located at 14444 Berry Valley Road SE, in Yelm, Washington. The land is currently partially developed with a single-family residence and additional associated structures. The southern portion of the project site was historically used for dairy farming. The project includes dividing the parcels into 109 residential lots for single-family homes and eight tracts. Construction will include new roadways and sidewalks, sewer, water services, and stormwater facilities to treat and discharge/dispose of the project's stormwater. The proposed roadway features and utilities will be extended from both Berry Valley Road SE and Jackson Street SE. Where feasible, the individual homes will also have onsite infiltration trenches and/or drywells to infiltrate roof runoff. The project involves three Thurston County tax parcel numbers (21724230100, 21723140000, and 21723140102). A proposed boundary line adjustment (BLA) will be recorded to transfer land area from Parcels 21723140102 and 21724230100 to Parcel 21723140000, with the remaining portion of Parcels 21723104102 and 21724230100 being removed from the overall project, resulting in a total project area of 28.86 acres located in Section 24, Township 17 North, Range 1 East, W.M. The increased stormwater runoff resulting from the addition of impervious area will be treated and retained/detained in accordance with the most recent Washington State Department of Ecology (DOE) Stormwater Management Manual for Western Washington (SWMMWW). 2.0 Summary of Minimum Requirements This project is subject to the SWMMWW and is a new development that will add more than 10,000 square feet of impervious surfaces; therefore, all Minimum Requirements (MRs) apply to this project. 2.1 MR 1 – Preparation of Stormwater Site Plans This preliminary report and the concept project plans represent the Preliminary Stormwater Site Plan for this project and satisfy MR 1. 2.2 MR 2 - Construction Stormwater Pollution Prevention A Construction Stormwater Pollution Prevention Plan (CSWPPP) will be prepared, under separate cover, for the site development permit application. 2.3 MR 3 – Source Control of Pollution Pollution source control Best Management Practices (BMPs) for a residential type project will be implemented, including BMPs such as street sweeping and landscape management. A CSWPPP will provide details on the control of pollution during construction. 2.4 MR 4 – Preservation of Natural Drainage Systems and Outfalls The project includes three primary discharge locations . The eastern portion of the site drains toward Thompson Creek and is characterized by soils conducive the infiltration. The project proposes to infiltrate all stormwater runoff generated within the East Basin. Runoff generated on the western and southern portions of the site enters a wetland complex along the western boundary, where the runoff continues northerly through a broad drainage channel. The locations of the two proposed wetpond/detention pond facilities have been designed to mimic and preserve the existing flow patterns from the project site. Preliminary Stormwater Report The Summit at Thompson Creek 2 2220471.11 2.5 MR 5 – Onsite Stormwater Control Where feasible, primarily in the eastern basin, individual roof runoff infiltration systems will be provided. Along the western perimeter of the site, roof runoff will be dispersed toward the wetland buffer areas to maintain flows along the length of the wetland. Post construction soil quality and depth BMPs will be implemented to enhance retention of precipitation across the site. 2.6 MR 6 – Runoff Treatment Over 5,000 square feet of pollution generating impervious surface (PGIS) will be added as part of these improvements; therefore, runoff treatment is required for this site. Stormwater runoff from pollution generating surfaces in the eastern basin will be conveyed to a proprietary water quality filter treatment structure before draining into an infiltration pond for treatment and disposal through infiltration. The water quality filter device is sized to treat the offline water quality flowrate, as calculated using the Western Washington Hydrology Model (WWHM 2012) meeting the SWMMWW treatment requirement. Wetponds will be used for treatment in the West and South basins. The wetponds consist of the lower stages of the combined wetpond/detention pond system with the minimum volume provided being based on the 24-hour runoff volume predicted by the WWHM model. Each wetpond will have two holding cells with internal berm 1-foot submerged per the SWMMWW standards. Refer to Section 10.0 for facility sizing. 2.7 MR 7 – Flow Control The project exceeds the thresholds for new development projects and must provide flow control . Proposed flow control is achieved in the East Basin with the use of an infiltration pond that will infiltrate 100 percent of developed stormwater runoff. Flow control is provided in the West and South basins through the use of the combination wetpond/detention ponds. The pond detention volumes and discharge control structures are designed to match the discharge durations of the predeveloped site , assuming forested conditions from 50 percent of the 2-year peak flow to the full 50-year peak flow. Refer to Section 10.0 for facility sizing. 2.8 MR 8 – Wetlands Protection A wetland delineation and stream assessment was performed by Land Services Northwest, which identified three wetlands and a Type F stream on or adjacent to the project site. The identified wetlands, stream, and associated buffers will be preserved by protected tracts within the development. Runoff from portions of the project site will be dispersed toward the wetland buffer areas to preserve the existing flow patterns. The runoff from the southern wetpond/detention pond will be discharged to the larger onsite wetland, matching the existing runoff discharge location. 2.9 MR 9 – Basin/Watershed Planning To our knowledge, there are no existing basin plans. 2.10 MR 10 – Operation and Maintenance The stormwater system for the roadway improvements will be publicly owned and maintained. City of Yelm shall be responsible for the operation and maintenance of the public stormwater facilities. Preliminary Stormwater Report The Summit at Thompson Creek 3 2220471.11 Operation and maintenance for drainage facilities constructed for each lot shall be the responsibility of the individual owners. 3.0 Existing Conditions The development portion of the site contains moderate to steep slopes with a ridge line running south to north. Runoff from the eastern portion of the site flows easterly toward Thompson Creek, while the portion to the west of the ridge flows to the wetlands located at the western site boundary. The northwestern portion of the site is densely forested with mature trees and underbrush. The eastern portion of the site consists of grass with sparse trees and includes physical improvements associated with the existing residence, including gravel driveways and outbuildings. The southern portion of the project site is primarily grass -covered with a few sporadic trees and shrubs, with greater vegetation density along the southern boundary. 4.0 Soils Reports The soils identified by the Natural Resources Conservation Service (NRCS) Web Soil Survey (Appendix A-5) vary across the project site. The soils on the lower eastern portion of the site associated with Thompson Creek are identified as Nisqually loamy fine sand, 3 to 15 percent slopes (74). The soils mid-slope within the East Basin are Spanaway gravelly sandy loam, 3 to 15 percent slopes (111). This portion of the project site is conducive the infiltration. Lots within the Spanaway soil area will be provided within individual roof drain infiltration systems . The largest soil area in the central, higher elevation portion of the site is identified as McChord- Everett complex, 3 to 15 percent slopes. This soil is classified as hydrologic soil group Type A; however, soil test holes dug by South Sound Geotechnical Consulting determined that the surface soils were underlain by glacial till/drift located approximately 1 to 5 feet below ground surface. Therefore, for stormwater modelling purposes, this soil is assumed to function as Type C. The soils located on the western perimeter of the site associated with the wetland areas are identified as Steilacoom-Yelm complex, 0 to 2 percent slopes (100) and Mckenna gravelly silt loam, 0 to 5 percent slopes (65). Soil test holes dug across the proposed project site generally match the soil types identified by the NRCS soil survey. Infiltration testing was performed in the location of the proposed eastern bioinfiltration/infiltration facility, with an observed infiltration rate of 62 in/hr. A corrected infiltration rate of 28 in/hr is recommended by the Geotechnical Engineer. However, considering the potential presence of shallow groundwater, a conservative design rate of 4 in/hr was used for preliminary stormwater calculations. Please refer to Appendix C for the complete South Sound Geotechnical Consulting report. Preliminary Stormwater Report The Summit at Thompson Creek 4 2220471.11 5.0 Wells There are two private wells located on the associated project properties. One well is located on the portion of Parcel 21723140102 that will be removed by BLA from the project. This well will remain in service with all proposed development being set back a minimum of 100 feet. The second existing well is located on Parcel 2172314000 and will be abandoned prior to final plat. Each lot will be served by the City of Yelm STEP collection system. The holding tank will be maintained by the City and pumped on a regular basis. Domestic water will be provided by the City of Yelm water distribution system. 6.0 Fuel Tanks No fuel tanks were observed at the project site. 7.0 Sub-Basin Description Review of available GIS topographic information indicates that the developed portion of the project site will receive runoff from the adjacent area of Parcel 21723140102. This area is accounted for in the pre-developed and developed basin areas used in sizing the proposed stormwater management facilities. The runoff from the project’s eastern basin area will be infiltrated onsite. Discharge from the western detention facility flows northerly through a broad drainage channel. Discharge from the southern pond enters the wetland complex, where it eventually exits the project site at the northern boundary near Pond #1 and continues to flow north, matching existing conditions. Existing areas to the south and southeast of the basins will run onto the basins and are included in stormwater models with existing land coverage types. To our knowledge, no critical infrastructure is located immediately downstream from the project site and potential anticipated impacts to the downstream basin area are mitigated by the proposed stormwater management facilities. 8.0 Analysis of the 100-Year Flood Federal Emergency Management Agency (FEMA) mapping indicates a Zone A associated with Thompson Creek. Base flood elevations have not been established, but observation indicates that the flood elevation should not exceed elevation 326. The lowest proposed lot pad elevation is 335.25. Refer to Appendix A-4 for the FEMA Flood Map. 9.0 Aesthetic Considerations for Facilities The proposed infiltration facility is located within a proposed stormwater tract. The facility is designed with a maximum storage depth of 3 feet and side slopes will not exceed 3:1. This facility will be unobtrusive due to the shallow nature and moderate side slopes. The two wetpond/detention ponds are located within natural low areas and will be provided with 3:1 slopes and within proposed stormwater tracts. Fencing and landscape screening may be implemented to minimize the visual impact of these facil ities. Preliminary Stormwater Report The Summit at Thompson Creek 5 2220471.11 10.0 Facility Sizing and Downstream Analysis The project site is modeled as three separate basins for stormwater facility sizing (East, West, and South). Impervious surfaces associated with proposed roads, sidewalks, and driveway approaches were calculated based on the site plan layout. An additional 500 square feet of impervious surfaces per lot were assumed for driveways (2,500 square feet for flag lots). Assumed roof area is based on each lot’s building envelope and varies from 1,500 square feet to a maximum of 2,500 square feet, with the average being 2,200 square feet. In the Eastern Basin, eight of the lower lots, located in an area of infiltratable soils, will have infiltration trenches to infiltrate their roof runoff; this area is removed from the basin area tributary to the proposed bioretention/infiltration facility. The other 18 lots, located in uninfiltratable soils or located with tall site walls preventing infiltration trenches , will have roof runoffs draining to the infiltration trench. In the Southern and Western Basins, a number of lots located near the existing wetlands will have dispersal trenches, while the other roof in these basins will have private runoff collection systems that will drain to the wetpond/detention ponds. Each basin also includes bypass areas where , due to topographic constraints, the runoff is not directed to the stormwater facility. The bypass areas consist of non-pollution generating surfaces and the area is included in the downstream drainage compliance calculations. The stormwater system was sized and analyzed using WWHM. The following tables summarize the existing and developed areas within each basin area. East Basin Existing Areas Area (sf) Area (ac) Total Basin Area 392,773 9.017 Forest (moderate onsite) 183,021 4.202 Forest (steep onsite) 37,164 0.853 Forest (moderate offsite) 81,172 1.863 Forest (steep offsite) 14,987 0.344 Lawn (moderate offsite) 76,429 1.755 Developed Areas (to Infiltration) Area (sf) Area (ac) Total Basin Area 389,407 8.940 Roof Area Infiltrated on Lots 8,375 0.192 Total Area to Facility (total - roof) 381,032 8.747 Pavement 28,488 0.654 Sidewalk and Approaches 9,845 0.226 Driveway 13,000 0.298 Roof 48,308 1.109 Lawn/Landscape* 81,555 2.498 Forest (moderate offsite) 81,172 1.863 Forest (steep offsite) 14,987 0.344 Lawn (moderate offsite) 76,429 1.755 *Proposed landscape areas are modeled as pasture due to implementation of post-construction soil quality and depth BMPs. Preliminary Stormwater Report The Summit at Thompson Creek 6 2220471.11 West Basin Existing Areas Area (sf) Area (ac) Total Basin Area 284,228 6.525 Forest (moderate onsite) 247,999 5.693 Forest (steep onsite) 36,229 0.832 Developed Areas (to Pond #1) Area (sf) Area (ac) Total Basin Area 333,365 7.653 Pavement 56,759 1.303 Sidewalk & Approaches 16,553 0.380 Driveway 25,483 0.585 Roof 81,980 1.882 Lawn/Landscape* 152,591 3.503 Developed Areas (Bypass) Area (sf) Area (ac) Total Basin Area 36,500 0.838 Roof** 7,500 0.172 Lawn/Landscape* 29,000 0.666 *Proposed landscape areas are modeled as pasture due to implementation of post -construction soil quality and depth BMPs. **Bypass roof areas in the West and South Basins are modeled as grass to reflect the proposed dispersion BMPs. South Basin Existing Areas Area (sf) Area (ac) Total Basin Area 543,740 12.483 Forest (moderate onsite) 416,230 9.555 Forest (moderate offsite) 20,875 0.479 Lawn (moderate offsite) 106,678 2.449 Developed Areas (to Pond #2) Area (sf) Area (ac) Total Basin Area 390,560 8.966 Pavement 42,080 0.966 Sidewalk and Approaches 5,490 0.126 Driveway 18,100 0.416 Roof 66,300 1.522 Lawn/Landscape* 131,072 3.009 Forest (moderate offsite) 20,875 0.479 Lawn (moderate offsite) 106,635 2.448 Developed Areas (Bypass) Area (sf) Area (ac) Total Basin Area 50,140 1.151 Roof** 50,140 1.151 *Proposed landscape areas are modeled as pasture due to implementation of post-construction soil quality and depth BMPs. **Bypass roof areas in the West and South Basins are modeled as grass to reflect the proposed dispersion BMPs. Preliminary Stormwater Report The Summit at Thompson Creek 7 2220471.11 10.1 Conveyance The proposed conveyance system consists of a series of new catch basins, pipe reaches, and outfalls to the proposed stormwater management facilities. The conveyance system will be designed to convey a minimum of the 25-year, 24-hour design runoff event. Refer to the table below for critical pipes and flow rates based on Manning’s Flow Calculations for partially full pipes with a roughness coefficient n=0.010 for CPEP piping. The 25-year and 100-year events are shown to be well under the full-flow capacity of the lowest capacity pipe in the system. Pipe Location 25-Year Flowrate 100-Year Flowrate Lowest Capacity Pipe Geometry Full Flow Capacity South Basin Prior Pond 4.12 cfs inflow 5.69 cfs inflow 12” CPEP @ 0.5% 2.53 cfs South Basin Pond Outlet 1.16 cfs mit. 1.69 cfs mit. 18” CPEP @ 0.2% 6.11 cfs West Basin Prior Pond 4.26 cfs inflow 5.64 cfs inflow 12” CPEP @ 0.5% 2.53 cfs West Basin Pond Outlet 0.45 cfs mit. 0.64 cfs mit. 18” CPEP @ 0.5% 9.66 cfs East Basin Prior Pond 2.37 cfs inflow 3.20 cfs inflow 12” CPEP @ 0.5% 2.53 cfs East Basin Pond Outlet NA NA NA NA Roof areas draining to the ponds will be conveyed in private conveyance networks, located in 2-foot wide stormwater easements behind the 10-foot wide joint utility easements at the front of the lots. These will consist of 6-inch PVC and 8-inch PVC networks designed to convey a minimum of the 25-year, 24-hour design runoff events. Refer to the tables below for critical pipes and flow rates based on Manning’s Flow Calculations for partially full pipes with a roughness coefficient n=0.010 for PVC piping. Pipe Location 25-Year Flowrate 100-Year Flowrate Lots 17-24 (8 lots) 0.906cfs 1.134cfs Lots 4-12 (9 lots) 1.072cfs 1.342cfs Lots 25-31 (7 lots) 1.035cfs 1.296cfs Lots 66-72 (7 lots) 0.961cfs 1.203cfs Lowest Capacity Pipe Geometry Full Flow Capacity 6” PVC @ 0.5% 0.52 cfs 6” PVC @ 1.0% 0.73 cfs 6” PVC @ 1.5% 0.90 cfs 6” PVC @ 2.0% 1.04 cfs 6” PVC @ 3.0% 1.26 cfs 6” PVC @ 5.0% 1.63 cfs 8” PVC @ 0.5% 1.11 cfs 8” PVC @ 1.0% 1.57 cfs Preliminary Stormwater Report The Summit at Thompson Creek 8 2220471.11 10.2 Treatment East Basin Runoff quality control for the East Basin is provided by a proprietary water quality filter treatment structure before draining into an infiltration pond for full infiltration. The water quality filter device is sized to treat the offline water quality flowrate, as calculated using WWHM 2012, meeting the SWMMWW treatment requirement. Offline flowrates were chosen due to the internal weir wall that will allow higher flows to bypass the filters. Refer to the WWHM model in Appendix B for the water quality flowrates. West Basin Quality control for runoff from the West Basin is provided by a proposed wetpond . The wetpond volume will be provided in the lower stages of the combined wetpond/detention Pond #1 . The pond will be divided into two cells with 3:1 side slopes. The wetpond storage volume matches the 24-hour water quality volume calculated by WWHM. Refer to the WWHM model in Appendix B for the water quality flowrates. South Basin Quality control for runoff from the South Basin is provided by a proposed wetpond. The wetpond volume will be provided in the lower stages of the combined wetpond/detention Pond #2 . The pond will be divided into two cells with 3:1 side slopes. The wetpond storage volume matches the 24-hour water quality volume calculated by WWHM. Refer to the WWHM model in Appendix B for the water quality flowrates. 