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07 Preliminary Technical Information Report (TIR)
STORM DRAINAGE REPORT For 2200 SW 320th Street Federal Way, 98023 Applicant: Skyline Properties Inc. 1851 Central PL S, Suite 116 Kent, WA 98031 Engineer: Ted Dimof, PE License No. 36042 Bush, Roed and Hitchings 2009 Minor Avenue E Seattle, WA 98102 (206) 323-4144 Date: March 18th, 2019 Page | 2 Table of Contents 1.0 – PROJECT OVERVIEW ......................................................................................................................... 4 2.0 – CONDITIONS AND REQUIREMENTS SUMMARY ......................................................................... 11 3.0 – OFFSITE ANALYSIS ........................................................................................................................... 13 3.1 – UPSTREAM ANALYSIS ..................................................................................................................................... 13 3.2 – DOWNSTREAM ANALYSIS .............................................................................................................................. 13 4.0 – FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN ............................. 15 4.1 – EXISTING SITE HYDROLOGY (PART A) ........................................................................................................... 15 4.2 – DEVELOPED SITE HYDROLOGY (PART B) ...................................................................................................... 15 4.3 – PERFORMANCE STANDARDS (PART C) ......................................................................................................... 16 4.4 – FLOW CONTROL SYSTEM (PART D) ............................................................................................................... 18 4.5 – WATER QUALITY SYSTEM (PART E) ............................................................................................................... 19 5.0 – CONVEYANCE SYSTEM ANALYSIS AND DESIGN .......................................................................... 20 6.0 – SPECIAL REPORTS AND STUDIES ................................................................................................... 20 7.0 – OTHER PERMITS .............................................................................................................................. 20 8.0 – CSWPP ANALYSIS AND DESIGN ..................................................................................................... 20 9.0 – BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT .................. 20 10.0 – OPERATIONS AND MAINTENANCE MANUAL............................................................................ 20 List of Figures Figure 1.1 TIR Worksheet ......................................................................................................................................... 5 Figure 1.2 Site Location .......................................................................................................................................... 10 Figure 3.1 Downstream Flow Path ......................................................................................................................... 13 Figure 4.1 Flow Control Map .................................................................................................................................. 16 Figure 4.2 Water Quality Map ................................................................................................................................. 17 Figure 4.3 Vault Duration Curve ............................................................................................................................. 19 Page | 3 Appendices Appendix A Stormwater Basin Maps Figure 1 – Pre-Developed Basins and Site Areas Figure 2 – Developed Basins and Site Areas Appendix B Flow Control Calculations Appendix C Water Quality Calculations Appendix D TESC Plan Sheets Appendix E Stormwater Plan Sheets Appendix F Bond Quantities Worksheet Appendix G Geotechnical Report Appendix H Operations and Maintenance Manual Page | 4 1.0 – PROJECT OVERVIEW The site address is located at 2200 SW 320th St, Federal Way, in unincorporated King County, parcel numbers 1321039002 and 1321039091. The project proposes to subdivide the existing two parcels into individual, smaller lots for the construction of detached single units. The zoning for this project is RS 5.0. The size of the site is 91,578 SF (2.1 acres). Existing Conditions: The project is located in the Lower Puget Sound Basin. The site is benched, with the south half of the site sitting approximately 15 to 20 feet above the north half of the site. The site is undeveloped with the existing vegetation mostly trees and brushes There are no critical areas within the vicinity of the site. Post-Developed