Loading...
HomeMy WebLinkAboutStudies APPLICANT 8/27/2021 (2)Stormwater Management Plan and Drainage Study HIGINEERING= Since 19T civil - transportation structural - geotechnical SURVEYING www.BranchEngineering.com Deadmond Ferry Project, LLC Branch Engineering Project #20-517 For Mike O'Connell Deadmond Ferry Project, LLC 287 Deadmond Ferry Rd Springfield, OR 97477 (541)377-7670 CC: Richard M. Satre The Satre Group 375 West 4" Avenue, Ste 201 Eugene, Or 97401 PROF GIN #7923213E ,#79232PE Date: 021.0 .3 by a a gally Sig Date: 2021.07.3009:52:5 -e EXPIRES: 12/31/22 JULY 30, 2021 Contents Page No. 1.0 Introduction...............................................................................................................1 2.0 Existing conditions.................................................................................................1 2.1 Topography & Existing Drainage 1 2.2 Soils 2 2.3 Infiltration Testing 2 3.0 Proposed Development 4.0 Stormwater Management.....................................................................................3 4.1 Stormwater Summary 3 4.2 Stormwater Analysis 3 5.0 Stormwater Compliance........................................................................................4 5.1 Water Quality Treatment 4 5.2 Flow Control 5 6.0 Conclusion..................................................................................................................5 Appendices Description Appendix A HydroCAD Analysis Existing Site Conditions Analysis Post -Developed Conditions Analysis Appendix B Infiltration Test Summary Deadmond Ferry Project (20-517) July 30, 2021 1.0 INTRODUCTION This Stormwater Management Plan (SWMP) has been prepared for the Deadmond Ferry Development at the current residence of 287 Deadmond Ferry Road in Springfield, also identified as Tax Map 17-03-15-40, "Lax Lot 1800. The new development will consist of the existing single- family home with possible additions and three multi -unit buildings. The stormwater from the buildings will be directed to soakage trenches. The paved parking areas and drive aisles will be directed to vegetated rain gardens located on the west side of the site for treatment and detention, then directed into soakage trenches for further detention and dissipation. The purpose of this report is to document the treatment and detention design and establish maintenance requirements. The project falls within the City of Springfield and will therefore need to meet water quality and flow control requirements set by the City. The current residence has one conveyance system for stormwater, draining to a weephole in the curb of Deadmond Ferry Road but does not concert to any city stormwater infrastructure. For that reason, all of the runoff will have to be detained on- site through the 10 -year storm event with the use of various rain gardens and soakage trenches. This report will display conformance to the City of Springfield requirements for water quality as well as display the amount of retention intended to reduce the peak discharge rates from the post - developed site to match the pre -developed condition. 2.0 EXISTING CONDITIONS 2.1 TOPOGRAPHY & EXISTING DRAINAGE The existing site is quite flat with elevations ranging between 438 & 439 feet. The subject site is approximately 0.85 acres in size andlocated approximately 1050 feet east of the intersection of Game Farm Road and Deadmond Ferry Road. The site is primarily grassland with some trees in the north and western portions of the site. A single-family residential structure currently occupies the north portion of the site but will be modified with the new development and partitioned onto its own parcel. The current drainage pattern is undetermined due to the relatively flat site with no general sloping pattern. The new development will need to include infiltration facilities to reflect the existing conditions because offsite drainage is minimal. There are no stormwater connections into public piped systems and no approval to connect into said systems due to the nature of the concrete roadway of Deadmond Ferry Road. Deadmond Ferry Project (20-517) July 30, 2021 Table 1: Existing Basin Summary 2.2 SOILS According to the Natural Conservation Service Website mapping