10.3 Flow Control East Basin Stormwater runoff enters the infiltration portion of the stormwater facility after draining through the water quality filter structure and roof drain conveyance network. The infiltration pond provides a 4,005-square foot, unlined, infiltration surface, with a design infiltration rate of 4 in/hr. WWHM results show that the infiltration pond can infiltrate 100 percent of the tributary runoff with a maximum storage depth of 3.0 feet. Refer to the WWHM model in Appendix B. West and South Basins Detention volume is provided above the wetpond stage to temporarily store and discharge runoff from the site at a controlled rate. A combination orifice and notched weir control structure regulates the discharge from each pond, matching the pre-developed condition flow durations. A summary of the duration analysis for the West and South Detention Ponds is provided in the WWHM reports included in Appendix B. 10.4 Roof Runoff Roof runoff in managed by the proposed stormwater facilities, dispersal into buffer areas, or infiltrated onsite where soils allow. Where feasible, stormwater runoff from the roof area of the homes will be infiltrated in individual drywells. The drywells will be sized in accordance with SWMMWW Volume 3, Chapter 3, Section 3.1.1 - BMP T5.10A Downspout Full Infiltration System. Preliminary Stormwater Report The Summit at Thompson Creek 9 2220471.11 10.5 Downstream Drainage Runoff within the East Basin is proposed to be fully infiltrated with a small area of bypass . The runoff from the project site is not anticipated to have adverse effects on Thompson Creek. Runoff discharged from Ponds #1 and #2 will exit the project site at the northeast corner. The discharge from Pond #1 will be through a proposed level-spreader device. The runoff will continue in a northerly direction through a broad-flat drainage channel through mostly undeveloped land to an intersection point with 93rd Avenue East over 0.25 mile downstream from the project site. The pond discharge durations will match pre-developed conditions, therefore, impact to the downstream flow path is not anticipated. 11.0 Covenants Dedications, Easements Public right-of-way will be created by this proposal. In addition to the right-of-way, 10-foot wide joint utility (JUT) easements, with 2-foot wide private storm conveyance easements behind the JUT easement, will be provided on each side of the proposed road . Ingress/egress easements will be granted to the property to the south and west. 12.0 Property Owners Association Articles of Incorporation Not applicable. 13.0 Conclusion The proposed project involves site improvements associated with a 109-lot development. The project includes clearing, grading, erosion control, utility improvements, and stormwater management facilities. The site, as proposed, will meet the requirements of the most recent Department of Ecology Stormwater Management Manual for Western Washington (SWMMWW). This report and associated plans have been prepared within the guidelines established by City of Yelm for stormwater management. This analysis is based on data and records either supplied to or obtained by AHBL. These documents are referenced within the text of the analysis. The analysis has been prepared using procedures and practices within the standard accepted practices of the industry. AHBL, Inc. Michael C. Hager, PE Project Engineer MCH/lsk August 2022 Revised September 2024 Q:\2022\2220471\WORDPROC\Reports\20240930 Rpt (Storm) 2220471.11.docx Preliminary Stormwater Report The Summit at Thompson Creek 2220471.11 Appendix A Exhibits A-1 .................... Vicinity Map A-2 .................... Existing Conditions Map A-3 .................... Developed Conditions Map A-4 .................... FEMA Flood Map A-5 .................... NRCS Soil Map A-6 .................... Downstream Drainage Map 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX THE SUMMIT AT THOMPSON CREEK 2210919.10 VICINITY MAP A-1 N VICINITY MAP NOT TO SCALE SITE N GRAPHIC SCALE 0 80 160 FEET 1" = 80 FEET 40 BERRY VAL L E Y R O A D S E 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX JOB NO. DATE: THE SUMMIT AT THOMPSON CREEK EXISTING CONDITIONS MAP A-2 2210919.10 JULY 2022 929394 84 696168606766 58 65 TRACT 'E' 6463 7062 2 TRACT 'G' 42 41 46 47 TR A C T ' D ' 71 TR A C T ' C ' 83 72 80 TRACT 'B' 82 81 TRACT 'J' TRACT 'A' 79 76 77 78 74 75 73 24 1 21 22 108 106 105 53 54 56 57 28 31 25 TRACT 'I' 51 50 49 59 91 89 88 87 85 97 18 23 8690 38 TRACT 'L' 104107 109 43 48 55 45 TRACT 'H' 44 TRACT 'K' 52 3 102 100 99 9596 103 98 101 36 37 35 14 6 13 5 12 4 11 10 9 16 8 15 7 17 31 36 37 39 40 35 34 33 32 30 14 20 13 19 12 11 10 9 8 15 7 29 27 26 13 12 11 10 9 8 7 17 31 27 26 28 31 21 18 38 36 37 39 40 35 34 33 32 30 14 6 20 13 5 19 12 4 11 10 9 16 8 15 7 17 29 27 26 17 6 9 18 38 11 350 34 8 35 2 35 4 35 6 358 35 8 3 5 6 3 5 4 3 5 2 35 0 34 8 34 6 344 342 340 334 336 338 332 3 6 4 3 6 2 360 358 356 354 352 36 6 364 362 360 3 5 8 3 5 6 3 5 8 368 3 3 0 3 3 2 34 0 352354356 356358 364366 340 346 346 334 334 3 4 0 3 4 6 3 4 6 3343 3 4 36035635836 2 35 2 35 4 3 5 6 3 5 4 37 0 36 2 36 4 36 6 36 8 38 2 380 382 378 382 376 36 8 37 6 3 7 6 356 3 7 4 370 330 370 380 36 4 366 368 372 374 376 378 38 2 3 6 6 3 6 8 35 2 35 4 N GRAPHIC SCALE 0 80 160 FEET 1" = 80 FEET 40 BERRY VAL L E Y R O A D S E 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX JOB NO. DATE: THE SUMMIT AT THOMPSON CREEK DEVELOPED CONDITIONS MAP A-3 2220471.10 9/30/2024 National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 7/29/2022 at 1:16 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 122°38'14"W 46°57'4"N 122°37'37"W 46°56'39"N Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020 A-4 Soil Map—Thurston County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/19/2022 Page 1 of 3 51 9 9 1 0 0 51 9 9 2 0 0 51 9 9 3 0 0 51 9 9 4 0 0 51 9 9 5 0 0 51 9 9 6 0 0 51 9 9 1 0 0 51 9 9 2 0 0 51 9 9 3 0 0 51 9 9 4 0 0 51 9 9 5 0 0 51 9 9 6 0 0 527400 527500 527600 527700 527800 527900 528000 528100 528200 528300 528400 527400 527500 527600 527700 527800 527900 528000 528100 528200 528300 528400 46° 56' 59'' N 12 2 ° 3 8 ' 2 7 ' ' W 46° 56' 59'' N 12 2 ° 3 7 ' 3 5 ' ' W 46° 56' 40'' N 12 2 ° 3 8 ' 2 7 ' ' W 46° 56' 40'' N 12 2 ° 3 7 ' 3 5 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 100 200 400 600 Feet 0 40 80 160 240 Meters Map Scale: 1:2,920 if printed on B landscape (17" x 11") sheet. Soil Map may not be valid at this scale. A-5 350 34 8 35 2 35 4 35 6 358 35 8 3 5 6 3 5 4 3 5 2 35 0 34 8 346 344 342 340 338 336 334 3 6 2 360 358 356 354 352 36 6 364 362 360 3 5 8 354 3 5 6 3 5 8 364 366 3 3 0 3 3 2 3 3 2 3 3 8 35 2 34 2 342348360 354 354 348366 346 33 6 34 4 35 8 3 6 2 340 346 346 336 336 3 4 0 3 4 6 3 4 6 334 334338 340 356360 362 356 35 4 35 2 350 360 352 344 356 350 N 0 100 200 FEET 1" = 100 FEET GRAPHIC SCALE 500 93RD AVE SE 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX JOB NO. DATE: THE SUMMIT AT THOMPSON CREEK DOWNSTREAM DRAINAGE MAP A-6 2210919.10 JULY 2022 DOWNSTREAM FLOW PATH 1630± FEET DOWNSTREAM FROM PROJECT SITE THOMPSON CREEK Preliminary Stormwater Report The Summit at Thompson Creek 2220471.11 Appendix B Facility Sizing B-1 .................... Existing Basin Map B-2 .................... Developed Basin Map B-3 .................... WWHM Report (West Basin) B-4 .................... WWHM Report (East Basin) B-5 .................... WWHM Report (South Basin) B-6 .................... Roof Conveyance Flow Calculations Rational N GRAPHIC SCALE 0 80 160 FEET 1" = 80 FEET 40 BERRY VAL L E Y R O A D S E 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX JOB NO. DATE: THE SUMMIT AT THOMPSON CREEK EXISTING BASIN MAP B-1 2210919.10 JULY 2022 EAST BASIN WEST BASIN SOUTH BASIN 13 12 11 10 9 8 7 31 28 31 18 38 6 9 18 38 11 350 34 8 35 2 35 4 35 6 358 35 8 3 5 6 3 5 4 3 5 2 35 0 34 8 34 6 344 342 340 334 336 338 332 3 6 4 3 6 2 360 358 356 354 352 36 6 364 362 360 3 5 8 3 5 6 3 5 8 368 3 3 0 3 3 2 34 0 352354356 356358 364366 340 346 346 334 334 3 4 0 3 4 6 3 4 6 3343 3 4 36035635836 2 35 2 35 4 3 5 6 3 5 4 37 0 36 2 36 4 36 6 36 8 38 2 380 382 378 382 376 36 8 37 6 3 7 6 356 3 7 4 370 330 370 380 36 4 366 368 372 374 376 378 38 2 3 6 6 3 6 8 35 2 35 4 N GRAPHIC SCALE 0 80 160 FEET 1" = 80 FEET 40 BERRY VAL L E Y R O A D S E INFILTRATION POND EAST 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX JOB NO. DATE: THE SUMMIT AT THOMPSON CREEK DEVELOPED BASIN MAP B-2 2220471.10 9/30/2024 WETPOND/DETENTION POND WEST WETPOND/DETENTION POND SOUTH WEST BASIN BYPASS SOUTH BASIN BYPASS EAST BASIN WEST BASIN SOUTH BASIN BIO-INFILTRATION/ INFILTRATION POND #2 OFFSITE (BERRY VALLEY) BASIN LOTS INFILTRATING ROOF DRAINAGE WWHM2012 PROJECT REPORT Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 2 General Model Information Project Name:Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm Site Name:Summit at Thompson Site Address:Berry Valley City:Yelm Report Date:8/23/2024 Gage:Eaton Creek Data Start:1955/10/01 Data End:2011/09/30 Timestep:15 Minute Precip Scale:0.000 (adjusted) Version Date:2021/08/18 Version:4.2.18 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Low Flow Threshold for POC2:50 Percent of the 2 Year High Flow Threshold for POC2:50 Year Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 3 Landuse Basin Data Predeveloped Land Use EX WESTBASIN Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Mod 5.693 C, Forest, Steep 0.832 Pervious Total 6.525 Impervious Land Use acre Impervious Total 0 Basin Total 6.525 Element Flows To: Surface Interflow Groundwater Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 4 Mitigated Land Use Dev West Pond Bypass:No GroundWater:No Pervious Land Use acre C, Pasture, Flat 3.503 Pervious Total 3.503 Impervious Land Use acre ROADS MOD 1.303 ROOF TOPS FLAT 1.882 DRIVEWAYS MOD 0.585 SIDEWALKS MOD 0.38 Impervious Total 4.15 Basin Total 7.653 Element Flows To: Surface Interflow Groundwater Trapezoidal Pond 1 Trapezoidal Pond 1 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 5 West Bypass Bypass:Yes GroundWater:No Pervious Land Use acre C, Lawn, Mod 0.172 C, Pasture, Flat 0.666 Pervious Total 0.838 Impervious Land Use acre Impervious Total 0 Basin Total 0.838 Element Flows To: Surface Interflow Groundwater Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 6 Routing Elements Predeveloped Routing Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 7 Mitigated Routing Trapezoidal Pond 1 Bottom Length:113.05 ft. Bottom Width:113.05 ft. Depth:8 ft. Volume at riser head:2.9233 acre-feet. Side slope 1:3 To 1 Side slope 2:3 To 1 Side slope 3:3 To 1 Side slope 4:3 To 1 Discharge Structure Riser Height:7 ft. Riser Diameter:12 in. Notch Type:Rectangular Notch Width:0.668 ft. Notch Height:0.339 ft. Orifice 1 Diameter:1.471 in.Elevation:0 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.293 0.000 0.000 0.000 0.0889 0.296 0.026 0.017 0.000 0.1778 0.298 0.052 0.024 0.000 0.2667 0.301 0.079 0.030 0.000 0.3556 0.304 0.106 0.035 0.000 0.4444 0.307 0.133 0.039 0.000 0.5333 0.310 0.160 0.042 0.000 0.6222 0.313 0.188 0.046 0.000 0.7111 0.315 0.216 0.049 0.000 0.8000 0.318 0.244 0.052 0.000 0.8889 0.321 0.273 0.055 0.000 0.9778 0.324 0.302 0.058 0.000 1.0667 0.327 0.331 0.060 0.000 1.1556 0.330 0.360 0.063 0.000 1.2444 0.333 0.389 0.065 0.000 1.3333 0.336 0.419 0.067 0.000 1.4222 0.339 0.449 0.070 0.000 1.5111 0.342 0.479 0.072 0.000 1.6000 0.345 0.510 0.074 0.000 1.6889 0.348 0.541 0.076 0.000 1.7778 0.351 0.572 0.078 0.000 1.8667 0.354 0.603 0.080 0.000 1.9556 0.357 0.635 0.082 0.000 2.0444 0.360 0.667 0.084 0.000 2.1333 0.363 0.699 0.085 0.000 2.2222 0.366 0.731 0.087 0.000 2.3111 0.369 0.764 0.089 0.000 2.4000 0.372 0.797 0.091 0.000 2.4889 0.376 0.830 0.092 0.000 2.5778 0.379 0.864 0.094 0.000 2.6667 0.382 0.898 0.095 0.000 2.7556 0.385 0.932 0.097 0.000 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 8 2.8444 0.388 0.966 0.099 0.000 2.9333 0.391 1.001 0.100 0.000 3.0222 0.395 1.036 0.102 0.000 3.1111 0.398 1.071 0.103 0.000 3.2000 0.401 1.107 0.105 0.000 3.2889 0.404 1.143 0.106 0.000 3.3778 0.408 1.179 0.107 0.000 3.4667 0.411 1.215 0.109 0.000 3.5556 0.414 1.252 0.110 0.000 3.6444 0.417 1.289 0.112 0.000 3.7333 0.421 1.326 0.113 0.000 3.8222 0.424 1.364 0.114 0.000 3.9111 0.427 1.402 0.116 0.000 4.0000 0.431 1.440 0.117 0.000 4.0889 0.434 1.478 0.118 0.000 4.1778 0.437 1.517 0.120 0.000 4.2667 0.441 1.556 0.121 0.000 4.3556 0.444 1.596 0.122 0.000 4.4444 0.448 1.635 0.123 0.000 4.5333 0.451 1.675 0.125 0.000 4.6222 0.455 1.715 0.126 0.000 4.7111 0.458 1.756 0.127 0.000 4.8000 0.461 1.797 0.128 0.000 4.8889 0.465 1.838 0.129 0.000 4.9778 0.468 1.880 0.131 0.000 5.0667 0.472 1.922 0.132 0.000 5.1556 0.475 1.964 0.133 0.000 5.2444 0.479 2.006 0.134 0.000 5.3333 0.483 2.049 0.135 0.000 5.4222 0.486 2.092 0.136 0.000 5.5111 0.490 2.135 0.137 0.000 5.6000 0.493 2.179 0.139 0.000 5.6889 0.497 2.223 0.140 0.000 5.7778 0.500 2.268 0.141 0.000 5.8667 0.504 2.312 0.142 0.000 5.9556 0.508 2.357 0.143 0.000 6.0444 0.511 2.403 0.144 0.000 6.1333 0.515 2.448 0.145 0.000 6.2222 0.519 2.494 0.146 0.000 6.3111 0.522 2.540 0.147 0.000 6.4000 0.526 2.587 0.148 0.000 6.4889 0.530 2.634 0.149 0.000 6.5778 0.534 2.681 0.150 0.000 6.6667 0.537 2.729 0.152 0.000 6.7556 0.541 2.777 0.217 0.000 6.8444 0.545 2.825 0.328 0.000 6.9333 0.549 2.874 0.470 0.000 7.0222 0.552 2.923 0.629 0.000 7.1111 0.556 2.972 0.985 0.000 7.2000 0.560 3.022 1.504 0.000 7.2889 0.564 3.072 2.045 0.000 7.3778 0.568 3.122 2.477 0.000 7.4667 0.572 3.173 2.737 0.000 7.5556 0.575 3.224 2.947 0.000 7.6444 0.579 3.275 3.129 0.000 7.7333 0.583 3.327 3.299 0.000 7.8222 0.587 3.379 3.459 0.000 7.9111 0.591 3.431 3.610 0.000 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 9 8.0000 0.595 3.484 3.754 0.000 8.0889 0.599 3.537 3.892 0.000 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:22:08 AM Page 10 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:6.525 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:4.341 Total Impervious Area:4.15 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.299159 5 year 0.501527 10 year 0.675925 25 year 0.949976 50 year 1.198315 100 year 1.489188 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.178869 5 year 0.256944 10 year 0.319244 25 year 0.411307 50 year 0.49045 100 year 0.57942 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1956 0.338 0.188 1957 0.613 0.247 1958 0.276 0.127 1959 0.278 0.175 1960 0.384 0.352 1961 0.297 0.166 1962 0.111 0.115 1963 0.738 0.304 1964 0.293 0.173 1965 0.314 0.163 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:03 AM Page 11 1966 