Conditions: The project will clear the entire 2.1 acres of the site, including 0.5 acres of off-site, full-depth disturbance in the right-of-way. The total site after development will be 2.1 acres. See Section 4.0 for a detailed description the drainage basins. The proposed site will be 52% impervious, including roofs, driveways, sidewalks, and roadway. The site will implement an infiltrating stormwater detention facility to the conservation flow control standard, and water quality to the Enhanced Basic standard. Stormwater discharge will be to the existing pubic stormwater drainage system located in SW 320th Street. Page | 5 Figure 1.1 – Technical Information Report (TIR) Worksheet, page 1 Page | 6 Figure 1.1 – Technical Information Report (TIR) Worksheet, page 2 Page | 7 Figure 1.1– Technical Information Report (TIR) Worksheet, page 3 Page | 8 Figure 1.1 – Technical Information Report (TIR) Worksheet, page 4 Page | 9 Figure 1.1 – Technical Information Report (TIR) Worksheet, page 5 Page | 10 Site Location: The site is located in Federal Way in unincorporated King County at the corner of SW 320th Street and 21st Ave SW. See Figure 1.2 below. Figure 1.2 – Site Location Soils: The project site is approximately 2.1 acres and is completely undeveloped and forested. The north and west sides of the site slope from 15% to 45%; while the rest of the site slopes approximately 5% to 10%. The soils consist of medium dense to dense recessional outwash sands and gravels. Native soils may also be classified chiefly as extremely to very gravelly coarse sand with fines contents ranging from 1.7 to 4.1 percent. The native sands and gravels are considered favorable for the infiltration of onsite stormwater. See Appendix G for the geotechnical report. PROJECT SITE Page | 11 2.0 – CONDITIONS AND REQUIREMENTS SUMMARY Stormwater Code and Engineering Standards: The design of the facilities on-site conforms to the King County 2016 Surface Water Manual (KCSWM) and the City of Federal Way Addendum to the 2016 KCSWM. Core Requirements: 1. Discharge at Natural Location: The entirety of the existing sites discharges into the public storm drainage system within the Lower Puget Sound Basin towards Arbor Lake. There are two natural discharge points that converge within 1 mile downstream. All of the site stormwater is proposed to preserve the natural discharge location. 2. Offsite Analysis: A Level 1 Offsite Analysis was conducted. This analysis is detailed in Section 3.0 of this report. 3. Flow Control: The site is located within a conservation flow control area and no downstream problems have been identified. Therefore, the flow control system has been sized and designed for Level 2 Detention. WWHM12 has been used for calculations. Results and a discussion are presented in Section 4.0 of this report. 4. Conveyance System: The majority of proposed site drainage system collects drainage via catch basin inlets through tight lined pipe and into onsite detention/infiltration system and water quality media cartridges. Discharge will then be routed to the public drainage system on 21st Ave SW. 5. Erosion and Sediment Control: A TESC plan will be developed to contain sediment and prevent erosion and will be included in this report upon completion. 6. Maintenance and Operations: An operations and maintenance manual for the drainage facilities will be included in Appendix H of this report upon completion. 7. Financial Liability: The project will provide all King County bonding and/or assignment of savings as required for the development’s construction and warranty periods. 8. Water Quality: The project is required to provide enhanced water quality treatment for all new and replaced pollution generating surfaces. Stormwater treatment will be provided post detention. Page | 12 Special Requirements: 1. Other Adopted Area-Specific Requirements: No other area specific requirements are in place. 2. Flood Hazard Area Delineation: The project is not within a flood hazard area. 3. Flood Protection Facilities: This project is not within a flood hazard area. 4. Source Control: No source control measures are required. 5. Oil Control: The site is primarily a residential site with no proposed commercial space. Therefore, the site is not considered a high-use site and no oil control is required. Page | 13 3.0 – OFFSITE ANALYSIS 3.1 – UPSTREAM ANALYSIS The upstream sides of the site on SW 320th Street and 21st Ave SW are completely contained within the public streets. 