services, the existing soils at the site are Malabon silty clay loam (NRCS Soil #75). This soil is in the Hydrologic Group C, where water transmission through the soil is somewhat restricted. Appendix B includes the NRCS Web Soil Survey data. 2.3 INFILTRATION TESTING Three encased falling head infiltration tests were performed on January 4, 2021. Infiltration tests were conductedwith 6 -inch diameter pipes set and sealed within soil borings. Infiltration test locations are shown on the attached Figure -1. The recorded field test measurements are provided in Appendix A. No factor of safety has been applied to the measured rates below. Based on the testing results, on-site infiltration of stormwater from impervious surfaces appears to be feasible. Table 2: Results from on-site infiltration testing Test Location Test Depth [Inches) Area IT -I 2 -Year Runoff 10 -Year Runoff Existing Building 3.5 Peak Runoff Peak Runoff Basin SUM ID Summary Grass/ Roof Impervious (ft z ) Flow Volume Flow Volume Landscape (CN -98) (CN=98) (cfs) (Acre -ft) (cfs) (Acreft) (CN=75) Existing EN North 2,950 1,395 950 5,295 0.05 0.019 0.08 0.028 Basin Existing ES South 29,650 0 480 30,130 0.16 0.067 0.29 0.109 Basin 2.2 SOILS According to the Natural Conservation Service Website mapping services, the existing soils at the site are Malabon silty clay loam (NRCS Soil #75). This soil is in the Hydrologic Group C, where water transmission through the soil is somewhat restricted. Appendix B includes the NRCS Web Soil Survey data. 2.3 INFILTRATION TESTING Three encased falling head infiltration tests were performed on January 4, 2021. Infiltration tests were conductedwith 6 -inch diameter pipes set and sealed within soil borings. Infiltration test locations are shown on the attached Figure -1. The recorded field test measurements are provided in Appendix A. No factor of safety has been applied to the measured rates below. Based on the testing results, on-site infiltration of stormwater from impervious surfaces appears to be feasible. Table 2: Results from on-site infiltration testing Test Location Test Depth [Inches) Measured Hydraulic Conducltvitgk anc/hr) IT -I 4.3 2.5 IT -2 43 3.5 From the table above, it can be seen that the infiltration tests that were conducted provided adequate percolation rates for a majority of the site. See Appendix B for additional summary of the infiltration tests. 3.0 PROPOSED DEVELOPMENT the proposed development consists of new mutti-unit housing, associated parking, walkways, and utility improvements. There is also some frontage improvements which will consist of installing a new driveway with new standard sidewalks in a more convenient location for design purposes. Branch Engineering, Inc. Deadmond Ferry Project (20-517) July 30, 2021 Stormwater treatment will meet City of Springfield requirements which have adopted portions of Eugene's Stormwater Management Manual. 4.0 STORMWATER MANAGEMENT 4.1 STORNIWATER SUM: IARY Stormwater runoff will be managed by two rain gardens located across the western portion of the site and four soakage trenches located throughout the site. These facilities will be sized to increase storage capacity while runoff infiltrates into the soil to match or reduce pre -developed runoff rates. According to the City of Eugene Stormwater Management Manual, Rain Cardens are vegetated "infiltration basins with a flat bottom and shallow landscaped depressions used to collect and hold siormwater runoff, allowing pollutants to settle and filter out as water percolates through the planter soils before infiltration into the ground below or piped to its downstream destination." The rain gardens will treat all of the runoff from the pavement. Soakage trenches are "flood control devices injecting stormwater runoff into the ground recharging groundwater. Soakage trenches are linear excavations tined and backfilled with drain rock and gravel retaining runoff volumes as it infiltrates into the surrounding soils:' The soakage trenches will detain all of the runoff as it infiltrates into the soil over time. During large storm events, the soakage trenches become saturated then will backup and runoff will be released into the street via the weephole overflow. The soakage trenches will be considered Underground Injection Control devices (UIC) which will be registered with the DEQ and meet all DEQ requirements. 