0.170 0.133 1967 0.403 0.166 1968 0.244 0.131 1969 0.152 0.127 1970 0.262 0.174 1971 0.336 0.186 1972 0.780 0.678 1973 0.283 0.184 1974 0.224 0.162 1975 0.207 0.133 1976 0.387 0.208 1977 0.088 0.092 1978 0.325 0.184 1979 0.263 0.130 1980 0.284 0.167 1981 0.914 0.322 1982 0.240 0.210 1983 0.468 0.202 1984 0.386 0.147 1985 0.126 0.124 1986 0.500 0.200 1987 0.449 0.203 1988 0.206 0.148 1989 0.517 0.231 1990 0.411 0.193 1991 2.876 0.450 1992 0.575 0.202 1993 0.190 0.192 1994 0.155 0.109 1995 0.414 0.196 1996 0.650 0.621 1997 0.295 0.299 1998 0.520 0.234 1999 0.392 0.366 2000 0.250 0.151 2001 0.254 0.165 2002 0.145 0.115 2003 0.248 0.173 2004 0.414 0.204 2005 0.221 0.129 2006 0.304 0.157 2007 0.302 0.267 2008 0.260 0.160 2009 0.513 0.212 2010 0.129 0.127 2011 0.203 0.139 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 2.8759 0.6776 2 0.9137 0.6214 3 0.7800 0.4504 4 0.7379 0.3658 5 0.6499 0.3523 6 0.6132 0.3220 7 0.5747 0.3044 8 0.5200 0.2994 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:03 AM Page 12 9 0.5169 0.2667 10 0.5131 0.2473 11 0.4998 0.2340 12 0.4681 0.2306 13 0.4487 0.2116 14 0.4141 0.2098 15 0.4137 0.2081 16 0.4110 0.2043 17 0.4027 0.2033 18 0.3922 0.2024 19 0.3873 0.2022 20 0.3860 0.1997 21 0.3840 0.1955 22 0.3383 0.1926 23 0.3362 0.1925 24 0.3248 0.1876 25 0.3143 0.1857 26 0.3043 0.1845 27 0.3018 0.1841 28 0.2974 0.1746 29 0.2949 0.1742 30 0.2933 0.1734 31 0.2837 0.1729 32 0.2829 0.1672 33 0.2782 0.1657 34 0.2755 0.1656 35 0.2627 0.1646 36 0.2617 0.1631 37 0.2598 0.1616 38 0.2537 0.1598 39 0.2501 0.1566 40 0.2476 0.1514 41 0.2437 0.1476 42 0.2399 0.1473 43 0.2235 0.1389 44 0.2211 0.1335 45 0.2071 0.1331 46 0.2062 0.1307 47 0.2027 0.1297 48 0.1897 0.1289 49 0.1696 0.1269 50 0.1554 0.1268 51 0.1516 0.1266 52 0.1447 0.1243 53 0.1287 0.1148 54 0.1262 0.1147 55 0.1113 0.1093 56 0.0881 0.0918 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:03 AM Page 13 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.1496 16549 16537 99 Pass 0.1602 13871 9001 64 Pass 0.1708 11780 4538 38 Pass 0.1814 9936 2032 20 Pass 0.1920 8571 1280 14 Pass 0.2025 7275 858 11 Pass 0.2131 6195 691 11 Pass 0.2237 5365 609 11 Pass 0.2343 4636 546 11 Pass 0.2449 4006 486 12 Pass 0.2555 3424 441 12 Pass 0.2661 2945 387 13 Pass 0.2767 2551 354 13 Pass 0.2873 2172 319 14 Pass 0.2979 1888 274 14 Pass 0.3085 1629 231 14 Pass 0.3191 1387 202 14 Pass 0.3297 1232 180 14 Pass 0.3403 1052 150 14 Pass 0.3509 928 135 14 Pass 0.3614 794 113 14 Pass 0.3720 666 102 15 Pass 0.3826 582 98 16 Pass 0.3932 499 94 18 Pass 0.4038 422 90 21 Pass 0.4144 358 86 24 Pass 0.4250 321 83 25 Pass 0.4356 286 80 27 Pass 0.4462 246 75 30 Pass 0.4568 216 71 32 Pass 0.4674 179 68 37 Pass 0.4780 158 64 40 Pass 0.4886 138 60 43 Pass 0.4992 113 56 49 Pass 0.5098 96 53 55 Pass 0.5203 82 50 60 Pass 0.5309 72 47 65 Pass 0.5415 60 45 75 Pass 0.5521 55 41 74 Pass 0.5627 51 38 74 Pass 0.5733 47 35 74 Pass 0.5839 42 30 71 Pass 0.5945 39 26 66 Pass 0.6051 34 22 64 Pass 0.6157 29 16 55 Pass 0.6263 22 10 45 Pass 0.6369 15 8 53 Pass 0.6475 8 7 87 Pass 0.6581 5 5 100 Pass 0.6687 5 3 60 Pass 0.6792 5 0 0 Pass 0.6898 5 0 0 Pass 0.7004 5 0 0 Pass Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:03 AM Page 14 0.7110 5 0 0 Pass 0.7216 5 0 0 Pass 0.7322 5 0 0 Pass 0.7428 4 0 0 Pass 0.7534 4 0 0 Pass 0.7640 4 0 0 Pass 0.7746 4 0 0 Pass 0.7852 3 0 0 Pass 0.7958 3 0 0 Pass 0.8064 3 0 0 Pass 0.8170 3 0 0 Pass 0.8275 3 0 0 Pass 0.8381 3 0 0 Pass 0.8487 3 0 0 Pass 0.8593 3 0 0 Pass 0.8699 3 0 0 Pass 0.8805 3 0 0 Pass 0.8911 3 0 0 Pass 0.9017 3 0 0 Pass 0.9123 3 0 0 Pass 0.9229 2 0 0 Pass 0.9335 2 0 0 Pass 0.9441 2 0 0 Pass 0.9547 2 0 0 Pass 0.9653 2 0 0 Pass 0.9759 2 0 0 Pass 0.9864 2 0 0 Pass 0.9970 2 0 0 Pass 1.0076 2 0 0 Pass 1.0182 1 0 0 Pass 1.0288 1 0 0 Pass 1.0394 1 0 0 Pass 1.0500 1 0 0 Pass 1.0606 1 0 0 Pass 1.0712 1 0 0 Pass 1.0818 1 0 0 Pass 1.0924 1 0 0 Pass 1.1030 1 0 0 Pass 1.1136 1 0 0 Pass 1.1242 1 0 0 Pass 1.1348 1 0 0 Pass 1.1453 1 0 0 Pass 1.1559 1 0 0 Pass 1.1665 1 0 0 Pass 1.1771 1 0 0 Pass 1.1877 1 0 0 Pass 1.1983 1 0 0 Pass Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:03 AM Page 15 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0.753 acre-feet On-line facility target flow:0.7542 cfs. Adjusted for 15 min:0.7542 cfs. Off-line facility target flow:0.4223 cfs. Adjusted for 15 min:0.4223 cfs. INFLOW TO POND Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:03 AM Page 16 LID Report Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:39 AM Page 17 POC 2 POC #2 was not reported because POC must exist in both scenarios and both scenarios must have been run. Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:39 AM Page 18 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. Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:39 AM Page 19 Appendix Predeveloped Schematic Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:41 AM Page 20 Mitigated Schematic Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 21 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1955 10 01 END 2011 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 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm.wdm MESSU 25 PreSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm.MES 27 PreSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm.L61 28 PreSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm.L62 30 POCSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 11 PERLND 12 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 EX WESTBASIN 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 *** 11 C, Forest, Mod 1 1 1 1 27 0 12 C, Forest, Steep 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 *** 11 0 0 1 0 0 0 0 0 0 0 0 0 12 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 ********* Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 22 11 0 0 4 0 0 0 0 0 0 0 0 0 1 9 12 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 *** 11 0 0 0 0 0 0 0 0 0 0 0 12 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 11 0 4.5 0.08 400 0.1 0.5 0.996 12 0 4.5 0.08 400 0.15 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 11 0 0 2 2 0 0 0 12 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 11 0.2 0.5 0.35 6 0.5 0.7 12 0.2 0.3 0.35 6 0.3 0.7 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 11 0 0 0 0 2.5 1 0 12 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 *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 23 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** EX WESTBASIN*** PERLND 11 5.693 COPY 501 12 PERLND 11 5.693 COPY 501 13 PERLND 12 0.832 COPY 501 12 PERLND 12 0.832 COPY 501 13 ******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 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 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 24 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 END MASS-LINK END RUN Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 25 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1955 10 01 END 2011 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 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm.wdm MESSU 25 MitSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm.MES 27 MitSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm.L61 28 MitSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm.L62 31 POCSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm2.dat 30 POCSummit at ThompsonCrk W Pond (6_525ac)Rfxwhm1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 13 IMPLND 2 IMPLND 4 IMPLND 6 IMPLND 9 PERLND 17 RCHRES 1 COPY 502 COPY 1 COPY 501 COPY 601 DISPLY 2 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 2 Dev West Pond MAX 1 2 31 9 1 Trapezoidal Pond 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 502 1 1 501 1 1 601 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 *** 13 C, Pasture, Flat 1 1 1 1 27 0 17 C, Lawn, Mod 1 1 1 1 27 0 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 26 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 13 0 0 1 0 0 0 0 0 0 0 0 0 17 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 ********* 13 0 0 4 0 0 0 0 0 0 0 0 0 1 9 17 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 *** 13 0 0 0 0 0 0 0 0 0 0 0 17 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 13 0 4.5 0.06 400 0.05 0.5 0.996 17 0 4.5 0.03 400 0.1 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 13 0 0 2 2 0 0 0 17 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 13 0.15 0.4 0.3 6 0.5 0.4 17 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 13 0 0 0 0 2.5 1 0 17 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 6 DRIVEWAYS/MOD 1 1 1 27 0 9 SIDEWALKS/MOD 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 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 27 4 0 0 1 0 0 0 6 0 0 1 0 0 0 9 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 0 1 9 4 0 0 4 0 0 0 1 9 6 0 0 4 0 0 0 1 9 9 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 4 0 0 0 0 0 6 0 0 0 0 0 9 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 6 400 0.05 0.1 0.08 9 400 0.05 0.1 0.08 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 2 0 0 4 0 0 6 0 0 9 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 2 0 0 4 0 0 6 0 0 9 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Dev West Pond*** PERLND 13 3.503 RCHRES 1 2 PERLND 13 3.503 RCHRES 1 3 IMPLND 2 1.303 RCHRES 1 5 IMPLND 4 1.882 RCHRES 1 5 IMPLND 6 0.585 RCHRES 1 5 IMPLND 9 0.38 RCHRES 1 5 Dev West Pond*** PERLND 13 3.503 COPY 502 12 PERLND 13 3.503 COPY 502 13 IMPLND 2 1.303 COPY 502 15 IMPLND 4 1.882 COPY 502 15 IMPLND 6 0.585 COPY 502 15 IMPLND 9 0.38 COPY 502 15 West Bypass*** Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 28 PERLND 17 0.172 COPY 501 12 PERLND 17 0.172 COPY 601 12 PERLND 17 0.172 COPY 501 13 PERLND 17 0.172 COPY 601 13 PERLND 13 0.666 COPY 501 12 PERLND 13 0.666 COPY 601 12 PERLND 13 0.666 COPY 501 13 PERLND 13 0.666 COPY 601 13 ******Routing****** PERLND 13 3.503 COPY 1 12 IMPLND 2 1.303 COPY 1 15 IMPLND 4 1.882 COPY 1 15 IMPLND 6 0.585 COPY 1 15 IMPLND 9 0.38 COPY 1 15 PERLND 13 3.503 COPY 1 13 RCHRES 1 1 COPY 501 16 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 502 OUTPUT MEAN 1 1 48.4 DISPLY 2 INPUT TIMSER 1 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 *** 1 Trapezoidal Pond-005 1 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 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 * * * * * * * * * * * * * * *** 1 0 1 0 0 4 0 0 0 0 0 0 0 0 0 2 2 2 2 2 END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.02 0.0 0.0 0.5 0.0 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 <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 29 1 0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES FTABLE 1 91 4 Depth Area Volume Outflow1 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (ft/sec) (Minutes)*** 0.000000 0.293371 0.000000 0.000000 0.088889 0.296146 0.026201 0.017507 0.177778 0.298933 0.052649 0.024758 0.266667 0.301734 0.079345 0.030323 0.355556 0.304548 0.106291 0.035014 0.444444 0.307375 0.133487 0.039146 0.533333 0.310215 0.160936 0.042883 0.622222 0.313068 0.188637 0.046319 0.711111 0.315934 0.216593 0.049517 0.800000 0.318813 0.244804 0.052521 0.888889 0.321706 0.273272 0.055361 0.977778 0.324611 0.301997 0.058064 1.066667 0.327529 0.330981 0.060645 1.155556 0.330461 0.360225 0.063122 1.244444 0.333405 0.389730 0.065505 1.333333 0.336363 0.419497 0.067804 1.422222 0.339333 0.449528 0.070027 1.511111 0.342317 0.479824 0.072183 1.600000 0.345314 0.510385 0.074275 1.688889 0.348323 0.541214 0.076311 1.777778 0.351346 0.572310 0.078293 1.866667 0.354382 0.603676 0.080226 1.955556 0.357431 0.635312 0.082114 2.044444 0.360493 0.667220 0.083960 2.133333 0.363568 0.699400 0.085766 2.222222 0.366656 0.731855 0.087534 2.311111 0.369758 0.764584 0.089268 2.400000 0.372872 0.797590 0.090968 2.488889 0.375999 0.830873 0.092637 2.577778 0.379140 0.864435 0.094277 2.666667 0.382293 0.898276 0.095889 2.755556 0.385460 0.932398 0.097474 2.844444 0.388639 0.966803 0.099034 2.933333 0.391832 1.001490 0.100569 3.022222 0.395037 1.036462 0.102082 3.111111 0.398256 1.071720 0.103572 3.200000 0.401488 1.107264 0.105041 3.288889 0.404733 1.143096 0.106490 3.377778 0.407991 1.179217 0.107919 3.466667 0.411262 1.215628 0.109330 3.555556 0.414546 1.252331 0.110723 3.644444 0.417843 1.289326 0.112098 3.733333 0.421153 1.326615 0.113457 3.822222 0.424476 1.364198 0.114800 3.911111 0.427812 1.402078 0.116127 4.000000 0.431162 1.440254 0.117439 4.088889 0.434524 1.478729 0.118737 4.177778 0.437900 1.517504 0.120021 4.266667 0.441288 1.556579 0.121291 4.355556 0.444690 1.595955 0.122548 4.444444 0.448104 1.635635 0.123792 4.533333 0.451532 1.675619 0.125024 4.622222 0.454973 1.715908 0.126244 4.711111 0.458427 1.756504 0.127452 4.800000 0.461894 1.797407 0.128648 4.888889 0.465373 1.838619 0.129834 4.977778 0.468866 1.880140 0.131009 5.066667 0.472373 1.921973 0.132174 5.155556 0.475892 1.964118 0.133328 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 30 5.244444 0.479424 2.006577 0.134473 5.333333 0.482969 2.049350 0.135607 5.422222 0.486527 2.092439 0.136733 5.511111 0.490099 2.135844 0.137849 5.600000 0.493683 2.179568 0.138956 5.688889 0.497281 2.223611 0.140055 5.777778 0.500891 2.267974 0.141145 5.866667 0.504515 2.312659 0.142226 5.955556 0.508151 2.357666 0.143300 6.044444 0.511801 2.402997 0.144365 6.133333 0.515464 2.448653 0.145423 6.222222 0.519140 2.494636 0.146473 6.311111 0.522829 2.540945 0.147515 6.400000 0.526531 2.587584 0.148550 6.488889 0.530246 2.634551 0.149579 6.577778 0.533974 2.681850 0.150600 6.666667 0.537715 2.729481 0.152550 6.755556 0.541469 2.777444 0.217245 6.844444 0.545236 2.825742 0.328317 6.933333 0.549017 2.874376 0.470650 7.022222 0.552810 2.923346 0.629691 7.111111 0.556616 2.972654 0.985365 7.200000 0.560436 3.022301 1.504178 7.288889 0.564268 3.072287 2.044966 7.377778 0.568114 3.122616 2.477705 7.466667 0.571973 3.173286 2.737719 7.555556 0.575844 3.224300 2.947941 7.644444 0.579729 3.275659 3.129729 7.733333 0.583627 3.327364 3.299415 7.822222 0.587538 3.379415 3.459142 7.911111 0.591462 3.431815 3.610488 8.000000 0.595399 3.484565 3.754654 END FTABLE 1 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 2 OUTPUT MEAN 1 1 48.4 WDM 702 FLOW ENGL REPL COPY 502 OUTPUT MEAN 1 1 48.4 WDM 802 FLOW ENGL REPL COPY 602 OUTPUT MEAN 1 1 48.4 WDM 902 FLOW ENGL REPL RCHRES 1 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 1 HYDR STAGE 1 1 1 WDM 1001 STAG ENGL REPL 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 COPY 601 OUTPUT MEAN 1 1 48.4 WDM 901 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 2 PERLND PWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 2 MASS-LINK 3 PERLND PWATER IFWO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 3 MASS-LINK 5 Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 31 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 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 MASS-LINK 16 RCHRES ROFLOW COPY INPUT MEAN END MASS-LINK 16 END MASS-LINK END RUN Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:43 AM Page 32 Predeveloped HSPF Message File Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:44 AM Page 33 Mitigated HSPF Message File Summit at ThompsonCrk W Pond (6_525ac)Rfxwhm 8/23/2024 10:23:44 AM Page 34 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 WWHM2012 PROJECT REPORT Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 2 General Model Information Project Name:Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR Site Name:Summit at Thompson Site Address:Berry Valley City:Yelm Report Date:9/26/2024 Gage:Eaton Creek Data Start:1955/10/01 Data End:2011/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2021/08/18 Version:4.2.18 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Low Flow Threshold for POC2:50 Percent of the 2 Year High Flow Threshold for POC2:50 Year Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 3 Landuse Basin Data Predeveloped Land Use Existing East Basin Bypass:No GroundWater:No Pervious Land Use acre A B, Forest, Mod 6.065 A B, Forest, Steep 1.197 A B, Lawn, Mod 1.755 Pervious Total 9.017 Impervious Land Use acre Impervious Total 0 Basin Total 9.017 Element Flows To: Surface Interflow Groundwater Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 4 Mitigated Land Use DEV EAST BASIN TO WQ Bypass:No GroundWater:No Pervious Land Use acre A B, Pasture, Flat 2.498 A B, Forest, Mod 1.863 A B, Lawn, Mod 1.755 A B, Forest, Steep 0.344 Pervious Total 6.46 Impervious Land Use acre ROADS MOD 0.654 ROOF TOPS FLAT 0.971 DRIVEWAYS MOD 0.298 SIDEWALKS MOD 0.226 Impervious Total 2.149 Basin Total 8.609 Element Flows To: Surface Interflow Groundwater East Pond East Pond Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 5 DEV DIRECTLY TO POND Bypass:No GroundWater:No Pervious Land Use acre Pervious Total 0 Impervious Land Use acre ROOF TOPS FLAT 0.138 Impervious Total 0.138 Basin Total 0.138 Element Flows To: Surface Interflow Groundwater East Pond East Pond Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 6 Routing Elements Predeveloped Routing Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 7 Mitigated Routing East Pond Bottom Length:69.01 ft. Bottom Width:55.65 ft. Depth:4 ft. Volume at riser head:0.3525 acre-feet. Infiltration On Infiltration rate:4 Infiltration safety factor:1 Total Volume Infiltrated (ac-ft.):434.146 Total Volume Through Riser (ac-ft.):0 Total Volume Through Facility (ac-ft.):434.146 Percent Infiltrated:100 Total Precip Applied to Facility:0 Total Evap From Facility:0 Side slope 1:3 To 1 Side slope 2:3 To 1 Side slope 3:3 To 1 Side slope 4:3 To 1 Discharge Structure Riser Height:3 ft. Riser Diameter:18 in. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.088 0.000 0.000 0.000 0.0444 0.088 0.003 0.000 0.355 0.0889 0.089 0.007 0.000 0.355 0.1333 0.090 0.011 0.000 0.355 0.1778 0.091 0.015 0.000 0.355 0.2222 0.092 0.020 0.000 0.355 0.2667 0.092 0.024 0.000 0.355 0.3111 0.093 0.028 0.000 0.355 0.3556 0.094 0.032 0.000 0.355 0.4000 0.095 0.036 0.000 0.355 0.4444 0.096 0.040 0.000 0.355 0.4889 0.096 0.045 0.000 0.355 0.5333 0.097 0.049 0.000 0.355 0.5778 0.098 0.053 0.000 0.355 0.6222 0.099 0.058 0.000 0.355 0.6667 0.100 0.062 0.000 0.355 0.7111 0.100 0.067 0.000 0.355 0.7556 0.101 0.071 0.000 0.355 0.8000 0.102 0.076 0.000 0.355 0.8444 0.103 0.080 0.000 0.355 0.8889 0.104 0.085 0.000 0.355 0.9333 0.104 0.090 0.000 0.355 0.9778 0.105 0.094 0.000 0.355 1.0222 0.106 0.099 0.000 0.355 1.0667 0.107 0.104 0.000 0.355 1.1111 0.108 0.108 0.000 0.355 1.1556 0.109 0.113 0.000 0.355 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 8 1.2000 0.110 0.118 0.000 0.355 1.2444 0.110 0.123 0.000 0.355 1.2889 0.111 0.128 0.000 0.355 1.3333 0.112 0.133 0.000 0.355 1.3778 0.113 0.138 0.000 0.355 1.4222 0.114 0.143 0.000 0.355 1.4667 0.115 0.148 0.000 0.355 1.5111 0.116 0.153 0.000 0.355 1.5556 0.116 0.159 0.000 0.355 1.6000 0.117 0.164 0.000 0.355 1.6444 0.118 0.169 0.000 0.355 1.6889 0.119 0.174 0.000 0.355 1.7333 0.120 0.180 0.000 0.355 1.7778 0.121 0.185 0.000 0.355 1.8222 0.122 0.190 0.000 0.355 1.8667 0.123 0.196 0.000 0.355 1.9111 0.124 0.201 0.000 0.355 1.9556 0.124 0.207 0.000 0.355 2.0000 0.125 0.212 0.000 0.355 2.0444 0.126 0.218 0.000 0.355 2.0889 0.127 0.224 0.000 0.355 2.1333 0.128 0.229 0.000 0.355 2.1778 0.129 0.235 0.000 0.355 2.2222 0.130 0.241 0.000 0.355 2.2667 0.131 0.247 0.000 0.355 2.3111 0.132 0.253 0.000 0.355 2.3556 0.133 0.258 0.000 0.355 2.4000 0.134 0.264 0.000 0.355 2.4444 0.135 0.270 0.000 0.355 2.4889 0.136 0.276 0.000 0.355 2.5333 0.137 0.282 0.000 0.355 2.5778 0.137 0.289 0.000 0.355 2.6222 0.138 0.295 0.000 0.355 2.6667 0.139 0.301 0.000 0.355 2.7111 0.140 0.307 0.000 0.355 2.7556 0.141 0.313 0.000 0.355 2.8000 0.142 0.320 0.000 0.355 2.8444 0.143 0.326 0.000 0.355 2.8889 0.144 0.333 0.000 0.355 2.9333 0.145 0.339 0.000 0.355 2.9778 0.146 0.345 0.000 0.355 3.0222 0.147 0.352 0.052 0.355 3.0667 0.148 0.359 0.273 0.355 3.1111 0.149 0.365 0.587 0.355 3.1556 0.150 0.372 0.970 0.355 3.2000 0.151 0.379 1.404 0.355 3.2444 0.152 0.385 1.877 0.355 3.2889 0.153 0.392 2.374 0.355 3.3333 0.154 0.399 2.882 0.355 3.3778 0.155 0.406 3.386 0.355 3.4222 0.156 0.413 3.871 0.355 3.4667 0.157 0.420 4.326 0.355 3.5111 0.158 0.427 4.737 0.355 3.5556 0.159 0.434 5.097 0.355 3.6000 0.160 0.441 5.401 0.355 3.6444 0.161 0.448 5.649 0.355 3.6889 0.162 0.455 5.848 0.355 3.7333 0.163 0.463 6.014 0.355 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 9 3.7778 0.164 0.470 6.249 0.355 3.8222 0.165 0.477 6.425 0.355 3.8667 0.166 0.485 6.597 0.355 3.9111 0.168 0.492 6.764 0.355 3.9556 0.169 0.500 6.927 0.355 4.0000 0.170 0.507 7.086 0.355 4.0444 0.171 0.515 7.242 0.355 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:04 AM Page 10 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:9.017 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:6.46 Total Impervious Area:2.287 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.067878 5 year 0.22687 10 year 0.414809 25 year 0.77357 50 year 1.144352 100 year 1.615649 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0 5 year 0 10 year 0 25 year 0 50 year 0 100 year 0 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1956 0.261 0.000 1957 0.316 0.000 1958 0.093 0.000 1959 0.044 0.000 1960 0.110 0.000 1961 0.244 0.000 1962 0.007 0.000 1963 0.475 0.000 1964 0.066 0.000 1965 0.190 0.000 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:43 AM Page 11 1966 0.021 0.000 1967 0.241 0.000 1968 0.069 0.000 1969 0.031 0.000 1970 0.058 0.000 1971 0.346 0.000 1972 0.772 0.000 1973 0.019 0.000 1974 0.093 0.000 1975 0.053 0.000 1976 0.109 0.000 1977 0.006 0.000 1978 0.206 0.000 1979 0.019 0.000 1980 0.072 0.000 1981 0.594 0.000 1982 0.075 0.000 1983 0.117 0.000 1984 0.104 0.000 1985 0.009 0.000 1986 0.167 0.000 1987 0.237 0.000 1988 0.007 0.000 1989 0.372 0.000 1990 0.033 0.000 1991 1.211 0.000 1992 0.172 0.000 1993 0.022 0.000 1994 0.007 0.000 1995 0.061 0.000 1996 0.286 0.000 1997 0.112 0.000 1998 0.388 0.000 1999 0.146 0.000 2000 0.031 0.000 2001 0.007 0.000 2002 0.003 0.000 2003 0.006 0.000 2004 0.077 0.000 2005 0.003 0.000 2006 0.022 0.000 2007 0.255 0.000 2008 0.007 0.000 2009 0.061 0.000 2010 0.039 0.000 2011 0.042 0.000 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 1.2110 0.0000 2 0.7717 0.0000 3 0.5942 0.0000 4 0.4748 0.0000 5 0.3879 0.0000 6 0.3717 0.0000 7 0.3455 0.0000 8 0.3158 0.0000 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:44 AM Page 12 9 0.2857 0.0000 10 0.2608 0.0000 11 0.2550 0.0000 12 0.2439 0.0000 13 0.2408 0.0000 14 0.2366 0.0000 15 0.2063 0.0000 16 0.1897 0.0000 17 0.1719 0.0000 18 0.1667 0.0000 19 0.1457 0.0000 20 0.1171 0.0000 21 0.1121 0.0000 22 0.1101 0.0000 23 0.1091 0.0000 24 0.1040 0.0000 25 0.0928 0.0000 26 0.0927 0.0000 27 0.0775 0.0000 28 0.0751 0.0000 29 0.0724 0.0000 30 0.0688 0.0000 31 0.0664 0.0000 32 0.0610 0.0000 33 0.0605 0.0000 34 0.0578 0.0000 35 0.0527 0.0000 36 0.0441 0.0000 37 0.0420 0.0000 38 0.0387 0.0000 39 0.0327 0.0000 40 0.0310 0.0000 41 0.0306 0.0000 42 0.0222 0.0000 43 0.0217 0.0000 44 0.0208 0.0000 45 0.0188 0.0000 46 0.0185 0.0000 47 0.0089 0.0000 48 0.0075 0.0000 49 0.0071 0.0000 50 0.0070 0.0000 51 0.0069 0.0000 52 0.0067 0.0000 53 0.0064 0.0000 54 0.0059 0.0000 55 0.0033 0.0000 56 0.0030 0.0000 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:44 AM Page 13 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.0339 424 0 0 Pass 0.0452 319 0 0 Pass 0.0564 241 0 0 Pass 0.0676 192 0 0 Pass 0.0788 160 0 0 Pass 0.0900 130 0 0 Pass 0.1012 106 0 0 Pass 0.1125 85 0 0 Pass 0.1237 72 0 0 Pass 0.1349 64 0 0 Pass 0.1461 56 0 0 Pass 0.1573 50 0 0 Pass 0.1685 43 0 0 Pass 0.1798 37 0 0 Pass 0.1910 34 0 0 Pass 0.2022 29 0 0 Pass 0.2134 25 0 0 Pass 0.2246 24 0 0 Pass 0.2358 23 0 0 Pass 0.2470 19 0 0 Pass 0.2583 17 0 0 Pass 0.2695 15 0 0 Pass 0.2807 15 0 0 Pass 0.2919 14 0 0 Pass 0.3031 14 0 0 Pass 0.3143 12 0 0 Pass 0.3256 10 0 0 Pass 0.3368 10 0 0 Pass 0.3480 8 0 0 Pass 0.3592 7 0 0 Pass 0.3704 6 0 0 Pass 0.3816 5 0 0 Pass 0.3929 4 0 0 Pass 0.4041 4 0 0 Pass 0.4153 4 0 0 Pass 0.4265 4 0 0 Pass 0.4377 4 0 0 Pass 0.4489 4 0 0 Pass 0.4602 4 0 0 Pass 0.4714 4 0 0 Pass 0.4826 3 0 0 Pass 0.4938 3 0 0 Pass 0.5050 3 0 0 Pass 0.5162 3 0 0 Pass 0.5275 3 0 0 Pass 0.5387 3 0 0 Pass 0.5499 3 0 0 Pass 0.5611 3 0 0 Pass 0.5723 3 0 0 Pass 0.5835 3 0 0 Pass 0.5948 3 0 0 Pass 0.6060 2 0 0 Pass 0.6172 2 0 0 Pass Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:44 AM Page 14 0.6284 2 0 0 Pass 0.6396 2 0 0 Pass 0.6508 2 0 0 Pass 0.6621 2 0 0 Pass 0.6733 2 0 0 Pass 0.6845 2 0 0 Pass 0.6957 2 0 0 Pass 0.7069 2 0 0 Pass 0.7181 2 0 0 Pass 0.7293 2 0 0 Pass 0.7406 2 0 0 Pass 0.7518 2 0 0 Pass 0.7630 2 0 0 Pass 0.7742 1 0 0 Pass 0.7854 1 0 0 Pass 0.7966 1 0 0 Pass 0.8079 1 0 0 Pass 0.8191 1 0 0 Pass 0.8303 1 0 0 Pass 0.8415 1 0 0 Pass 0.8527 1 0 0 Pass 0.8639 1 0 0 Pass 0.8752 1 0 0 Pass 0.8864 1 0 0 Pass 0.8976 1 0 0 Pass 0.9088 1 0 0 Pass 0.9200 1 0 0 Pass 0.9312 1 0 0 Pass 0.9425 1 0 0 Pass 0.9537 1 0 0 Pass 0.9649 1 0 0 Pass 0.9761 1 0 0 Pass 0.9873 1 0 0 Pass 0.9985 1 0 0 Pass 1.0098 1 0 0 Pass 1.0210 1 0 0 Pass 1.0322 1 0 0 Pass 1.0434 1 0 0 Pass 1.0546 1 0 0 Pass 1.0658 1 0 0 Pass 1.0771 1 0 0 Pass 1.0883 1 0 0 Pass 1.0995 1 0 0 Pass 1.1107 1 0 0 Pass 1.1219 1 0 0 Pass 1.1331 1 0 0 Pass 1.1444 1 0 0 Pass Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:44 AM Page 15 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0.3614 acre-feet On-line facility target flow:0.4389 cfs. Adjusted for 15 min:0.4389 cfs. Off-line facility target flow:0.2476 cfs. Adjusted for 15 min:0.2476 cfs. INFLOW TO WATER QUALITY STRUCTURE Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:22:44 AM Page 16 LID Report Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:04 AM Page 17 POC 2 POC #2 was not reported because POC must exist in both scenarios and both scenarios must have been run. Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:04 AM Page 18 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. Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:04 AM Page 19 Appendix Predeveloped Schematic Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:06 AM Page 20 Mitigated Schematic Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 21 Predeveloped UCI File Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 22 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1955 10 01 END 2011 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 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR.wdm MESSU 25 MitSummit at ThompsonCrk EPond(8_747ac)flots3'rNoBR.MES 27 MitSummit at ThompsonCrk EPond(8_747ac)flots3'rNoBR.L61 28 MitSummit at ThompsonCrk EPond(8_747ac)flots3'rNoBR.L62 31 POCSummit at ThompsonCrk EPond(8_747ac)flots3'rNoBR2.dat 30 POCSummit at ThompsonCrk EPond(8_747ac)flots3'rNoBR1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 4 PERLND 2 PERLND 8 PERLND 3 IMPLND 2 IMPLND 4 IMPLND 6 IMPLND 9 RCHRES 1 COPY 502 COPY 1 COPY 501 DISPLY 2 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 2 DEV EAST BASIN TO WQ MAX 1 2 31 9 1 East Pond MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 502 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 *** 4 A/B, Pasture, Flat 1 1 1 1 27 0 2 A/B, Forest, Mod 1 1 1 1 27 0 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 23 8 A/B, Lawn, Mod 1 1 1 1 27 0 3 A/B, Forest, Steep 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 *** 4 0 0 1 0 0 0 0 0 0 0 0 0 2 0 0 1 0 0 0 0 0 0 0 0 0 8 0 0 1 0 0 0 0 0 0 0 0 0 3 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 ********* 4 0 0 4 0 0 0 0 0 0 0 0 0 1 9 2 0 0 4 0 0 0 0 0 0 0 0 0 1 9 8 0 0 4 0 0 0 0 0 0 0 0 0 1 9 3 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 *** 4 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 8 0 0 0 0 0 0 0 0 0 0 0 3 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 4 0 5 1.5 400 0.05 0.3 0.996 2 0 5 2 400 0.1 0.3 0.996 8 0 5 0.8 400 0.1 0.3 0.996 3 0 5 2 400 0.15 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 4 0 0 2 2 0 0 0 2 0 0 2 2 0 0 0 8 0 0 2 2 0 0 0 3 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 4 0.15 0.5 0.3 0 0.7 0.4 2 0.2 0.5 0.35 0 0.7 0.7 8 0.1 0.5 0.25 0 0.7 0.25 3 0.2 0.5 0.35 0 0.7 0.7 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 4 0 0 0 0 3 1 0 2 0 0 0 0 3 1 0 8 0 0 0 0 3 1 0 3 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 24 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 6 DRIVEWAYS/MOD 1 1 1 27 0 9 SIDEWALKS/MOD 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 6 0 0 1 0 0 0 9 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 0 1 9 4 0 0 4 0 0 0 1 9 6 0 0 4 0 0 0 1 9 9 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 4 0 0 0 0 0 6 0 0 0 0 0 9 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 6 400 0.05 0.1 0.08 9 400 0.05 0.1 0.08 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 2 0 0 4 0 0 6 0 0 9 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 2 0 0 4 0 0 6 0 0 9 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 25 <Name> # <-factor-> <Name> # Tbl# *** DEV EAST BASIN TO WQ*** PERLND 4 2.498 RCHRES 1 2 PERLND 4 2.498 RCHRES 1 3 PERLND 2 1.863 RCHRES 1 2 PERLND 2 1.863 RCHRES 1 3 PERLND 8 1.755 RCHRES 1 2 PERLND 8 1.755 RCHRES 1 3 PERLND 3 0.344 RCHRES 1 2 PERLND 3 0.344 RCHRES 1 3 IMPLND 2 0.654 RCHRES 1 5 IMPLND 4 0.971 RCHRES 1 5 IMPLND 6 0.298 RCHRES 1 5 IMPLND 9 0.226 RCHRES 1 5 DEV DIRECTLY TO POND*** IMPLND 4 0.138 RCHRES 1 5 DEV EAST BASIN TO WQ*** PERLND 4 2.498 COPY 502 12 PERLND 4 2.498 COPY 502 13 PERLND 2 1.863 COPY 502 12 PERLND 2 1.863 COPY 502 13 PERLND 8 1.755 COPY 502 12 PERLND 8 1.755 COPY 502 13 PERLND 3 0.344 COPY 502 12 PERLND 3 0.344 COPY 502 13 IMPLND 2 0.654 COPY 502 15 IMPLND 4 0.971 COPY 502 15 IMPLND 6 0.298 COPY 502 15 IMPLND 9 0.226 COPY 502 15 ******Routing****** PERLND 4 2.498 COPY 1 12 PERLND 2 1.863 COPY 1 12 PERLND 8 1.755 COPY 1 12 PERLND 3 0.344 COPY 1 12 IMPLND 2 0.654 COPY 1 15 IMPLND 4 0.971 COPY 1 15 IMPLND 6 0.298 COPY 1 15 IMPLND 9 0.226 COPY 1 15 PERLND 4 2.498 COPY 1 13 PERLND 2 1.863 COPY 1 13 PERLND 8 1.755 COPY 1 13 PERLND 3 0.344 COPY 1 13 IMPLND 4 0.138 COPY 1 15 RCHRES 1 1 COPY 501 17 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 502 OUTPUT MEAN 1 1 48.4 DISPLY 2 INPUT TIMSER 1 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 *** 1 East Pond 2 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 26 # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 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 * * * * * * * * * * * * * * *** 1 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.01 0.0 0.0 0.5 0.0 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 <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> 1 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES FTABLE 1 91 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.088165 0.000000 0.000000 0.000000 0.044444 0.088930 0.003935 0.000000 0.355601 0.088889 0.089698 0.007905 0.000000 0.355601 0.133333 0.090470 0.011909 0.000000 0.355601 0.177778 0.091244 0.015947 0.000000 0.355601 0.222222 0.092022 0.020019 0.000000 0.355601 0.266667 0.092803 0.024127 0.000000 0.355601 0.311111 0.093588 0.028269 0.000000 0.355601 0.355556 0.094375 0.032446 0.000000 0.355601 0.400000 0.095166 0.036658 0.000000 0.355601 0.444444 0.095960 0.040905 0.000000 0.355601 0.488889 0.096758 0.045187 0.000000 0.355601 0.533333 0.097558 0.049506 0.000000 0.355601 0.577778 0.098362 0.053859 0.000000 0.355601 0.622222 0.099170 0.058249 0.000000 0.355601 0.666667 0.099980 0.062675 0.000000 0.355601 0.711111 0.100794 0.067136 0.000000 0.355601 0.755556 0.101611 0.071634 0.000000 0.355601 0.800000 0.102431 0.076168 0.000000 0.355601 0.844444 0.103255 0.080739 0.000000 0.355601 0.888889 0.104082 0.085347 0.000000 0.355601 0.933333 0.104912 0.089991 0.000000 0.355601 0.977778 0.105745 0.094672 0.000000 0.355601 1.022222 0.106582 0.099391 0.000000 0.355601 1.066667 0.107421 0.104146 0.000000 0.355601 1.111111 0.108265 0.108939 0.000000 0.355601 1.155556 0.109111 0.113770 0.000000 0.355601 1.200000 0.109961 0.118638 0.000000 0.355601 1.244444 0.110814 0.123544 0.000000 0.355601 1.288889 0.111670 0.128488 0.000000 0.355601 1.333333 0.112529 0.133470 0.000000 0.355601 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 27 1.377778 0.113392 0.138491 0.000000 0.355601 1.422222 0.114258 0.143550 0.000000 0.355601 1.466667 0.115127 0.148647 0.000000 0.355601 1.511111 0.116000 0.153783 0.000000 0.355601 1.555556 0.116876 0.158958 0.000000 0.355601 1.600000 0.117755 0.164172 0.000000 0.355601 1.644444 0.118637 0.169426 0.000000 0.355601 1.688889 0.119523 0.174718 0.000000 0.355601 1.733333 0.120411 0.180050 0.000000 0.355601 1.777778 0.121304 0.185421 0.000000 0.355601 1.822222 0.122199 0.190832 0.000000 0.355601 1.866667 0.123098 0.196283 0.000000 0.355601 1.911111 0.124000 0.201775 0.000000 0.355601 1.955556 0.124905 0.207306 0.000000 0.355601 2.000000 0.125813 0.212877 0.000000 0.355601 2.044444 0.126725 0.218489 0.000000 0.355601 2.088889 0.127640 0.224142 0.000000 0.355601 2.133333 0.128558 0.229835 0.000000 0.355601 2.177778 0.129480 0.235569 0.000000 0.355601 2.222222 0.130404 0.241344 0.000000 0.355601 2.266667 0.131332 0.247161 0.000000 0.355601 2.311111 0.132264 0.253018 0.000000 0.355601 2.355556 0.133198 0.258918 0.000000 0.355601 2.400000 0.134136 0.264858 0.000000 0.355601 2.444444 0.135077 0.270841 0.000000 0.355601 2.488889 0.136022 0.276865 0.000000 0.355601 2.533333 0.136969 0.282932 0.000000 0.355601 2.577778 0.137920 0.289040 0.000000 0.355601 2.622222 0.138874 0.295191 0.000000 0.355601 2.666667 0.139832 0.301385 0.000000 0.355601 2.711111 0.140792 0.307621 0.000000 0.355601 2.755556 0.141756 0.313900 0.000000 0.355601 2.800000 0.142723 0.320222 0.000000 0.355601 2.844444 0.143694 0.326586 0.000000 0.355601 2.888889 0.144668 0.332994 0.000000 0.355601 2.933333 0.145645 0.339446 0.000000 0.355601 2.977778 0.146625 0.345941 0.000000 0.355601 3.022222 0.147608 0.352479 0.052737 0.355601 3.066667 0.148595 0.359062 0.273695 0.355601 3.111111 0.149585 0.365688 0.587805 0.355601 3.155556 0.150579 0.372358 0.970000 0.355601 3.200000 0.151575 0.379073 1.404464 0.355601 3.244444 0.152575 