3.2 – DOWNSTREAM ANALYSIS A level 1 downstream analysis was conducted. See Figure 3.1 below. Figure 3.1 – Downstream Flow Path Page | 14 The existing site has two separate drainage basins. Drainage on 21st Ave SW and the eastern portion of the site flow to the north, labeled Threshold Discharge Area 1, while the rest of the site, along with SW 320th St flows to the west, which is labeled Threshold Discharge Area 2. The following narrative refers to Figure 1 in Appendix A. Threshold Discharge Area 1 has one discharge point. The drainage from 21st Ave SW is contained within the right-of-way and flows north along the gutter before eventually entering the public storm drainage system through a catch basin inlet. Examining the records from City of Federal Way for the storm drainage, the drainage flows north along 21st Ave SW, and then goes east towards SW Dash point Rd. From there, the downstream route takes the flow generally west for about 0.6 miles and eventually converges with flows from Threshold Discharge Area #2. Threshold Discharge Area 2 has one basic discharge point. SW 320th St and the western portion of the site drain to catch basins in the gutter of that street, which drain west past the site for 0.2 miles and discharge to a ditch and flow for 0.6 miles where it converges with the flows from Threshold Discharge Area 1. From the point where all of the drainage converges downstream, the drainage then flows to the northwest about 0.5 miles towards the Puget Sound. Both downstream flow paths were walked during a site visit, and there was no visual evidence of drainage overtopping catch basins or erosion from the City’s storm system. King County iMap was used to check for flood issues, sensitive areas, basin maps, etc. The site is not located within a FEMA floodplain or any of the DDES designated sensitive areas. The iMap does list a few drainage complaints along the downstream flow path, but they do not appear to be directly related to the public storm drain system that our discharge flows will travel through. Page | 15 4.0 – FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN 4.1 – EXISTING SITE HYDROLOGY (PART A) The existing site hydrology consists of 1.5 acres of pervious surface (forest) and 0.6 acres of impervious surface (building foundation, wood shed, and pavement), totaling 2.1 acres. Discharge paths are described in Section 3.0. The conservation flow control standard requires the existing site to be modeled to historical standards, which is forested. Therefore, the existing site will be modeled as till forest. 4.2 – DEVELOPED SITE HYDROLOGY (PART B) The proposed site will replace the on-site drainage basins, capturing runoff that was sheet-flowing onto adjacent properties and routing it through the detention system. A total of 1.1 acres of impervious surface and 1.0 acres of pervious landscaping will be captured in an infiltrating detention pond (See Figure 2 in Appendix A). This pond then discharges into the public storm drainage system in SW 320th Street. Page | 16 4.3 – PERFORMANCE STANDARDS (PART C) Flow Control Requirements: The flow control standard for the site was determined from the City of Federal Way Flow Control Map. As shown in Figure 4.1 below, the site lies within the conservation flow control area. Target areas include all new and replaced impervious and pervious surfaces that are not fully dispersed. Detention shall match historic site condition for duration between 50% of the 2-yr up to the full 50-yr peak flow, as well as matching the historic 2 year and 10 year peaks. Figure 4.1 – Flow Control Map Flow Control BMP Requirements: The site will have greater than 7,000 SF of land disturbing activity, therefore, will be required to mitigate through Flow Control BMPs. Site Page | 17 Conveyance System Capacity Requirements: The site will have all new piped conveyance system. Per Section 1.2.4.1 of the KCSWM, piped systems must be designed at a minimum to carry the 25-year peak flow, and to ensure that 100-year runoff events do not cause severe flooding or severe erosion problems. Water Quality Treatment Requirements: The site lies within an enhanced basic water quality treatment area, per Figure 4.2 below. Target surfaces include all new and replaced PGIS and PGPS on the proposed site. Figure 4.2 – Water Quality Map Site Page | 18 4.4 – FLOW CONTROL SYSTEM (PART D) The flow control system was designed using WWHM2012 to the conservation flow control standard. Refer to the table below for a summary of each detention system. See Figure 2 in Appendix A for impervious surface calculations and Appendix B for detailed WWHM2012 calculations. Table 4.1 – Detention Pond Summary Contributing Basins Area 1 & Area 2 Overflow Height 5 ft Historic Conditions 2.1 acres Till Forest Orifice 3 H= 4.25 ft D= 0.6 in Modelled Developed Conditions 1.1 acres Impervious 1.0 acres Till Grass Orifice 2 H= 4.00 ft D= 1.34 in System Description 7’W x 50’L x 7’H Side Slopes 3:1 Orifice 1 H= 0.00 ft D= 0.95 in System Volume 7,527 cf Infiltration Rate 4.15 in/hr The conservation flow control standard requires that developed flow durations match the historic flows between 50% of the 2-yeark peak flow up to the full 50-year flow. See