4.2 STORAIWATER ANALYSIS All stormwater calculations were determined using HydroCAD 10.00 modeling software. This program utilizes the Santa Barbara Unit Hydrograph hydraulic modeling method. All results of the analysis are included in Appendix A. 24 -Hour Rainfall depths are based on City of Springfield Engineering Design Standards & Procedures Manual, Chapter 4. The proposed basin areas were split into numerous sub basins based on their various facility destinations. The routing diagram can be found in Appendix A. The following table displays some of the characteristics and results of the infiltration facilities during the two primary design storm events (Water Quality, & 10 Year Storm). Branch Engineering, Inc. Deadmond Ferry Project (20-517) July 30, 2021 Table 3: Infiltration Facility Properties *The storage of the ditch inlet in the HydroCAD Model is included so that the elevation in the facility can rise and balance with the level in the rain garden above if necessary. The rain gardens utilize an infiltration rate of 2.0 in/hr. Soakage trenches were designed with an infiltration rate of 1.5 in/hr based on field test results. The HydroCAll analysis outputs can be found in Appendix A and will be discussed in more detail in the following sections. 5.0 STORMWATER COMPLIANCE 5.1 WATER QUALITY TREATMENT The stormwater facilities described above were designed to meet City of Springfield Stormwater Management requirements per section 3.02,3.03, 4.16 and 4.17. This section will briefly confirm that the treatment mechanisms are in fact meeting those requirements. From the hydraulic analysis in Appendix A and the notes from the previous section, the primary indicator for water quality compliance for the rain garden is to make sure the water quality storm infiltrates through the filtering media and stays below the overflow. Since the water level in the rain gardens stay below the overflow elevations for each facility during the water quality event, those facilities meet the water quality requirements. Roofs are not required to be treated prior to Branch Engineering, Inc. 4 Water Duality Storm Facility Contributing Elevation Elevation Overflow Event 10 -Year Stoon Event Peak Volume Volume ID Basins (modeled) annealed) Elevation Depth Depth Discharge Infiltrated Released Rate (chs) (acre-feet) (acre-feet) 51, B2, B3, B4, P1 P2, STI ST2, 434.00 437.00 438.30 434.00 438.37 0.01 0.026 0.031 ST3,ST4 RG1, RG2 ST2 B2 434.00 437.00 436.30 434.00 436.97 0.13 0.031 0.069 ST3 B3 434.00 437.00 43] 00 434.00 435.65 0.02 0.034 0.034 RG1 P1 436.50 438.50 438.25 436.70 438.38 0.07 oeo 0.055 RG2 P2 436.50 438.50 438.25 436,79 438.34 0.18 0.00 0.067 B1,B2,B3.P ST4 1,P2, ST2, 434.0) 437.00 436.70 434.01 435.67 0.06 0.169 0.169 ST3, RG1.RG2 *The storage of the ditch inlet in the HydroCAD Model is included so that the elevation in the facility can rise and balance with the level in the rain garden above if necessary. The rain gardens utilize an infiltration rate of 2.0 in/hr. Soakage trenches were designed with an infiltration rate of 1.5 in/hr based on field test results. The HydroCAll analysis outputs can be found in Appendix A and will be discussed in more detail in the following sections. 5.0 STORMWATER COMPLIANCE 5.1 WATER QUALITY TREATMENT The stormwater facilities described above were designed to meet City of Springfield Stormwater Management requirements per section 3.02,3.03, 4.16 and 4.17. This section will briefly confirm that the treatment mechanisms are in fact meeting those requirements. From the hydraulic analysis in Appendix A and the notes from the previous section, the primary indicator for water quality compliance for the rain garden is to make sure the water quality storm infiltrates through the filtering media and stays below the overflow. Since the water level in the rain gardens stay below the overflow elevations for each facility during the water quality event, those facilities meet the water quality requirements. Roofs are not required to be treated prior to Branch Engineering, Inc. 4 Deadmond Ferry ProjeC (20-517) July 30, 2021 tIICs, however, they are installed with settling basins to avoid sediment being collected in the soakage trenches. 