0.385832 1.877310 0.355601 3.288889 0.153578 0.392635 2.374724 0.355601 3.333333 0.154585 0.399483 2.882519 0.355601 3.377778 0.155594 0.406376 3.386283 0.355601 3.422222 0.156607 0.413314 3.871856 0.355601 3.466667 0.157623 0.420297 4.326027 0.355601 3.511111 0.158643 0.427325 4.737392 0.355601 3.555556 0.159666 0.434398 5.097354 0.355601 3.600000 0.160692 0.441517 5.401220 0.355601 3.644444 0.161721 0.448682 5.649420 0.355601 3.688889 0.162753 0.455893 5.848795 0.355601 3.733333 0.163789 0.463149 6.013989 0.355601 3.777778 0.164828 0.470452 6.249853 0.355601 3.822222 0.165870 0.477801 6.425940 0.355601 3.866667 0.166916 0.485196 6.597328 0.355601 3.911111 0.167965 0.492638 6.764376 0.355601 3.955556 0.169017 0.500126 6.927396 0.355601 4.000000 0.170072 0.507661 7.086668 0.355601 END FTABLE 1 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 Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 28 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 2 OUTPUT MEAN 1 1 48.4 WDM 702 FLOW ENGL REPL COPY 502 OUTPUT MEAN 1 1 48.4 WDM 802 FLOW ENGL REPL RCHRES 1 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 1 HYDR O 1 1 1 WDM 1001 FLOW ENGL REPL RCHRES 1 HYDR O 2 1 1 WDM 1002 FLOW ENGL REPL RCHRES 1 HYDR STAGE 1 1 1 WDM 1003 STAG ENGL REPL 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 2 PERLND PWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 2 MASS-LINK 3 PERLND PWATER IFWO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 3 MASS-LINK 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 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 MASS-LINK 17 RCHRES OFLOW OVOL 1 COPY INPUT MEAN END MASS-LINK 17 END MASS-LINK END RUN Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 29 Predeveloped HSPF Message File Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 30 Mitigated HSPF Message File Summit at ThompsonCrk EPond(8_747ac)flots3'rNoBR 9/26/2024 9:23:08 AM Page 31 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 WWHM2012 PROJECT REPORT Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 2 General Model Information Project Name:Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 Site Name:Summit at Thompson Site Address:Berry Valley City:Yelm Report Date:8/26/2024 Gage:Eaton Creek Data Start:1955/10/01 Data End:2011/09/30 Timestep:Hourly Precip Scale:1.000 Version Date:2021/08/18 Version:4.2.18 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Low Flow Threshold for POC2:50 Percent of the 2 Year High Flow Threshold for POC2:50 Year Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 3 Landuse Basin Data Predeveloped Land Use EX SOUTH POND Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Mod 10.034 C, Lawn, Mod 2.449 Pervious Total 12.483 Impervious Land Use acre Impervious Total 0 Basin Total 12.483 Element Flows To: Surface Interflow Groundwater Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 4 Mitigated Land Use Dev South Pond Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Mod 0.479 C, Pasture, Flat 3.009 C, Lawn, Mod 2.448 Pervious Total 5.936 Impervious Land Use acre ROADS FLAT 0.705 ROADS MOD 0.261 ROOF TOPS FLAT 1.522 DRIVEWAYS FLAT 0.416 SIDEWALKS FLAT 0.08 SIDEWALKS MOD 0.046 Impervious Total 3.03 Basin Total 8.966 Element Flows To: Surface Interflow Groundwater Trapezoidal Pond 1 Trapezoidal Pond 1 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 5 South Bypass Bypass:Yes GroundWater:No Pervious Land Use acre C, Pasture, Flat 1.151 Pervious Total 1.151 Impervious Land Use acre Impervious Total 0 Basin Total 1.151 Element Flows To: Surface Interflow Groundwater Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 6 Routing Elements Predeveloped Routing Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 7 Mitigated Routing Trapezoidal Pond 1 Bottom Length:114.26 ft. Bottom Width:114.26 ft. Depth:4 ft. Volume at riser head:1.0571 acre-feet. Side slope 1:3 To 1 Side slope 2:3 To 1 Side slope 3:3 To 1 Side slope 4:3 To 1 Discharge Structure Riser Height:3 ft. Riser Diameter:12 in. Notch Type:Rectangular Notch Width:0.490 ft. Notch Height:0.637 ft. Orifice 1 Diameter:3.052 in.Elevation:0 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.299 0.000 0.000 0.000 0.0444 0.301 0.013 0.053 0.000 0.0889 0.302 0.026 0.075 0.000 0.1333 0.303 0.040 0.092 0.000 0.1778 0.305 0.053 0.106 0.000 0.2222 0.306 0.067 0.119 0.000 0.2667 0.308 0.081 0.130 0.000 0.3111 0.309 0.094 0.141 0.000 0.3556 0.311 0.108 0.150 0.000 0.4000 0.312 0.122 0.159 0.000 0.4444 0.313 0.136 0.168 0.000 0.4889 0.315 0.150 0.176 0.000 0.5333 0.316 0.164 0.184 0.000 0.5778 0.318 0.178 0.192 0.000 0.6222 0.319 0.192 0.199 0.000 0.6667 0.321 0.206 0.206 0.000 0.7111 0.322 0.221 0.213 0.000 0.7556 0.323 0.235 0.219 0.000 0.8000 0.325 0.250 0.226 0.000 0.8444 0.326 0.264 0.232 0.000 0.8889 0.328 0.279 0.238 0.000 0.9333 0.329 0.293 0.244 0.000 0.9778 0.331 0.308 0.249 0.000 1.0222 0.332 0.323 0.255 0.000 1.0667 0.334 0.337 0.261 0.000 1.1111 0.335 0.352 0.266 0.000 1.1556 0.337 0.367 0.271 0.000 1.2000 0.338 0.382 0.276 0.000 1.2444 0.340 0.397 0.282 0.000 1.2889 0.341 0.413 0.287 0.000 1.3333 0.343 0.428 0.291 0.000 1.3778 0.344 0.443 0.296 0.000 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 8 1.4222 0.346 0.458 0.301 0.000 1.4667 0.347 0.474 0.306 0.000 1.5111 0.349 0.489 0.310 0.000 1.5556 0.350 0.505 0.315 0.000 1.6000 0.352 0.520 0.319 0.000 1.6444 0.353 0.536 0.324 0.000 1.6889 0.355 0.552 0.328 0.000 1.7333 0.356 0.568 0.332 0.000 1.7778 0.358 0.584 0.337 0.000 1.8222 0.359 0.600 0.341 0.000 1.8667 0.361 0.616 0.345 0.000 1.9111 0.362 0.632 0.349 0.000 1.9556 0.364 0.648 0.353 0.000 2.0000 0.366 0.664 0.357 0.000 2.0444 0.367 0.680 0.361 0.000 2.0889 0.369 0.697 0.365 0.000 2.1333 0.370 0.713 0.369 0.000 2.1778 0.372 0.730 0.373 0.000 2.2222 0.373 0.746 0.376 0.000 2.2667 0.375 0.763 0.380 0.000 2.3111 0.376 0.780 0.384 0.000 2.3556 0.378 0.796 0.387 0.000 2.4000 0.380 0.813 0.403 0.000 2.4444 0.381 0.830 0.432 0.000 2.4889 0.383 0.847 0.471 0.000 2.5333 0.384 0.864 0.516 0.000 2.5778 0.386 0.881 0.567 0.000 2.6222 0.387 0.899 0.624 0.000 2.6667 0.389 0.916 0.685 0.000 2.7111 0.391 0.933 0.750 0.000 2.7556 0.392 0.951 0.820 0.000 2.8000 0.394 0.968 0.893 0.000 2.8444 0.395 0.986 0.971 0.000 2.8889 0.397 1.003 1.051 0.000 2.9333 0.399 1.021 1.135 0.000 2.9778 0.400 1.039 1.222 0.000 3.0222 0.402 1.057 1.303 0.000 3.0667 0.404 1.075 1.454 0.000 3.1111 0.405 1.093 1.665 0.000 3.1556 0.407 1.111 1.915 0.000 3.2000 0.408 1.129 2.189 0.000 3.2444 0.410 1.147 2.468 0.000 3.2889 0.412 1.165 2.735 0.000 3.3333 0.413 1.184 2.974 0.000 3.3778 0.415 1.202 3.173 0.000 3.4222 0.417 1.221 3.326 0.000 3.4667 0.418 1.239 3.438 0.000 3.5111 0.420 1.258 3.554 0.000 3.5556 0.422 1.276 3.653 0.000 3.6000 0.423 1.295 3.748 0.000 3.6444 0.425 1.314 3.840 0.000 3.6889 0.427 1.333 3.928 0.000 3.7333 0.428 1.352 4.014 0.000 3.7778 0.430 1.371 4.098 0.000 3.8222 0.432 1.390 4.179 0.000 3.8667 0.433 1.410 4.258 0.000 3.9111 0.435 1.429 4.335 0.000 3.9556 0.437 1.448 4.410 0.000 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 9 4.0000 0.438 1.468 4.484 0.000 4.0444 0.440 1.487 4.556 0.000 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:13 PM Page 10 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:12.483 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:7.087 Total Impervious Area:3.03 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.673162 5 year 1.058263 10 year 1.33378 25 year 1.700549 50 year 1.985369 100 year 2.278933 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.441242 5 year 0.679344 10 year 0.871636 25 year 1.158214 50 year 1.406132 100 year 1.685974 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1956 0.817 0.428 1957 1.455 0.908 1958 0.431 0.258 1959 0.589 0.377 1960 0.925 0.957 1961 0.559 0.387 1962 0.202 0.238 1963 1.358 0.786 1964 0.552 0.402 1965 0.771 0.331 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:33 PM Page 11 1966 0.325 0.271 1967 0.631 0.394 1968 0.487 0.342 1969 0.273 0.280 1970 0.510 0.370 1971 0.746 0.461 1972 1.472 0.846 1973 0.559 0.400 1974 0.702 0.316 1975 0.404 0.294 1976 1.030 0.524 1977 0.223 0.188 1978 0.884 0.369 1979 0.521 0.358 1980 0.597 0.409 1981 1.821 0.439 1982 0.590 0.440 1983 1.073 0.484 1984 0.586 0.391 1985 0.263 0.259 1986 1.041 0.974 1987 1.063 0.901 1988 0.357 0.346 1989 1.666 0.369 1990 0.912 0.679 1991 1.336 1.349 1992 0.643 0.354 1993 1.336 0.386 1994 0.393 0.270 1995 0.940 0.842 1996 1.325 1.555 1997 0.560 0.399 1998 1.638 0.417 1999 0.962 0.575 2000 0.559 0.366 2001 0.524 0.429 2002 0.293 0.265 2003 0.616 0.865 2004 1.166 1.147 2005 0.442 0.354 2006 0.600 0.394 2007 1.040 0.872 2008 0.526 0.441 2009 1.005 1.124 2010 0.280 0.341 2011 0.386 0.310 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 1.8211 1.5550 2 1.6657 1.3485 3 1.6376 1.1468 4 1.4717 1.1241 5 1.4551 0.9742 6 1.3584 0.9568 7 1.3365 0.9082 8 1.3357 0.9010 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:33 PM Page 12 9 1.3251 0.8716 10 1.1663 0.8655 11 1.0730 0.8465 12 1.0629 0.8421 13 1.0412 0.7855 14 1.0402 0.6793 15 1.0296 0.5752 16 1.0054 0.5242 17 0.9615 0.4838 18 0.9400 0.4614 19 0.9248 0.4409 20 0.9119 0.4402 21 0.8839 0.4389 22 0.8173 0.4290 23 0.7706 0.4282 24 0.7459 0.4170 25 0.7020 0.4092 26 0.6428 0.4020 27 0.6310 0.4001 28 0.6162 0.3995 29 0.5999 0.3942 30 0.5974 0.3937 31 0.5898 0.3909 32 0.5894 0.3874 33 0.5860 0.3860 34 0.5602 0.3772 35 0.5589 0.3701 36 0.5589 0.3689 37 0.5585 0.3689 38 0.5518 0.3659 39 0.5260 0.3582 40 0.5239 0.3541 41 0.5215 0.3536 42 0.5097 0.3456 43 0.4872 0.3421 44 0.4418 0.3410 45 0.4308 0.3312 46 0.4043 0.3158 47 0.3928 0.3101 48 0.3856 0.2939 49 0.3571 0.2796 50 0.3249 0.2712 51 0.2933 0.2696 52 0.2797 0.2648 53 0.2733 0.2593 54 0.2627 0.2579 55 0.2226 0.2382 56 0.2024 0.1876 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:33 PM Page 13 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.3366 2798 2764 98 Pass 0.3532 2443 2192 89 Pass 0.3699 2181 1748 80 Pass 0.3865 1917 1333 69 Pass 0.4032 1682 966 57 Pass 0.4199 1498 724 48 Pass 0.4365 1330 495 37 Pass 0.4532 1174 381 32 Pass 0.4698 1049 339 32 Pass 0.4865 944 307 32 Pass 0.5031 835 281 33 Pass 0.5198 740 261 35 Pass 0.5364 646 241 37 Pass 0.5531 571 224 39 Pass 0.5697 516 207 40 Pass 0.5864 452 190 42 Pass 0.6031 403 176 43 Pass 0.6197 357 169 47 Pass 0.6364 317 157 49 Pass 0.6530 285 145 50 Pass 0.6697 257 133 51 Pass 0.6863 234 119 50 Pass 0.7030 209 115 55 Pass 0.7196 188 110 58 Pass 0.7363 164 103 62 Pass 0.7529 148 96 64 Pass 0.7696 137 90 65 Pass 0.7863 124 81 65 Pass 0.8029 116 74 63 Pass 0.8196 107 69 64 Pass 0.8362 99 65 65 Pass 0.8529 90 57 63 Pass 0.8695 86 52 60 Pass 0.8862 76 47 61 Pass 0.9028 68 44 64 Pass 0.9195 60 41 68 Pass 0.9361 56 39 69 Pass 0.9528 51 35 68 Pass 0.9694 47 32 68 Pass 0.9861 43 30 69 Pass 1.0028 39 28 71 Pass 1.0194 36 27 75 Pass 1.0361 32 26 81 Pass 1.0527 29 24 82 Pass 1.0694 27 20 74 Pass 1.0860 25 20 80 Pass 1.1027 23 17 73 Pass 1.1193 22 17 77 Pass 1.1360 21 16 76 Pass 1.1526 18 14 77 Pass 1.1693 17 13 76 Pass 1.1860 17 13 76 Pass 1.2026 16 13 81 Pass Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:33 PM Page 14 1.2193 15 12 80 Pass 1.2359 15 12 80 Pass 1.2526 12 11 91 Pass 1.2692 12 11 91 Pass 1.2859 12 10 83 Pass 1.3025 11 9 81 Pass 1.3192 11 9 81 Pass 1.3358 10 9 90 Pass 1.3525 8 7 87 Pass 1.3692 7 7 100 Pass 1.3858 7 7 100 Pass 1.4025 6 6 100 Pass 1.4191 5 5 100 Pass 1.4358 5 5 100 Pass 1.4524 5 4 80 Pass 1.4691 4 3 75 Pass 1.4857 3 2 66 Pass 1.5024 3 2 66 Pass 1.5190 3 2 66 Pass 1.5357 3 2 66 Pass 1.5524 3 1 33 Pass 1.5690 3 0 0 Pass 1.5857 3 0 0 Pass 1.6023 3 0 0 Pass 1.6190 3 0 0 Pass 1.6356 3 0 0 Pass 1.6523 2 0 0 Pass 1.6689 1 0 0 Pass 1.6856 1 0 0 Pass 1.7022 1 0 0 Pass 1.7189 1 0 0 Pass 1.7356 1 0 0 Pass 1.7522 1 0 0 Pass 1.7689 1 0 0 Pass 1.7855 1 0 0 Pass 1.8022 1 0 0 Pass 1.8188 1 0 0 Pass 1.8355 0 0 0 Pass 1.8521 0 0 0 Pass 1.8688 0 0 0 Pass 1.8854 0 0 0 Pass 1.9021 0 0 0 Pass 1.9188 0 0 0 Pass 1.9354 0 0 0 Pass 1.9521 0 0 0 Pass 1.9687 0 0 0 Pass 1.9854 0 0 0 Pass Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:33 PM Page 15 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0.7062 acre-feet On-line facility target flow:0.59 cfs. Adjusted for 15 min:0.59 cfs. Off-line facility target flow:0.3266 cfs. Adjusted for 15 min:0.3266 cfs. INFLOW TO POND Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:33 PM Page 16 LID Report Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:44 PM Page 17 POC 2 POC #2 was not reported because POC must exist in both scenarios and both scenarios must have been run. Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:44 PM Page 18 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. Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:44 PM Page 19 Appendix Predeveloped Schematic Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:46 PM Page 20 Mitigated Schematic Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 21 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1955 10 01 END 2011 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 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.wdm MESSU 25 PreSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.MES 27 PreSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.L61 28 PreSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.L62 30 POCSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t11.dat END FILES OPN SEQUENCE INGRP INDELT 00:60 PERLND 11 PERLND 17 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 EX SOUTH POND 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 *** 11 C, Forest, Mod 1 1 1 1 27 0 17 C, Lawn, Mod 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 *** 11 0 0 1 0 0 0 0 0 0 0 0 0 17 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 ********* Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 22 11 0 0 4 0 0 0 0 0 0 0 0 0 1 9 17 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 *** 11 0 0 0 0 0 0 0 0 0 0 0 17 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 11 0 4.5 0.08 400 0.1 0.5 0.996 17 0 4.5 0.03 400 0.1 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 11 0 0 2 2 0 0 0 17 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 11 0.2 0.5 0.35 6 0.5 0.7 17 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 11 0 0 0 0 2.5 1 0 17 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 *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 23 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** EX SOUTH POND*** PERLND 11 10.034 COPY 501 12 PERLND 11 10.034 COPY 501 13 PERLND 17 2.449 COPY 501 12 PERLND 17 2.449 COPY 501 13 ******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 12.1 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 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 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 24 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 SUM PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 SUM 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 12.1 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 END MASS-LINK END RUN Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 25 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1955 10 01 END 2011 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 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.wdm MESSU 25 MitSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.MES 27 MitSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.L61 28 MitSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1.L62 31 POCSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t12.dat 30 POCSumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t11.dat END FILES OPN SEQUENCE INGRP INDELT 00:60 PERLND 11 PERLND 13 PERLND 17 IMPLND 1 IMPLND 2 IMPLND 4 IMPLND 5 IMPLND 8 IMPLND 9 RCHRES 1 COPY 502 COPY 1 COPY 501 COPY 601 DISPLY 2 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 2 Dev South Pond MAX 1 2 31 9 1 Trapezoidal Pond 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 502 1 1 501 1 1 601 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 *** Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 26 in out *** 11 C, Forest, Mod 1 1 1 1 27 0 13 C, Pasture, Flat 1 1 1 1 27 0 17 C, Lawn, Mod 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 *** 11 0 0 1 0 0 0 0 0 0 0 0 0 13 0 0 1 0 0 0 0 0 0 0 0 0 17 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 ********* 11 0 0 4 0 0 0 0 0 0 0 0 0 1 9 13 0 0 4 0 0 0 0 0 0 0 0 0 1 9 17 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 *** 11 0 0 0 0 0 0 0 0 0 0 0 13 0 0 0 0 0 0 0 0 0 0 0 17 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 11 0 4.5 0.08 400 0.1 0.5 0.996 13 0 4.5 0.06 400 0.05 0.5 0.996 17 0 4.5 0.03 400 0.1 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 11 0 0 2 2 0 0 0 13 0 0 2 2 0 0 0 17 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 11 0.2 0.5 0.35 6 0.5 0.7 13 0.15 0.4 0.3 6 0.5 0.4 17 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 11 0 0 0 0 2.5 1 0 13 0 0 0 0 2.5 1 0 17 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 *** Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 