Figure 4.3 for the flow duration curve showing compliance with that standard. In addition, the conservation flow control standard requires that peak developed flows do not exceed historical peak flows for the 2-year and 10-year storms. See Table 4.2 below. Table 4.2 – Detention Peak Summary Historic 2-year Peak Flow 0.063 cfs Historic 10-year Peak Flow 0.128 cfs Developed 2-year Peak Flow 0.040 cfs Developed 10-year Peak Flow 0.063 cfs Page | 19 Figure 4.3 – Vault Duration Curve 4.5 – WATER QUALITY SYSTEM (PART E) The project is required to treat all target PGIS and PGPS surfaces to the enhanced basic standard. A stormwater treatment system will be proposed pre-detention. The standard flow rate calculated from WWHM2012 for 1.1 acres of impervious surface and 1.0 acres of pervious landscaping is 0.0989 cfs. Converting this to gpm gives a flow rate of 44.4 gpm. From the Department of Ecology (TAPE) enhanced treatment list, the MWS-Linear Modular Wetland system was sized at 1 gmp per square foot. Per the manufacturer, the MWS-L-4-8 with 50 SF of wetland media surface area should be sufficient size meet the 44.4 gpm of on-site flow. Full water quality calculations will be provided when completed. Page | 20 5.0 – CONVEYANCE SYSTEM ANALYSIS AND DESIGN Pipe Sizing: The proposed stormwater conveyance system will be designed to contain the 100-year storm. 6.0 – SPECIAL REPORTS AND STUDIES Geotechnical Report: Earth Solutions Project No. ES-6375 December 7th, 2018 7.0 – OTHER PERMITS N/A 8.0 – CSWPP ANALYSIS AND DESIGN ESC measures listed in the 2016 KCSWDM will be evaluated for use on the proposed site and will be included in the report upon completion. 9.0 – BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT A bond quantities worksheet will be provided in Appendix F of this report upon completion. 10.0 – OPERATIONS AND MAINTENANCE MANUAL An operations and maintenance manual for the drainage facilities will be provided in Appendix H of this report upon completion. APPENDIX A Stormwater Basin Maps Figure 1 – Pre-developed Basins and Site Areas Figure 2 – Developed Basins and Site Areas TRESHOLD DISCHARGE AREA 1 0.84 AC FOREST TRESHOLD DISCHARGE AREA 2 1.26 AC FOREST 98102-3513BUSH, ROED & HITCHINGS, INC.2009 MINOR AVE. EASTSEATTLE, WashingtonLAND SURVEYORS & CIVIL ENGINEERSFAX# (206) 323-7135(206) 323-41441-800-935-0508PRE-DEVELOPED BASINS & SITE AREAS2200 SW 320TH ST SKYLINE PROPERTIES INC.FEDERAL WAYKING COUNTYWASHINGTONSCALE IN FEET 0 20 1"=20' 20 10 40 SITE AREAS:98102-3513BUSH, ROED & HITCHINGS, INC.2009 MINOR AVE. EASTSEATTLE, WashingtonLAND SURVEYORS & CIVIL ENGINEERSFAX# (206) 323-7135(206) 323-41441-800-935-0508DEVELOPED BASINS & SITE AREAS2200 SW 320TH ST SKYLINE PROPERTIES INC.FEDERAL WAYKING COUNTYWASHINGTONSCALE IN FEET 0 20 1"=20' 20 10 40 APPENDIX B Flow Control Calculations WWHM2012 PROJECT REPORT DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 2 General Model Information Project Name:Infiltrating Pond Site Name: Site Address: City: Report Date:2/25/2019 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2018/10/10 Version:4.2.16 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Mod 2.1 Pervious Total 2.1 Impervious Land Use acre Impervious Total 0 Basin Total 2.1 Element Flows To: Surface Interflow Groundwater DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 1 Pervious Total 1 Impervious Land Use acre SIDEWALKS FLAT 1.1 Impervious Total 1.1 Basin Total 2.1 Element Flows To: Surface Interflow Groundwater Trapezoidal Pond 1 Trapezoidal Pond 1 DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 5 Routing Elements Predeveloped Routing DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 6 Mitigated Routing Trapezoidal Pond 1 Bottom Length:50.00 ft. Bottom Width:7.00 ft. Depth:6 ft. Volume at riser head:0.1728 acre-feet. Infiltration On Infiltration rate:4.15 Infiltration safety factor:1 Wetted surface area On Total Volume Infiltrated (ac-ft.):202.825 Total Volume Through Riser (ac-ft.):51.075 Total Volume Through Facility (ac-ft.):253.901 Percent Infiltrated:79.88 Total Precip Applied to Facility:2.16 Total Evap From Facility:0.401 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:5 ft. Riser Diameter:18 in. Orifice 1 Diameter:0.95 in.Elevation:0 ft. Orifice 2 Diameter:1.34 in.Elevation:4 ft. Orifice 3 Diameter:0.6 in.Elevation:4.25 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.008 0.000 0.000 0.000 0.0667 0.008 0.000 0.006 0.035 0.1333 0.009 0.001 0.008 0.038 0.2000 0.009 0.001 0.011 0.040 0.2667 0.010 0.002 0.012 0.042 0.3333 0.010 0.003 0.014 0.045 0.4000 0.011 0.003 0.015 0.047 0.4667 0.011 0.004 0.016 0.049 0.5333 0.012 0.005 0.017 0.052 0.6000 0.013 0.006 0.019 0.054 0.6667 0.013 0.007 0.020 0.057 0.7333 0.014 0.008 0.021 0.059 0.8000 0.014 0.009 0.021 0.062 0.8667 0.015 0.010 0.022 0.064 0.9333 0.016 0.011 0.023 0.067 1.0000 0.016 0.012 0.024 0.069 1.0667 0.017 0.013 0.025 0.072 1.1333 0.018 0.014 0.026 0.075 1.2000 0.018 0.015 0.026 0.078 1.2667 0.019 0.017 0.027 0.080 1.3333 0.020 0.018 0.028 0.083 1.4000 0.020 0.019 0.029 0.086 1.4667 0.021 0.021 0.029 0.089 DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 7 1.5333 0.022 0.022 0.030 0.092 1.6000 0.022 0.024 0.031 0.095 1.6667 0.023 0.025 0.031 0.098 1.7333 0.024 0.027 0.032 0.101 1.8000 0.024 0.028 0.032 0.104 1.8667 0.025 0.030 0.033 0.107 1.9333 0.026 0.032 0.034 0.110 2.0000 0.027 0.034 0.034 0.113 2.0667 0.027 0.035 0.035 0.116 2.1333 0.028 0.037 0.035 0.119 2.2000 0.029 0.039 0.036 0.122 2.2667 0.030 0.041 0.036 0.125 2.3333 0.030 0.043 0.037 0.129 2.4000 0.031 0.045 0.037 0.132 2.4667 0.032 0.047 0.038 0.135 2.5333 0.033 0.050 0.039 0.139 2.6000 0.034 0.052 0.039 0.142 2.6667 0.034 0.054 0.040 0.145 2.7333 0.035 0.056 0.040 0.149 2.8000 0.036 0.059 0.041 0.152 2.8667 0.037 0.061 0.041 0.156 2.9333 0.038 0.064 0.041 0.159 3.0000 0.039 0.066 0.042 0.163 3.0667 0.039 0.069 0.042 0.166 3.1333 0.040 0.072 0.043 0.170 3.2000 0.041 0.074 0.043 0.174 3.2667 0.042 0.077 0.044 0.177 3.3333 0.043 0.080 0.044 0.181 3.4000 0.044 0.083 0.045 0.185 3.4667 0.045 0.086 0.045 0.189 3.5333 0.046 0.089 0.046 0.192 3.6000 0.047 0.092 0.046 0.196 3.6667 0.047 0.095 0.046 0.200 3.7333 0.048 0.099 0.047 0.204 3.8000 0.049 0.102 0.047 0.208 3.8667 0.050 0.105 0.048 0.212 3.9333 0.051 0.109 0.048 0.216 4.0000 0.052 0.112 0.049 0.220 4.0667 0.053 0.116 0.062 0.224 4.1333 0.054 0.119 0.067 0.228 4.2000 0.055 0.123 0.072 0.232 4.2667 0.056 0.127 0.077 0.236 4.3333 0.057 0.131 0.081 0.240 4.4000 0.058 0.134 0.086 0.245 4.4667 0.059 0.138 0.089 0.249 4.5333 0.060 0.142 0.092 0.253 4.6000 0.061 0.146 0.096 0.257 4.6667 0.062 0.151 0.099 0.262 4.7333 0.063 0.155 0.101 0.266 4.8000 0.064 0.159 0.104 0.271 4.8667 0.065 0.163 0.107 0.275 4.9333 0.066 0.168 0.109 0.279 5.0000 0.068 0.172 0.112 0.284 5.0667 0.069 0.177 0.388 0.288 5.1333 0.070 0.182 0.888 0.293 5.2000 0.071 0.186 1.523 0.298 5.2667 0.072 0.191 2.244 0.302 5.3333 0.073 0.196 3.005 0.307 DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 8 5.4000 0.074 0.201 3.757 0.311 5.4667 0.075 0.206 4.453 0.316 5.5333 0.076 0.211 5.053 0.321 5.6000 0.077 0.216 5.532 0.326 5.6667 0.079 0.221 5.887 0.330 5.7333 0.080 0.227 6.148 0.335 5.8000 0.081 0.232 6.475 0.340 5.8667 0.082 0.237 6.735 0.345 5.9333 0.083 0.243 6.986 0.350 6.0000 0.084 0.249 7.228 0.355 6.0667 0.086 0.254 7.462 0.360 DRAFTInfiltrating Pond 2/25/2019 1:19:57 PM Page 9 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:2.1 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:1 Total Impervious Area:1.1 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.062528 5 year 0.102458 10 year 0.128131 25 year 0.158672 50 year 0.179826 100 year 0.199585 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.039674 5 year 0.05298 10 year 0.063209 25 year 0.077847 50 year 0.090073 100 year 0.103498 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.072 0.042 1950 0.085 0.041 1951 0.137 0.044 1952 0.043 0.034 1953 0.035 0.034 1954 0.053 0.035 1955 0.085 0.044 1956 0.068 0.038 1957 0.055 0.042 1958 0.061 0.039 DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 10 1959 0.053 0.035 1960 0.094 0.043 1961 0.052 0.035 1962 0.032 0.031 1963 0.044 0.033 1964 0.063 0.036 1965 0.042 0.035 1966 0.040 0.035 1967 0.096 0.043 1968 0.054 0.037 1969 0.053 0.038 1970 0.042 0.037 1971 0.048 0.036 1972 0.104 0.044 1973 0.046 0.036 1974 0.051 0.034 1975 0.071 0.043 1976 0.051 0.036 1977 0.007 0.033 1978 0.043 0.041 1979 0.026 0.034 1980 0.122 0.041 1981 0.038 0.038 1982 0.079 0.047 1983 0.068 0.040 1984 0.041 0.034 1985 0.024 0.037 1986 0.107 0.046 1987 0.095 0.046 1988 0.037 0.033 1989 0.025 0.031 1990 0.226 0.099 1991 0.120 0.065 1992 0.049 0.038 1993 0.048 0.033 1994 0.016 0.030 1995 0.069 0.038 1996 0.159 0.046 1997 0.122 0.047 1998 0.030 0.036 1999 0.134 0.043 2000 0.048 0.040 2001 0.009 0.033 2002 0.055 0.046 2003 0.083 0.035 2004 0.088 0.195 2005 0.065 0.043 2006 0.074 0.039 2007 0.171 0.087 2008 0.209 0.108 2009 0.097 0.045 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.2264 0.1948 2 0.2086 0.1085 3 0.1711 0.0992 DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 11 4 0.1586 0.0866 5 0.1366 0.0651 6 0.1342 0.0472 7 0.1224 0.0468 8 0.1221 0.0460 9 0.1201 0.0460 10 0.1071 0.0458 11 0.1037 0.0456 12 0.0973 0.0445 13 0.0960 0.0445 14 0.0946 0.0443 15 0.0943 0.0437 16 0.0882 0.0432 17 0.0854 0.0431 18 0.0850 0.0430 19 0.0825 0.0428 20 0.0792 0.0426 21 0.0736 0.0424 22 0.0720 0.0417 23 0.0709 0.0414 24 0.0686 0.0411 25 0.0685 0.0406 26 0.0677 0.0403 27 0.0654 0.0399 28 0.0628 0.0386 29 0.0614 0.0386 30 0.0553 0.0384 31 0.0552 0.0382 32 0.0540 0.0382 33 0.0532 0.0377 34 0.0526 0.0376 35 0.0526 0.0374 36 0.0518 0.0370 37 0.0510 0.0368 38 0.0507 0.0363 