27 1 ROADS/FLAT 1 1 1 27 0 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 9 SIDEWALKS/MOD 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 1 0 0 1 0 0 0 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 9 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 1 0 0 4 0 0 0 1 9 2 0 0 4 0 0 0 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 9 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 *** 1 0 0 0 0 0 2 0 0 0 0 0 4 0 0 0 0 0 5 0 0 0 0 0 8 0 0 0 0 0 9 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 1 400 0.01 0.1 0.1 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 9 400 0.05 0.1 0.08 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 1 0 0 2 0 0 4 0 0 5 0 0 8 0 0 9 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 1 0 0 2 0 0 4 0 0 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 28 5 0 0 8 0 0 9 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Dev South Pond*** PERLND 11 0.479 RCHRES 1 2 PERLND 11 0.479 RCHRES 1 3 PERLND 13 3.009 RCHRES 1 2 PERLND 13 3.009 RCHRES 1 3 PERLND 17 2.448 RCHRES 1 2 PERLND 17 2.448 RCHRES 1 3 IMPLND 1 0.705 RCHRES 1 5 IMPLND 2 0.261 RCHRES 1 5 IMPLND 4 1.522 RCHRES 1 5 IMPLND 5 0.416 RCHRES 1 5 IMPLND 8 0.08 RCHRES 1 5 IMPLND 9 0.046 RCHRES 1 5 Dev South Pond*** PERLND 11 0.479 COPY 502 12 PERLND 11 0.479 COPY 502 13 PERLND 13 3.009 COPY 502 12 PERLND 13 3.009 COPY 502 13 PERLND 17 2.448 COPY 502 12 PERLND 17 2.448 COPY 502 13 IMPLND 1 0.705 COPY 502 15 IMPLND 2 0.261 COPY 502 15 IMPLND 4 1.522 COPY 502 15 IMPLND 5 0.416 COPY 502 15 IMPLND 8 0.08 COPY 502 15 IMPLND 9 0.046 COPY 502 15 South Bypass*** PERLND 13 1.151 COPY 501 12 PERLND 13 1.151 COPY 601 12 PERLND 13 1.151 COPY 501 13 PERLND 13 1.151 COPY 601 13 ******Routing****** PERLND 11 0.479 COPY 1 12 PERLND 13 3.009 COPY 1 12 PERLND 17 2.448 COPY 1 12 IMPLND 1 0.705 COPY 1 15 IMPLND 2 0.261 COPY 1 15 IMPLND 4 1.522 COPY 1 15 IMPLND 5 0.416 COPY 1 15 IMPLND 8 0.08 COPY 1 15 IMPLND 9 0.046 COPY 1 15 PERLND 11 0.479 COPY 1 13 PERLND 13 3.009 COPY 1 13 PERLND 17 2.448 COPY 1 13 RCHRES 1 1 COPY 501 16 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 502 OUTPUT MEAN 1 1 12.1 DISPLY 2 INPUT TIMSER 1 COPY 501 OUTPUT MEAN 1 1 12.1 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 29 RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** 1 Trapezoidal Pond-005 1 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 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 * * * * * * * * * * * * * * *** 1 0 1 0 0 4 0 0 0 0 0 0 0 0 0 2 2 2 2 2 END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.02 0.0 0.0 0.5 0.0 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 <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> 1 0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES FTABLE 1 91 4 Depth Area Volume Outflow1 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (ft/sec) (Minutes)*** 0.000000 0.299694 0.000000 0.000000 0.044444 0.301094 0.013351 0.053289 0.088889 0.302498 0.026764 0.075362 0.133333 0.303905 0.040240 0.092299 0.177778 0.305315 0.053778 0.106578 0.222222 0.306729 0.067379 0.119158 0.266667 0.308146 0.081043 0.130531 0.311111 0.309566 0.094770 0.140989 0.355556 0.310989 0.108560 0.150724 0.400000 0.312416 0.122413 0.159867 0.444444 0.313846 0.136330 0.168514 0.488889 0.315279 0.150311 0.176739 0.533333 0.316716 0.164355 0.184598 0.577778 0.318155 0.178463 0.192136 0.622222 0.319598 0.192636 0.199389 0.666667 0.321045 0.206872 0.206387 0.711111 0.322494 0.221173 0.213155 0.755556 0.323947 0.235538 0.219716 0.800000 0.325403 0.249968 0.226086 0.844444 0.326862 0.264463 0.232281 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 30 0.888889 0.328325 0.279023 0.238315 0.933333 0.329791 0.293648 0.244200 0.977778 0.331260 0.308338 0.249947 1.022222 0.332732 0.323093 0.255564 1.066667 0.334208 0.337914 0.261061 1.111111 0.335687 0.352800 0.266444 1.155556 0.337169 0.367753 0.271721 1.200000 0.338654 0.382771 0.276897 1.244444 0.340143 0.397855 0.281978 1.288889 0.341635 0.413006 0.286969 1.333333 0.343130 0.428223 0.291875 1.377778 0.344629 0.443507 0.296700 1.422222 0.346131 0.458857 0.301447 1.466667 0.347636 0.474274 0.306121 1.511111 0.349144 0.489758 0.310725 1.555556 0.350656 0.505309 0.315261 1.600000 0.352170 0.520927 0.319733 1.644444 0.353688 0.536613 0.324144 1.688889 0.355210 0.552366 0.328495 1.733333 0.356734 0.568187 0.332789 1.777778 0.358262 0.584076 0.337028 1.822222 0.359794 0.600033 0.341215 1.866667 0.361328 0.616058 0.345351 1.911111 0.362866 0.632151 0.349438 1.955556 0.364407 0.648313 0.353478 2.000000 0.365951 0.664543 0.357473 2.044444 0.367498 0.680842 0.361423 2.088889 0.369049 0.697209 0.365330 2.133333 0.370603 0.713646 0.369196 2.177778 0.372160 0.730152 0.373022 2.222222 0.373721 0.746727 0.376809 2.266667 0.375285 0.763372 0.380559 2.311111 0.376852 0.780086 0.384272 2.355556 0.378422 0.796870 0.387949 2.400000 0.379996 0.813723 0.402997 2.444444 0.381572 0.830647 0.432834 2.488889 0.383153 0.847641 0.471315 2.533333 0.384736 0.864705 0.516651 2.577778 0.386323 0.881840 0.567851 2.622222 0.387913 0.899045 0.624261 2.666667 0.389506 0.916321 0.685406 2.711111 0.391102 0.933668 0.750921 2.755556 0.392702 0.951086 0.820516 2.800000 0.394305 0.968575 0.893950 2.844444 0.395911 0.986135 0.971021 2.888889 0.397521 1.003767 1.051556 2.933333 0.399133 1.021470 1.135405 2.977778 0.400749 1.039246 1.222434 3.022222 0.402369 1.057093 1.303870 3.066667 0.403991 1.075012 1.454176 3.111111 0.405617 1.093003 1.664977 3.155556 0.407246 1.111067 1.915633 3.200000 0.408879 1.129203 2.189139 3.244444 0.410514 1.147412 2.468151 3.288889 0.412153 1.165693 2.735195 3.333333 0.413795 1.184048 2.974255 3.377778 0.415441 1.202475 3.173124 3.422222 0.417089 1.220976 3.326288 3.466667 0.418741 1.239550 3.438252 3.511111 0.420397 1.258197 3.554668 3.555556 0.422055 1.276918 3.653517 3.600000 0.423717 1.295713 3.748584 3.644444 0.425382 1.314582 3.840281 3.688889 0.427050 1.333525 3.928948 3.733333 0.428722 1.352542 4.014874 3.777778 0.430397 1.371634 4.098303 3.822222 0.432075 1.390800 4.179446 3.866667 0.433756 1.410040 4.258483 3.911111 0.435441 1.429356 4.335575 3.955556 0.437128 1.448746 4.410861 Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 31 4.000000 0.438820 1.468212 4.484464 END FTABLE 1 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 SUM PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 SUM 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 2 OUTPUT MEAN 1 1 12.1 WDM 702 FLOW ENGL REPL COPY 502 OUTPUT MEAN 1 1 12.1 WDM 802 FLOW ENGL REPL COPY 602 OUTPUT MEAN 1 1 12.1 WDM 902 FLOW ENGL REPL RCHRES 1 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 1 HYDR STAGE 1 1 1 WDM 1001 STAG ENGL REPL COPY 1 OUTPUT MEAN 1 1 12.1 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 12.1 WDM 801 FLOW ENGL REPL COPY 601 OUTPUT MEAN 1 1 12.1 WDM 901 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 2 PERLND PWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 2 MASS-LINK 3 PERLND PWATER IFWO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 3 MASS-LINK 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 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 MASS-LINK 16 RCHRES ROFLOW COPY INPUT MEAN END MASS-LINK 16 END MASS-LINK END RUN Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 32 Predeveloped HSPF Message File Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 33 Mitigated HSPF Message File Sumat TCrk S Pond (8_97ac1_15BP L25-39hlf)4ft3t1 8/26/2024 12:57:48 PM Page 34 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 Roof Drain Conveyance Q= CIA C= 0.9 25-yr 100-yr Basin Area(sf)Area(ac)Q 25yr(cfs)Q 100yr(cfs) I=2.982936 iph I=2.982936 I=3.733248 Lots 17-24 14,700 0.337 0.906 1.134 A=14700 sf m 7 m 8.86 Lots 25-31 16,800 0.386 1.035 1.296 A=0.337466 ac n 0.53 n 0.537 Lots 4-12 17,400 0.399 1.072 1.342 Tc(min)5 Tc(min)5 Lots 66-72 15,600 0.358 0.961 1.203 Q= B6 Preliminary Stormwater Report The Summit at Thompson Creek 2220471.11 Appendix C Geotechnical Engineering Report South Sound Geotechnical Consulting, Inc. June 16, 2022 Geotechnical Seasonal Groundwater Monitoring (Winter 2022-2023) South Sound Geotechnical Consulting, Inc. May 12, 2023 South Sound Geotechnical Consulting P.O. Box 39500, Lakewood, WA 98496 (253) 973-0515 June 16, 2022 Mr. Matt Weber c/o AHBL 2215 North 30th Street, Suite 200 Tacoma, Washington 98403-3350 Subject: Geotechnical Engineering Report The Summit at Thompson Creek 14444 Berry Valley Road Yelm, Washington SSGC Project No. 22029 Mr. Weber, South Sound Geotechnical Consulting (SSGC) has completed a geotechnical assessment for the planned development at the above addressed property in Yelm, Washington. Our services have been completed in general conformance with our proposal P21150 (dated March 31, 2022) and authorized per signature of our agreement for services. Our scope of services included completion of twenty test pits and one infiltration test on the site, laboratory testing, engineering analyses, and preparation of this report. PROJECT INFORMATION The site is composed of several individual parcels totaling about 30 acres, west of the current terminus of Berry Valley Road. Development plans include dividing the properties into 93 individual single-family lots. SITE CONDITIONS The eastern portion of the site is lower in elevation and generally level. This area is grass field. The western portion is characterized by a southwest-northeast trending knoll. An existing residence and several outbuildings are in the eastern side of the western portion. The remainder of the western portion is undeveloped and partially forested. Overall elevation change across the site is on the order of 70 (+/-) feet from the highest point on the knoll in the western portion to the lower eastern portion of the site. Elevation change in the western portion is on the order of 50 feet (+/-). SUBSURFACE CONDITIONS Subsurface conditions were characterized by completing twenty test pits and one infiltration test on April 14, 2022. Explorations were advanced to final depths between 2.5 and 11 feet below existing ground surface. Approximate locations of the explorations are shown on Figure 1, Exploration Plan. A summary description of observed subgrade conditions is provided below. Logs of the test holes are provided in Appendix A. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 2 Soil Conditions Topsoil and isolated fill was at the surface of the test pits and extended to depths between 6 inches and 2.5 feet. Native soils below the topsoil/fill varied across the site. In general, the lower eastern portion contains loose sandy gravel with cobbles, occasional boulders and minor fines. These soils are considered to be outwash deposits and extended to the termination depth of the test holes in this area. Native soils in the western portion consisted of upper layers of soft to stiff clayey silt (interpreted as glacial lake deposits) or outwash over glacial till/drift consisting of silty sand with gravel and variable cobbles. Upper soils extended to depths from less than 1 foot to about 5 feet. Till/drift was in a medium dense grading to very dense condition and extended to the termination depth of the test pits, where encountered. Groundwater Conditions Groundwater was observed in test pit TP-17 (adjacent infiltration test PIT-1 in the lower eastern portion) near Thompson Creek at an elevation of about 7 feet at the time of excavation. Seepage was observed in several of the test pits in the western portion above the glacial till/drift. Groundwater levels and seepage will vary throughout the year due to seasonal precipitation and on- and off-site drainage patterns. Geologic Setting Soil types mapped on the site per the USDA Soil Conservation Service map of Thurston County consist of both glacial outwash and glacial drift. Outwash soils are generally mapped in the lower eastern portion of the site, with drift in the higher western portion. Native soils appear to generally conform to the mapped soil types. GEOTECHNICAL DESIGN CONSIDERATIONS The planned development is considered feasible based on observed soil conditions in the test pits. Properly prepared native soils are considered suitable for support of conventional spread footing foundations, slab- on-grade floors, and conventional pavements. Native (outwash) soils are suitable for infiltration, where encountered. Soils with higher fines content and drift/till are predominant in the higher elevated western portion. These soils will limit infiltration facilities to shallow dispersion or detention systems. Infiltration is not feasible in the silty (lake deposits) or dense drift/till soils. Depth to seasonally high groundwater levels should be considered in the design of infiltration facilities in the lower eastern portion. We anticipate grading (cuts and fills) will be used to modify existing topography for final design grades of the development, particularly in the western portion. Final grades should be considered relative to the feasibility of infiltration systems. Recommendations presented in the following sections should be considered general and may require modifications when earthwork and grading occur. They are based upon the subsurface conditions observed Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 3 in the test pits and the assumption that finish site grades will be similar to existing grades. It should be noted that subsurface conditions across the site may vary from those depicted on the exploration logs and can change with time. Therefore, proper site preparation will depend upon the weather and soil conditions encountered at the time of construction. We recommend SSGC review final plans and assess subgrade conditions at the time of construction. General Site Preparation Site grading and earthwork should include procedures to control surface water runoff. Grading the site without adequate drainage control measures may negatively impact site soils, resulting in increased export of impacted soil and import of fill materials, thereby potentially increasing the cost of the earthwork and subgrade preparation phases of the project. Site grading should include removal of all fill and any organic materials in future building and pavement areas. Subgrades should consist of firm native soils following stripping. Final stripping depths can only be determined at the time of earthwork. General Subgrade Preparation Subgrades in building and pavement areas should consist of firm native soil or compacted structural fill. We recommend exposed subgrades in building and conventional pavement areas are proofrolled using a large roller, loaded dump truck, or other mechanical equipment to assess subgrade conditions following stripping. Proofrolling efforts should result in the upper 1 foot of subgrade soils achievin g a firm and unyielding condition and a compaction level of at least 92 percent of the maximum dry density (MDD) per the ASTM D1557 test method. Wet, loose, or soft subgrades that cannot achieve this compaction level should be removed (over-excavated) and replaced with structural fill. The depth of over-excavation should be based on soil conditions at the time of construction. A representative of SSGC should be present to assess subgrade conditions during proofrolling. Grading and Drainage Positive drainage should be provided during construction and maintained throughout the life of the development. Surface water should not be allowed into cut/fill areas, utility trenches, building footprints, or pavement areas. Structural Fill Materials The suitability of soil for use as structural fill will depend on the gradation and moisture content of the soil when it is placed. Soils with higher fines content (soil fraction passing the U.S. No. 200 sieve) will become sensitive with higher moisture content. It is often difficult to achieve adequate compaction if soil moisture is outside of optimum ranges for soils that contain more than about 5 percent fines. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 4 Site Soils: Topsoil is not considered suitable for structural fill and should be wasted from the site or used in landscape areas. The clayey silt and glacial till/drift will be difficult to use due to higher fines content of these soils. Native outwash soil is generally considered suitable for use as structural. Soils with higher fines content could be used provided they can be moisture conditioned to within optimal ranges. Silt content will vary in the native soils and can make them moisture sensitive, requiring conditioning (drying or wetting) to obtain optimum moisture content. Optimum moisture is considered within about +/- 2 percent of the moisture content required to achieve the maximum density per the ASTM D-1557 test method. Import Fill Materials: We recommend imported structural fill placed during dry weather consist of material which meets the specifications for Gravel Borrow as described in Section 9-03.14(1) of the Washington State Department of Transportation (WSDOT) Specifications for Road, Bridge, and Municipal Construction manual (Publication M41-10). Gravel Borrow should be protected from disturbance if exposed to wet conditions after placement. During wet weather, or for backfill on wet subgrades, import soil suitable for compaction in wetter conditions should be provided. Imported fill for use in wet conditions should conform to specifications for Select Borrow as described in Section 9-03.14(2), or Crushed Surfacing per Section 9-03.9(3) of the WSDOT M41-10 manual, with the modification that a maximum of 5 percent by weight shall pass the U.S. No. 200 sieve for these soil types. Structural fill placement and compaction is weather-dependent. Delays due to inclement weather are common, even when using select granular fill. We recommend site grading and earthwork be scheduled for the drier months of the year. Structural fill should not consist of frozen material. Structural Fill Placement We recommend structural fill is placed in lifts not exceeding about 10 inches in loose measure. It may be necessary to adjust lift thickness based on site and fill conditions, and type of compaction equipment used during placement and compaction. Finer grained soil used as structural fill and/or lighter weight compaction equipment may require significantly thinner lifts to attain required compaction levels. Coarser granular soil with lower fines contents could potentially be placed in thicker lifts (1 foot maximum) if they can be adequately compacted. Structural fill should be compacted to attain the recommended levels presented in Table 1, Compaction Criteria. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 5 Table 1. Compaction Criteria Fill Application Compaction Criteria* Footing areas (below structures and retaining walls) 95 % Upper 2 feet in pavement areas, slabs and sidewalks, and utility trenches 95 % Below 2 feet in pavement areas, slabs and sidewalks, and utility trenches 92 % Utility trenches or general fill in non-paved or -building areas 90 % *Per the ASTM D 1557 test method. Trench backfill within about 2 feet of utility lines should not be over-compacted to reduce the risk of damage to the line. In some instances the top of the utility line may be within 2 feet of the surface. Backfill in these circumstances should be compacted to a firm and unyielding condition. We recommend fill procedures include maintaining grades that promote drainage and do not allow ponding of water within the fill area. The contractor should protect compacted fill subgrades from disturbance during wet weather. In the event of rain during structural fill placement, the exposed fill surface should be allowed to dry prior to placement of additional fill. Alternatively, the we t soil can be removed. We recommend consideration be given to protecting haul routes and other high traffic areas with free-draining granular fill material (i.e. sand and gravel containing less than 5 percent fines) or quarry spalls to reduce the potential for disturbance to the subgrade during inclement weather. Structural fill placed on sloping ground should be constructed using a benched (stairstep) methodology. Benches should be cut level or with a slight downward incline into the slope in firm native soil. Benches should be at least 3 feet wide and wide enough to accommodate compaction equipment, and be a maximum of two feet high. Earthwork Procedures Conventional earthmoving equipment should be suitable for earthwork at this site. Earthwork may be difficult during periods of wet weather or if elevated soil moisture is present. Excavated site soils may not be suitable as structural fill depending on the soil moisture content and weather condit ions at the time of earthwork. If soils are stockpiled and wet weather is anticipated, the stockpile should be protected with securely anchored plastic sheeting. If stockpiled soils become unusable, it may become necessary to import clean, granular soils to complete wet weather site work. Wet or disturbed subgrade soils should be over-excavated to expose firm, non-yielding, non-organic soils and backfilled with compacted structural fill. We recommend the earthwork portion of this project be completed during extended periods of dry weather. If earthwork is completed during the wet season (typically late October through May) it may be necessary to take extra measures to protect subgrade soils. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 6 If earthwork takes place during freezing conditions, we recommend the exposed subgrade be allowed to thaw and be re-compacted prior to placing subsequent lifts of structural fill. Alternatively, the frozen soil can be removed to unfrozen soil and replaced with structural fill. The contractor is responsible for designing and constructing stable, temporary excavations (such as utility trenches) to maintain stability of excavation sides and bottoms. Excavations should be sloped or shored in the interest of safety following local and federal regulations, including current OSHA excavation and trench safety standards. Temporary excavation cuts should be sloped at inclinations of 1.5H:1V (Horizontal:Vertical) or flatter, unless the contractor can demonstrate the safety of steeper inclinations. Deeper excavations may require shoring. Permanent cut and fill slopes should be graded at inclinations of 2H:1V, or flatter. A geotechnical engineer and accredited testing material laboratory should be retained during the construction phase of the project to observe earthwork operations and to perform necessary tests and observations during subgrade preparation, placement and compaction of structural fill, and backfilling of excavations. Foundations Foundations can be placed on native soils or on structural fill above prepared native subgrades as described in this report. The following recommendations are for conventional spread footing foundations: Bearing Capacity (net allowable): 2,000 pounds per square foot (psf) for footings supported firm native soils or structural fill over native subgrades prepared as described in this report. Footing Width (Minimum): 18 inches (Strip) 24 inches (Column) Embedment Depth (Minimum): 18 inches (Exterior) 12 inches (Interior) Settlement: Total: < 1 inch Differential: < 1/2 inch (over 30 feet) Allowable Lateral Passive Resistance: 300 psf/ft* (below 18 inches) Allowable Coefficient of Friction: 0.35* *These values include a factor of safety of approximately 1.5. The net allowable bearing pressures presented above may be increased by one-third to resist transient, dynamic loads such as wind or seismic forces. Lateral resistance to footings should be ignored in the upper 12-inches from exterior finish grade. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 7 Foundation Construction Considerations All foundation subgrades should be free of water and loose soil prior to placing concrete, and should be prepared as recommended in this report. Concrete should be placed soon after excavating and compaction to reduce disturbance to bearing soils. Should soils at foundation level become excessively dry, disturbed, saturated, or frozen, the affected soil should be removed prior to placing concrete. We recommend SSGC observe all foundation subgrades prior to placement of concrete. Foundation Drainage Ground surface adjacent foundations should be sloped away from buildings. We recommend footing drains are installed around perimeter footings. Footing drains should include a minimum 4-inch diameter perforated rigid plastic or metal drain line installed at the base of the footing. The perforated drain lines should be connected to a tight line pipe that discharges to an approved storm drain receptor. The drain line should be surrounded by a zone of clean, free-draining granular material having less than 5 percent passing the No. 200 sieve or meeting the requirements of section 9-03.12(2) “Gravel Backfill for Walls” in the WSDOT M41-10 manual. The free-draining aggregate zone should be at least 12 inches wide and wrapped in filter fabric. The granular fill should extend to within 6 inches of final grade where it should be capped with compacted fill containing sufficient fines to reduce infiltration of surface water into the footing drains. Alternately, the ground surface can be paved with asphalt or concrete. Cleanouts are recommended for maintenance of the drain system. On-Grade Floor Slabs On-grade floor slabs should be placed on native soils or structural fill prepared as described in this report. We recommend a modulus subgrade reaction of 150 pounds per square inch per inch (psi/in) for native soil or compacted granular structural fill over native soil. We recommend a capillary break is provided between the prepared subgrade and bottom of slab. Capillary break material should be a minimum of 4 inches thick and consist of compacted clean, free-draining, well graded course sand and gravel. The capillary break material should contain less than 5 percent fines, based on that soil fraction passing the U.S. No. 4 sieve. Alternatively, a clean angular gravel such as No. 7 aggregate per Section 9-03.1(4) C of the WSDOT (M41-10) manual could be used for this purpose. We recommend positive separations and/or isolation joints are provided between slabs and foundations, and columns or utility lines to allow independent movement where needed. Backfill in interior trenches beneath slabs should be compacted in accordance with recommendations presented in this report. A vapor retarder should be considered beneath concrete slabs that will be covered with moisture sensitive or impervious coverings (such as tile, wood, etc.), or when the slab will support equipment or stored materials sensitive to moisture. We recommend the slab designer refer to ACI 302 and/or ACI 360 for procedures and limitations regarding the use and placement of vapor retarders. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 8 Seismic Considerations Seismic parameters and values in Table 2 are recommended based on the 2015 International Building Code (IBC). Table 2. Seismic Parameters PARAMETER VALUE 2018 International Building Code (IBC) Site Classification1 D Ss Spectral Acceleration for a Short Period 1.39 S1 Spectral Acceleration for a 1-Second Period 0.521g 1 Note: In general accordance with the 2018 International Building Code for risk categories I,II,III. IBC Site Class is based on the estimated characteristics of the upper 100 feet of the subsurface profile. Ss, and S1 values based on the OSHPD Seismic Design Maps website. Liquefaction Soil liquefaction is a condition where loose, typically granular soils located below the groundwater surface lose strength during ground shaking, and is often associated with earthquakes. The risk of liquefaction at this site is low for the design level earthquake based on the Thurston County Liquefaction Hazard Map, dated April 2011. A site-specific liquefaction analyses was not part of our scope and would be required to fully assess liquefaction potential and impacts. Infiltration Characteristics Infiltration facilities will be used to assist in control of stormwater, where feasible. An assessment of infiltration potential of the outwash in the lower eastern portion of the site was completed by performing one Pilot Infiltration Test per procedures in the Thurston County Drainage Design and Erosion Control Manual. Results of the test is presented in Table 3. Table 3. Infiltration Rates Sample ID and Depth (ft) Soil Type Measured Infiltration Rate (in/hr) Corrected Infiltration Rate (in/hr) Correction Factors* (Fg/Ft/Fp) PIT-1, 3 ft Outwash 62 28 (1.0/0.5/0.9) *Correction Factors from the Thurston County Drainage Design and Erosion Control Manual. The measured infiltration rate is considered appropriate for the soil tested and are similar to infiltration tests completed at other sites with similar soil throughout Thurston County. We recommend a design infiltration rate of 28 inches per hour (in/hr) for native outwash soils. However, groundwater was encountered at about Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 9 7 feet below the surface in this area and should be considered in the design of infiltration facilities. Infiltration in the clayey silt and till soils is not considered feasible. Additional infiltration assessment may be necessary in other portions of the site to assess infiltration potential once final grades have been established. Cation Exchange Capacity (CEC) and organic content tests were completed on samples of the outwash soil. Test results are summarized in the table below. Table 4. CEC and Organic Content Results Test Site, Sample Number, Depth CEC Results (milliequivalents) CEC Required* (milliequivalents) Organic Content Results (%) Organic Content Required* (%) TP-1, S-1, 3 ft 13.3 ≥ 5 5.30 ≥1.0 PIT-1, S-1, 3 ft 13.5 5.45 * Values from the Thurston County Drainage Design and Erosion Control Manual. Organic content and CEC results of the tested samples satisfy County requirements. Conventional Pavement Sections Subgrades for conventional pavements should be prepared as described in the “Subgrade Preparation” and “Structural Fill” sections of this report. Subgrades below pavement sections should be graded or crowned to promote drainage and not allow for ponding of water beneath the section. If drainage is not provided and ponding occurs, subgrade soils could become saturated, lose strength, and result in premature distress or failure of the section. In addition, the pavement surfacing should also be graded to promote drainage and reduce the potential for ponding of water on the pavement surface. We recommend a separation fabric (such as Mirafi N180, or other) is placed on roads underlain by clayey silt subgrades prior to placement of pavement section materials. The purpose of the fabric is to maintain segregation of the coarser fill and the lower finer grained native soil. Coarser fill will have the tendency to migrate into the looser native soil over time which can compromise the structural integrity of the pavement section fill and result in premature distress in the pavement without the separation fabric. Separation fabric is not considered necessary in roadways underlain by till or outwash. Minimum recommended pavement sections for conventional asphalt or concrete pavements are presented in Table 5. Pavement sections in public right-of-ways should be designed per City of Yelm (or Thurston County) standards. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 10 Table 5. Preliminary Pavement Sections Traffic Area Minimum Recommended Pavement Section Thickness (inches) Asphalt Concrete Surface1 Portland Cement Concrete2 Aggregate Base Course3,4 Subbase Aggregate5 Driveways 2 4 4 12 Access Roads 3 6 6 12 1 1/2 –inch nominal aggregate hot-mix asphalt (HMA) per WSDOT 9-03.8(1) 2 A 28 day minimum compressive strength of 4,000 psi and an allowable flexural strength of at least 250 psi 3 Crushed Surfacing Base Course per WSDOT 9-03.9(3) 4Although not required for structural support under concrete pavements, a minimum four-inch thick base course layer is recommended to help reduce potentials for slab curl, shrinkage cracking, and subgrade “pumping” through joints 5 Gravel Borrow per WSDOT 9-03.14(1) or Permeable Ballast WSDOT 9-03.9(1) or native soil compacted to 95% of ASTM D-1557 Conventional Pavement Maintenance The performance and lifespan of pavements can be significantly impacted by future maintenance. The above pavement sections represent minimum recommended thicknesses and, as such, periodic maintenance should be completed. Proper maintenance will slow the rate of pavement deterioration, and will improve pavement performance and life. Preventive maintenance consists of both localized maintenance (crack and joint sealing and patching) and global maintenance (surface sealing). Added maintenance measures and reduced pavement life should be anticipated over the lifetime of pavements if any existing fill or topsoil is left in-place beneath pavement sections. REPORT CONDITIONS This report has been prepared for the exclusive use of Mr. Matt Weber for specific application to the project discussed, and has been prepared in accordance with generally accepted geotechnical engineering practices in the area. No warranties, either express or implied, are intended or made. The analysis and recommendations presented in this report are based on observed soil conditions and test results at the indicated locations, and from other geologic information discussed. This report does not reflect variations that may occur across the site, or due to the modifying effects of construction, or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. This report was prepared for the planned type of development of the site as discussed herein. It is not valid for third party entities or alternate types of development on the site without the express written consent of Geotechnical Engineering Report The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 SSGC SSGC. If development plans change we