39 0.0490 0.0361 40 0.0479 0.0359 41 0.0477 0.0357 42 0.0477 0.0357 43 0.0460 0.0354 44 0.0443 0.0350 45 0.0429 0.0349 46 0.0428 0.0348 47 0.0422 0.0346 48 0.0417 0.0346 49 0.0408 0.0343 50 0.0401 0.0342 51 0.0383 0.0340 52 0.0373 0.0340 53 0.0346 0.0338 54 0.0323 0.0331 55 0.0299 0.0331 56 0.0259 0.0328 57 0.0247 0.0327 58 0.0242 0.0326 59 0.0161 0.0310 60 0.0086 0.0309 61 0.0074 0.0299 DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 12 DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 13 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.0313 17079 5813 34 Pass 0.0328 15488 4494 29 Pass 0.0343 14070 3448 24 Pass 0.0358 12799 2733 21 Pass 0.0373 11569 2088 18 Pass 0.0388 10519 1558 14 Pass 0.0403 9565 1137 11 Pass 0.0418 8752 790 9 Pass 0.0433 8036 522 6 Pass 0.0448 7347 352 4 Pass 0.0463 6731 227 3 Pass 0.0478 6188 172 2 Pass 0.0493 5726 137 2 Pass 0.0508 5309 132 2 Pass 0.0523 4924 129 2 Pass 0.0538 4569 127 2 Pass 0.0553 4235 125 2 Pass 0.0568 3951 124 3 Pass 0.0583 3643 122 3 Pass 0.0598 3388 117 3 Pass 0.0613 3133 116 3 Pass 0.0628 2915 112 3 Pass 0.0643 2706 109 4 Pass 0.0658 2490 106 4 Pass 0.0673 2314 103 4 Pass 0.0688 2136 101 4 Pass 0.0703 1972 100 5 Pass 0.0718 1822 97 5 Pass 0.0733 1702 96 5 Pass 0.0748 1577 92 5 Pass 0.0763 1442 92 6 Pass 0.0778 1325 89 6 Pass 0.0793 1232 86 6 Pass 0.0808 1147 85 7 Pass 0.0823 1083 81 7 Pass 0.0838 1020 79 7 Pass 0.0853 947 75 7 Pass 0.0868 886 65 7 Pass 0.0883 824 63 7 Pass 0.0898 760 61 8 Pass 0.0913 725 58 8 Pass 0.0928 674 54 8 Pass 0.0943 623 49 7 Pass 0.0958 589 48 8 Pass 0.0973 549 43 7 Pass 0.0988 506 42 8 Pass 0.1003 472 37 7 Pass 0.1018 428 35 8 Pass 0.1033 389 33 8 Pass 0.1048 357 26 7 Pass 0.1063 329 21 6 Pass 0.1078 298 17 5 Pass 0.1093 272 12 4 Pass DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 14 0.1108 242 10 4 Pass 0.1123 219 8 3 Pass 0.1138 199 8 4 Pass 0.1153 176 7 3 Pass 0.1168 153 7 4 Pass 0.1183 130 7 5 Pass 0.1198 119 7 5 Pass 0.1213 104 7 6 Pass 0.1228 95 7 7 Pass 0.1243 83 7 8 Pass 0.1258 74 7 9 Pass 0.1273 69 7 10 Pass 0.1288 61 7 11 Pass 0.1303 53 7 13 Pass 0.1318 46 6 13 Pass 0.1333 39 6 15 Pass 0.1348 29 6 20 Pass 0.1363 25 6 24 Pass 0.1378 22 6 27 Pass 0.1393 20 6 30 Pass 0.1408 17 5 29 Pass 0.1423 14 5 35 Pass 0.1438 12 5 41 Pass 0.1453 8 5 62 Pass 0.1468 7 5 71 Pass 0.1483 7 5 71 Pass 0.1498 7 5 71 Pass 0.1513 6 5 83 Pass 0.1528 6 5 83 Pass 0.1543 6 5 83 Pass 0.1558 6 5 83 Pass 0.1573 6 5 83 Pass 0.1588 5 5 100 Pass 0.1603 5 5 100 Pass 0.1618 5 5 100 Pass 0.1633 5 4 80 Pass 0.1648 5 4 80 Pass 0.1663 5 3 60 Pass 0.1678 5 3 60 Pass 0.1693 4 3 75 Pass 0.1708 4 3 75 Pass 0.1723 3 3 100 Pass 0.1738 3 3 100 Pass 0.1753 3 3 100 Pass 0.1768 3 3 100 Pass 0.1783 3 2 66 Pass 0.1798 3 1 33 Pass DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 15 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. DRAFTInfiltrating Pond 2/25/2019 1:20:46 PM Page 16 LID Report DRAFTInfiltrating Pond 2/25/2019 1:21:42 PM Page 17 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. DRAFTInfiltrating Pond 2/25/2019 1:21:42 PM Page 18 Appendix Predeveloped Schematic DRAFTInfiltrating Pond 2/25/2019 1:21:44 PM Page 19 Mitigated Schematic DRAFTInfiltrating Pond 2/25/2019 1:21:46 PM Page 20 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Infiltrating Pond.wdm MESSU 25 PreInfiltrating Pond.MES 27 PreInfiltrating Pond.L61 28 PreInfiltrating Pond.L62 30 POCInfiltrating Pond1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 11 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 11 C, Forest, 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 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 END PRINT-INFO DRAFTInfiltrating Pond 2/25/2019 1:21:46 PM Page 21 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 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 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 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 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 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 <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 DRAFTInfiltrating Pond 2/25/2019 1:21:46 PM Page 22 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 11 2.1 COPY 501 12 PERLND 11 2.1 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 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 DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 23 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 DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 24 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Infiltrating Pond.wdm MESSU 25 MitInfiltrating Pond.MES 27 MitInfiltrating Pond.L61 28 MitInfiltrating Pond.L62 30 POCInfiltrating Pond1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 IMPLND 8 RCHRES 1 COPY 1 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Trapezoidal Pond 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 16 C, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 25 16 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 16 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 16 0 4.5 0.03 400 0.05 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 16 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 16 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 8 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 8 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 8 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 26 # - # ***PETMAX PETMIN 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 16 1 RCHRES 1 2 PERLND 16 1 RCHRES 1 3 IMPLND 8 1.1 RCHRES 1 5 ******Routing****** PERLND 16 1 COPY 1 12 IMPLND 8 1.1 COPY 1 15 PERLND 16 1 COPY 1 13 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 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-007 2 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 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 *** <------><--------><--------><--------><--------><--------><--------> *** DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 27 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 0.008035 0.000000 0.000000 0.000000 0.066667 0.008562 0.000553 0.006324 0.035828 0.133333 0.009096 0.001142 0.008943 0.038065 0.200000 0.009638 0.001766 0.010953 0.040332 0.266667 0.010187 0.002427 0.012647 0.042630 0.333333 0.010744 0.003125 0.014140 0.044958 0.400000 0.011308 0.003860 0.015489 0.047318 0.466667 0.011879 0.004633 0.016731 0.049708 0.533333 0.012457 0.005444 0.017886 0.052129 0.600000 0.013043 0.006294 0.018971 0.054580 0.666667 0.013636 0.007183 0.019997 0.057063 0.733333 0.014237 0.008112 0.020973 0.059576 0.800000 0.014845 0.009082 0.021905 0.062119 0.866667 0.015460 0.010092 0.022800 0.064694 0.933333 0.016083 0.011143 0.023661 0.067299 1.000000 0.016713 0.012237 0.024491 0.069935 1.066667 0.017350 0.013372 0.025294 0.072602 1.133333 0.017994 0.014550 0.026073 0.075299 1.200000 0.018646 0.015772 0.026829 0.078028 1.266667 0.019306 0.017037 0.027564 0.080787 1.333333 0.019972 0.018346 0.028280 0.083576 1.400000 0.020646 0.019700 0.028978 0.086397 1.466667 0.021328 0.021099 0.029660 0.089248 1.533333 0.022017 0.022544 0.030327 0.092130 1.600000 0.022713 0.024035 0.030979 0.095043 1.666667 0.023416 0.025572 0.031618 0.097986 1.733333 0.024127 0.027157 0.032244 0.100960 1.800000 0.024845 0.028790 0.032858 0.103965 1.866667 0.025570 0.030470 0.033461 0.107001 1.933333 0.026303 0.032199 0.034053 0.110067 2.000000 0.027043 0.033977 0.034635 0.113164 2.066667 0.027791 0.035805 0.035208 0.116292 2.133333 0.028545 0.037683 0.035771 0.119451 2.200000 0.029308 0.039611 0.036326 0.122640 2.266667 0.030077 0.041591 0.036872 0.125860 2.333333 0.030854 0.043622 0.037411 0.129111 2.400000 0.031638 0.045705 0.037941 0.132393 2.466667 0.032430 0.047841 0.038465 0.135705 2.533333 0.033229 0.050029 0.038981 0.139048 2.600000 0.034035 0.052271 0.039490 0.142422 2.666667 0.034848 0.054567 0.039994 0.145826 2.733333 0.035669 0.056918 0.040490 0.149262 2.800000 0.036498 0.059324 0.040981 0.152728 2.866667 0.037333 0.061785 0.041466 0.156224 2.933333 0.038176 0.064302 0.041946 0.159752 3.000000 0.039027 0.066875 0.042420 0.163310 3.066667 0.039884 0.069505 0.042888 0.166899 3.133333 0.040749 0.072193 0.043352 0.170519 3.200000 0.041622 0.074939 0.043811 0.174169 3.266667 0.042501 0.077743 0.044265 0.177851 3.333333 0.043388 0.080606 0.044714 0.181563 3.400000 0.044283 0.083528 0.045159 0.185305 DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 28 3.466667 0.045185 0.086511 0.045600 0.189079 3.533333 0.046094 0.089553 0.046036 0.192883 3.600000 0.047010 0.092657 0.046468 0.196718 3.666667 0.047934 0.095822 0.046897 0.200583 3.733333 0.048865 0.099048 0.047321 0.204480 3.800000 0.049803 0.102337 0.047742 0.208407 3.866667 0.050749 0.105689 0.048159 0.212365 3.933333 0.051702 0.109104 0.048572 0.216353 4.000000 0.052663 0.112583 0.048982 0.220373 4.066667 0.053631 0.116126 0.061970 0.224423 4.133333 0.054606 0.119734 0.067584 0.228504 4.200000 0.055589 0.123407 0.071983 0.232615 4.266667 0.056579 0.127146 0.077012 0.236758 4.333333 0.057576 0.130951 0.081935 0.240931 4.400000 0.058580 0.134823 0.085974 0.245134 4.466667 0.059592 0.138762 0.089595 0.249369 4.533333 0.060612 0.142769 0.092930 0.253634 4.600000 0.061638 0.146844 0.096050 0.257930 4.666667 0.062672 0.150987 0.098998 0.262257 4.733333 0.063713 0.155200 0.101802 0.266614 4.800000 0.064762 0.159483 0.104485 0.271003 4.866667 0.065818 0.163836 0.107062 0.275422 4.933333 0.066882 0.168259 0.109547 0.279871 5.000000 0.067952 0.172753 0.111951 0.284352 5.066667 0.069030 0.177319 0.387976 0.288863 5.133333 0.070116 0.181958 0.888009 0.293405 5.200000 0.071208 0.186668 1.523212 0.297978 5.266667 0.072309 0.191452 2.244719 0.302581 