should be notified to review those changes and modify our recommendations as necessary. The scope of services for this project does not include any environmental or biological assessment of the site including identification or prevention of pollutants, hazardous materials, or conditions. Other studies should be completed if the owner is concerned about the potential for contamination or pollution. We appreciate the opportunity to work with you on this project. Please contact us if additional information is required or we can be of further assistance. Respectfully, South Sound GeoteMchnical Consulting RO Timothy H. Roberts, P.E. Member/Geotechnical Engineer Attachments: Figure 1 — Exploration Plan Appendix A — Field Exploration Procedures and Test Pit Logs Appendix B — Laboratory Testing and Results Unified Soil Classification System TP-1 South Sound Geotechnical Consulting P.O. Box 39500 Lakewood, WA 98496 (253) 973-0515 Figure 1 – Exploration Plan The Summit at Thompson Creek Yelm, WA SSGC Project #22029 Base map from sheet drawing titled “Preliminary Site Plan - The Summit at Thompson Creek ”, by Informed AHBL, dated 3-16-22. N Legend Approximate Test Pit Location No Scale PIT - 1 PIT - 1 Approximate Infiltration Test Location TP-10 TP-4 TP-1 TP-5 TP-6 TP-3 TP-2 TP-9 TP-8 TP-11 TP-12 TP-13 TP-14 TP-15 TP-16 TP-17 TP-18 TP-19 TP-20 TP-7 Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 Appendix A Field Exploration Procedures and Test Pit Logs Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 A-1 Field Exploration Procedures Our field exploration for this project included twenty test pits and one Pilot Infiltration Test completed on April 14, 2022. The approximate locations of the explorations are shown on Figure 1, Exploration Plan. Test pit locations were determined by pacing from site features. Ground surface elevations referenced on the logs were inferred from topographic data from Google Earth satellite imagery and the Thurston County GIS. Test pit locations and elevations should be considered accurate only to the degree implied by the means and methods used. A private excavation company dug the test pits. Soil samples were collected and stored in moisture tight containers for further assessment and laboratory testing. Explorations were backfilled with excavated soils and tamped when completed. Please note that backfill in the explorations may settle with time. Backfill material located in roads or building areas should be re-excavated and recompacted, or replaced with structural fill. The following logs indicate the observed lithology of soils and other materials observed in the explorations at the time of excavation. Where a soil contact was observed to be gradational, our log indicates the average contact depth. Our logs also indicate the approximate depth to groundwater (where observed at the time of excavation), along with sample numbers and approximate sample depths. Soil descriptions on the logs are based on the Unified Soil Classification System. Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 1 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-1 Depth (feet) Material Description 0 – 1 1 – 4.5 4.5 – 5 Topsoil Fine to coarse sandy GRAVEL with some cobbles: Loose, moist, brown. (GP)(Glacial Outwash)(Sample S-1 @ 3 feet) Silty SAND with some gravel and a few cobbles: Medium dense, moist, gray. (SM) (Glacial Till). Test pit completed at approximately 5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 380 feet Test Pit TP-2 Depth (feet) Material Description 0 – 1 1 – 4.5 4.5 – 5.5 Topsoil Clayey SILT/Silty CLAY with some fine gravel: Soft to stiff, moist, mottled reddish brown to gray. (ML/CL) (Glacial Lake Deposits). Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 5.5 feet on 4/14/22. Slight seepage at 4 feet at time of excavation. Approximate surface elevation: 360 feet. Test Pit TP-3 Depth (feet) Material Description 0 – 1.0 1.0 – 4.5 4.5 – 5.5 Topsoil Sandy GRAVEL with trace to some silt and occasional cobble: Loose, moist, brown grading gray. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, gray. (SM) (Glacial Till). Test pit completed at approximately 5.5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 360 feet Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 2 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-4 Depth (feet) Material Description 0 – 1 1 – 3 3 – 4 Topsoil Sandy GRAVEL with trace to some silt and occasional cobble: Loose, moist, brown grading gray. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, gray. (SM) (Glacial Till). Test pit completed at approximately 4 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 365 feet Test Pit TP-5 Depth (feet) Material Description 0 – 1 1 – 4 4 – 5.5 Topsoil Sandy GRAVEL with trace to some silt and occasional cobble: Loose, moist, reddish brown. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, gray. (SM) (Glacial Till). Test pit completed at approximately 5.5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 380 feet Test Pit TP-6 Depth (feet) Material Description 0 – 0.5 0.5 – 1.5 1.5 – 2.5 Topsoil Sandy GRAVEL with trace to some silt and occasional cobble: Loose, moist, reddish brown. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 2.5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 395 feet Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 3 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-7 Depth (feet) Material Description 0 – 2.5 2.5 – 4 4 – 4.5 Topsoil/fill Organic silt, sand, gravel: Loose, moist dark brown. Silty SAND with gravel and some cobbles: Medium dense to dense, moist, mottled brown to gray. (SM) (Weathered Glacial Till). Silty SAND with gravel and cobbles: Dense to very dense, moist, gray, massive. (SM) (Glacial Till) Test pit completed at approximately 4.5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 380 feet Test Pit TP-8 Depth (feet) Material Description 0 – 0.5 0.5 – 4 Topsoil Silty SAND with gravel and a few cobbles: Medium dense to dense, moist, brown grading gray. (SM) (Glacial Till). Test pit completed at approximately 4 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 360 feet. Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 4 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-9 Depth (feet) Material Description 0 – 0.5 0.5 – 4 4 – 5 Topsoil Sandy GRAVEL with trace to some silt and occasional cobble: Loose, dry to moist, light brown grading gray. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 360 feet Test Pit TP-10 Depth (feet) Material Description 0 – 0.5 0.5 – 5 5 – 5.5 Topsoil Sandy GRAVEL with trace to some silt and occasional cobble: Loose, dry to moist, light brown grading gray. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 5.5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 360 feet Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 5 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-11 Depth (feet) Material Description 0 – 0.5 0.5 – 3 3 – 5 5 – 6 Topsoil Fine to coarse sandy GRAVEL and a few cobbles grades medium to coarse gravelly fine to medium sand at 2.0-3.0 feet: Loose, moist, brown. (SP/GP). (Outwash) Fine to medium SAND with a trace of gravel: Loose, moist, gray. (SP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 6 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 358 feet Test Pit TP-12 Depth (feet) Material Description 0 – 0.5 0.5 – 3.5 3.5 – 4 Topsoil Clayey SILT/Silty CLAY with some fine gravel: Soft to stiff, moist, reddish brown grading to gray at 4.0 feet (ML/CL) (Glacial Lake Deposits). Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 4 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 350 feet Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 6 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-13 Depth (feet) Material Description 0 – 0.5 0.5 – 2 2 – 5.5 Topsoil SILT with variable clay and fine gravel: Soft to stiff, moist, reddish brown grading to gray at 4.0 feet (ML) (Glacial Lake Deposits). Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 5.5 feet on 4/14/22. Moderate seepage at 2 feet observed at time of excavation. Approximate surface elevation: 350 feet Test Pit TP-14 Depth (feet) Material Description 0 – 0.5 0.5 – 5 5 – 6 Topsoil SILT with variable clay and fine gravel: Soft to stiff, moist, reddish brown grading to gray at 4.0 feet (ML) (Glacial Lake Deposits). Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 6 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 355 feet. Test Pit TP-15 Depth (feet) Material Description 0 – 0.5 0.5 – 4 4 – 5 Topsoil Sandy GRAVEL with some cobbles and a few boulders: Loose, dry to moist, light brown grading to gray at 3.0 feet. (GP) (Outwash) Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 5 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 355 feet Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 7 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-16 Depth (feet) Material Description 0 – 0.5 0.5 – 6 6 – 7 Topsoil SILT with variable clay and fine gravel: Soft to stiff, moist, reddish brown grading to gray at 4.0 feet (ML) (Glacial Lake Deposits). Silty SAND with gravel and a few cobbles: Dense, moist, brownish gray. (SM) (Glacial Till). Test pit completed at approximately 7 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 380 feet. Test Pit TP-17 Depth (feet) Material Description 0 – 0.5 0.5 – 11 Topsoil Cobbly fine to coarse GRAVEL with sand: Loose to medium dense, moist to wet, black grading to light brown below 3.0 feet. (GP) (Outwash) Test pit completed at approximately 11 feet on 4/14/22. Groundwater and sloughing observed at 7 feet at time of excavation. Approximate surface elevation: 335 feet. Test Pit TP-18 Depth (feet) Material Description 0 – 0.5 0.5 – 10 Topsoil Medium to coarse sandy GRAVEL with cobbles and boulders: Loose to medium dense, moist to wet at 9 feet, black grading to light brown below 3.0 feet. (GP) (Outwash). Test pit completed at approximately 10 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 335 feet. Project: Summit at Thompson Creek SSGC Job # 22029 EXPLORATION LOGS PAGE 8 OF 8 Location: 14444 Berry Valley Rd, Yelm, WA EXPLORATION LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 to TP-20, PIT-1 Logged by: THR Test Pit TP-19 Depth (feet) Material Description 0 – 0.5 0.5 – 8 Topsoil Medium to coarse sandy GRAVEL with cobbles and boulders: Loose, moist, black grading to light brown below 3.0 feet. (GP) (Outwash). Test pit completed at approximately 8 feet on 4/14/22. Groundwater not observed at time of excavation. Approximate surface elevation: 340 feet. Test Pit TP-20 Depth (feet) Material Description 0 – 0.5 0.5 – 5.0 Topsoil Medium to coarse sandy GRAVEL with cobbles and boulders: Loose, moist, black grading to light brown below 3.0 feet. (GP) (Outwash). Test pit completed at approximately 5 feet on 4/14/22 due to caving. Groundwater not observed at time of the excavation. Approximate surface elevation: 340 feet. Infiltration Test PIT-1 Depth (feet) Material Description 0 – 0.5 0.5 – 5 Topsoil Cobbly fine to coarse GRAVEL with boulders with some sand: Loose, moist, black grading to light brown below 3.0 feet. (GP) (Glacial Outwash) (Sample S-1 @ 3 feet). Test hole completed at approximately 5 feet on 4/14/22. Groundwater not observed at time of excavation. Infiltration test completed at 3 feet. Approximate surface elevation: 335 feet. Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 Appendix B Laboratory Testing and Results Geotechnical Engineering Report SSGC The Summit at Thompson Creek Yelm, Washington SSGC Project No. 22029 June 16, 2022 B-1 Laboratory Testing Select soil samples were tested for organic content and cation exchange capacity (CEC) by Northwest Agricultural Consultants of Kennewick, Washington. Results of the laboratory testing are included in this appendix. 2545 W Falls Avenue Kennewick, WA 99336 509.783.7450 www.nwag.com lab@nwag.com Sample ID Organic Matter Cation Exchange Capacity Pit-1, S-1 5.45% 13.5 meq/100g TP-1, S-1 5.30% 13.3 meq/100g Method ASTM D2974 EPA 9081 South Sound Geotechnical Consulting PO Box 39500 Lakewood, WA 98496 Report: 59040-1-1 Date: April 25, 2022 Project No: 22029 Project Name: Berry Valley South Sound Geotechnical Consulting P.O. Box 39500, Lakewood, WA 98496 (253) 973-0515 May 12, 2023 Mr. Matt Weber c/o AHBL 2215 North 30th Street, Suite 200 Tacoma, Washington 98403-3350 Subject: Seasonal Groundwater Monitoring (Winter 2022-2023) The Summit at Thompson Creek 14444 Berry Valley Road Yelm, Washington SSGC Project No. 22029 Mr. Weber, South Sound Geotechnical Consulting (SSGC) has completed monitoring of groundwater levels through the 2022-2023 winter season at the planned Summit at Thompson Creek development in Yelm, Washington. A piezometer was installed in one of the test pits (TP-17) in the proposed stormwater facility to monitor seasonal groundwater fluctuations through the 2022 – 2023 winter season. Approximate locations of all test holes are shown on Figure 1, Exploration Plan. Groundwater levels measured from the original date of setting the piezometers to April 2023 are presented in the table below. Test Hole Date Groundwater Level (Below Surface) TP-17 4/14/22 7’ 12/10/22 7’ 6” 1/15/23 7’ 4” 2/18/23 6’ 9” 3/18/23 6’ 10” 4/8/23 6’8” We recommend the April 2023 level observed in test pit TP-17 is used in design of stormwater control facilities for this site. Adjustments to groundwater levels for infiltration facilities should account for final grades of the site (cuts and fills that will impact existing surface grades). REPORT CONDITIONS This report has been prepared for the exclusive use of Matt Weber for specific application to the project discussed, and has been prepared in accordance with generally accepted geotechnical engineering practices in the area. No warranties, either express or implied, are intended or made of future groundwater conditions. Seasonal Groundwater Monitoring (Winter 2022-2023) The Summit at Thompson Ridge Yelm, Washington SSGC Project No. 22029 May 12, 2023 SSGC We appreciate the opportunity to work with you on this project. Please contact us if additional information is required or we can be of further assistance. Respectfully, South Sound Geotechnical Consulting Timothy H. Roberts, P.E. Member/Geotechnical Engineer Attachment: Figure 1 — Exploration Plan TP-1 South Sound Geotechnical Consulting P.O. Box 39500 Lakewood, WA 98496 (253) 973-0515 Figure 1 – Exploration Plan The Summit at Thompson Creek Yelm, WA SSGC Project #22029 Base map from sheet drawing titled “Preliminary Site Plan - The Summit at Thompson Creek ”, by Informed AHBL, dated 3-16-22. N Legend Approximate Test Pit Location No Scale PIT - 1 PIT - 1 Approximate Infiltration Test Location TP-10 TP-4 TP-1 TP-5 TP-6 TP-3 TP-2 TP-9 TP-8 TP-11 TP-12 TP-13 TP-14 TP-15 TP-16 TP-17 TP-18 TP-19 TP-20 TP-7 UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Soil Classification Group Symbol Group NameB Coarse Grained Soils More than 50% retained on No. 200 sieve Gravels More than 50% of coarse fraction retained on No. 4 sieve Clean Gravels Less than 5% finesC Cu  4 and 1  Cc  3E GW Well-graded gravelF Cu  4 and/or 1  Cc  3E GP Poorly graded gravelF Gravels with Fines More than 12% finesC Fines classify as ML or MH GM Silty gravelF,G, H Fines classify as CL or CH GC Clayey gravelF,G,H Sands 50% or more of coarse fraction passes No. 4 sieve Clean Sands Less than 5% finesD Cu  6 and 1  Cc  3E SW Well-graded sandI Cu  6 and/or 1  Cc  3E SP Poorly graded sandI Sands with Fines More than 12% finesD Fines classify as ML or MH SM Silty sandG,H,I Fines Classify as CL or CH SC Clayey sandG,H,I Fine-Grained Soils 50% or more passes the No. 200 sieve Silts and Clays Liquid limit less than 50 inorganic PI  7 and plots on or above “A” lineJ CL Lean clayK,L,M PI  4 or plots below “A” lineJ ML SiltK,L,M organic Liquid limit - oven dried  0.75 OL Organic clayK,L,M,N Liquid limit - not dried Organic siltK,L,M,O Silts and Clays Liquid limit 50 or more inorganic PI plots on or above “A” line CH Fat clayK,L,M PI plots below “A” line MH Elastic SiltK,L,M organic Liquid limit - oven dried  0.75 OH Organic clayK,L,M,P Liquid limit - not dried Organic siltK,L,M,Q Highly organic soils Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-in. (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW -GM well-graded gravel with silt, GW -GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW -SM well-graded sand with silt, SW -SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay E Cu = D60/D10 Cc = 6010 2 30 DxD )(D F If soil contains  15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. HIf fines are organic, add “with organic fines” to group name. I If soil contains  15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains  30% plus No. 200 predominantly sand, add “sandy” to group name. M If soil contains  30% plus No. 200, predominantly gravel, add “gravelly” to group name. N PI  4 and plots on or above “A” line. O PI  4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line.