5.333333 0.073416 0.196310 3.005512 0.307215 5.400000 0.074531 0.201241 3.757244 0.311880 5.466667 0.075653 0.206247 4.453075 0.316576 5.533333 0.076782 0.211329 5.053212 0.321302 5.600000 0.077919 0.216485 5.532163 0.326059 5.666667 0.079063 0.221718 5.887328 0.330847 5.733333 0.080215 0.227027 6.148682 0.335666 5.800000 0.081374 0.232414 6.475027 0.340515 5.866667 0.082540 0.237877 6.735644 0.345395 5.933333 0.083713 0.243419 6.986454 0.350306 6.000000 0.084894 0.249039 7.228492 0.355248 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 WDM 2 PREC ENGL 1 RCHRES 1 EXTNL PREC WDM 1 EVAP ENGL 0.76 RCHRES 1 EXTNL POTEV END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** 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 DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 29 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 DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 30 Predeveloped HSPF Message File DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 31 Mitigated HSPF Message File DRAFTInfiltrating Pond 2/25/2019 1:21:47 PM Page 32 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. 2005-2019; 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 APPENDIX C Water Quality Calculations Will be provided upon completion APPENDIX D TESC Plan Sheets Will be provided upon completion APPENDIX E Stormwater Plan Sheets See Preliminary Plat for storm drainage details APPENDIX F Bond Quantities Worksheet Will be provided upon completion APPENDIX G Geotechnical Report EarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineering Construction Observation/Testing Environmental Services 1805 -136th Place N.E.,Suite 201 Bellevue,WA 98005 (425)449-4704 Fax (425)449-4711 www.earthsolutionsnw.com GEOTECHNICAL ENGINEERING STUDY PROPOSED RESIDENTIAL DEVELOPMENT SOUTHWEST OF 21 AVENUE SOUTHWEST AND SOUTHWEST 320 STREET FEDERAL WAY,WASHINGTON ES-6375 ST TH Drwn. Checked Date Date Proj.No. Plate Earth Solutions NWLLC Geotechnical Engineering,Construction EarthSolutionsNWLLC EarthSolutions NW LLC Observation/Testing and Environmental Ser vices Vicinity Map S.W.320th Street Plat Federal Way,Washington MRS KTK 11/12/2018 Nov.2018 6375 1 NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. Reference: King County,Washington Map 744 By The Thomas Guide Rand McNally 32nd Edition SITE Plate Proj.No. Date Checked By Drwn.ByEarthSolutionsNWLLCGeotechnicalEngineering,ConstructionObservation/TestingandEnvironmentalServicesEarthSolutionsNWLLCEarthSolutionsNWLLCMRS KTK 12/05/2018 6375 2TestPitLocationPlan S.W.320thStreetPlatFederalWay,WashingtonNORTH 0 3 0 6 0 1 2 0 Sc ale in Feet1"=6 0 ' NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. NOTE:The graphics shown on this plate are not intended for design purposes or precise scale measurements,but only to illustrate the approximate test locations relative to the approximate locations of existing and /or proposed site features.The information illustrated is largely based on data provided by the client at the time of our study.ESNW cannot be responsible for subsequent design changes or interpretation of the data by others. LEGEND Approximate Location of ESNW Test Pit,Proj.No. ES-6375,Oct.2018 Subject Site Existing Building TP-1 TP-2 TP-3 TP-4 TP-5 TP-6 TP-1 Remnant Concrete Foundation Dilapidated Shed S.W. 320TH STREET 21ST AVENUE S.W.350340 330320 350 340 330 320 Drwn. Checked Date Date Proj.No. Plate Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineer ing,C onstr uction Observation/Testing and Environmental Services Retaining Wall Drainage Detail S.W.320th Street Plat Federal Way,Washington MRS KTK 11/12/2018 Nov.2018 6375 3 NOTES: Free-draining Backfill should consist of soil having less than 5 percent fines. Percent passing No.4 sieve should be 25 to 75 percent. Sheet Drain may be feasible in lieu of Free-draining Backfill,per ESNW recommendations. Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1-inch Drain Rock. LEGEND: Free-draining Structural Backfill 1-inch Drain Rock 18"Min. Structural Fill Perforated Rigid Drain Pipe (Surround in Drain Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAWING Drwn. Checked Date Date Proj.No. Plate Earth Solutions NWLLC Geotechnical Engineering,Construction Observation/Testing and Environmental Services EarthSolutionsNWLLC EarthSolutions NW LLC Footing Drain Detail S.W.320th Street Plat Federal Way,Washington MRS KTK 11/12/2018 Nov.2018 6375 4 Slope Perforated Rigid Drain Pipe (Surround in Drain Rock) 18"Min. NOTES: Do NOT tie roof downspouts to Footing Drain. Surface Seal to consist of 12"of less permeable,suitable soil.Slope away from building. LEGEND: Surface Seal:native soil or other low-permeability material. 1-inch Drain Rock SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAW ING APPENDIX H Operations and Maintenance Manual Will be provided upon completion