5.2 FLOW CONTROL In order to meet pre -developed runoff rates, which are minimal for this site due to the existing topographic grades, the overflow of each facility was designed to connect to each other to add capacity while runoff infiltrates into the ground. The soakage trench facilities were modeled to infiltrate into the soil at 1.5 inches/hour based on infiltration test results with a factor of safety of 2 applied. During most storms, there is little to no release from the site, despite the pre -developed site having some runoff draining to downspouts releasing runoff into weep holes on Deadmond Ferry Road. However, during the 25 -year stonn, the HydroCAD model shows the existing runoff from the 0.85 - acre development has a peak rate overflow of 0.02 cfs toward the street, which is still well below the pre -developed release rate of 0.08 cfs. 6.0 CONCLUSION The stormwater system for the Deadmond Ferry Project has been designed in accordance with the City of Springfield requirements for water quality and detention by directing all impervious areas to infiltration facilities for treatment and detention. Branch Engineering, Inc. Deadmord Ferry Project (20-517) July 30, 2021 APPENDIX A HydroCAD Analysis Existing Site Analysis Post -Developed Analysis Existing Basin Subcat Reach A L Existing Basin 20-517 SiteRev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by Microsoft Printed 2/19/2021 HydroCAD®10 00-16 s/n 09344 @2015 HydmCAD Software Solutions LLC Paae 2 Summary for Subcatchment EN: Existing Basin Runoff = 0.08 cfs @ 8.01 hrs, Volume= 0.028 af, Depth= 2.73" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) ON Description * 1,395 98 Roof to Downspout * 950 98 Driveway * 2,950 75 Landscape 5,295 85 Weighted Average 2,950 55.71 % Pervious Area 2,345 Slope Velocity Capacity Description 44.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment ES: Existing Basin Runoff = 0.29 cfs @ 8.03 hrs, Volume= 0.109 af, Depth= 1.89" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) ON Description * 29,650 75 Landscape * 480 98 Concrete path 30,130 75 Weighted Average 29,650 98.41 % Pervious Area 480 1.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, 20-517 Site Rev Type IA 24 -hr 25 yrRainfall=4.80" Prepared by Microsoft Printed 2 /1 912 021 HVdroCAD@ 10.00-i6 s/n 09344 C2015 HVdroCAD Software Solutions LLC Paae 3 Summary for Subcatchment EN: Existing Basin Runoff = 0.10 cfs @ 7.99 hrs, Volume= 0.032 af, Depth= 3.18" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description * 1,395 98 Roof to Downspout 950 98 Driveway 2,950 75 Landscape 5,295 85 Weighted Average 2,950 55.71 % Pervious Area 2,345 44.29% Impervious Area Tc Length Slope Velocity Capacity Description /mint Ifpp11 (ft/fl /ft/cart /rfcl 10.0 Direct Entry, Summary for Subcatchment ES: Existing Basin Runoff = 0.36 cfs @ 8.03 hrs, Volume= 0.132 at, Depth= 2.29" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" ' 29,650 75 Landscape ' 480 98 Concrete path 30,130 75 Weighted Average 29,650 98.41% Pervious Area 480 1.59% Impervious Area Tc Length Slope Velocity Capacity Description mmml Ifpptl Ift/ftl !ff/cprl rrfcl Direct Entry, 20-517 Site Rev Type /A 24 -hr WQ Rainfall=0.83" PreDared by Microsoft Printed 2/19/2021 Summary for Subcatchment EN: Existing Basin Runoff = 0.00 cfs @ 17.50 hrs, Volume= 0.001 af, Depth= 0.10" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN Description * 1,395 98 Roof to Downspout * 950 98 Driveway * 2,950 75 Landscape 5,295 85 Weighted Average 2,950 55.71% Pervious Area 2,345 44.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fusec) (cfs) 10.0 Direct Entry, Summary for Subcatchment ES: Existing Basin Runoff = 0.00 cfs @ 24.01 hrs, Volume= 0.000 af, Depth= 0.01" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN Description * 29,650 75 Landscape * 480 98 Concrete oath 30,130 75 Weighted Average 29,650 98.41 % Pervious Area 480 1.59% Impervious Area Tc Length Slope Velocity Capacity Description Direct Entry, 64 BASIN 2 (Dw.) ST1 3ETRENCH (33') PVr �ARDEN T G - SOAKAGETREA�H PVT RAIN CAREEN (175') �d SAT TRENCH (115') Suhcat Reach on Link B1 BLDG 1 (NORTH) BLDG 2 SOAKAGE TRENCH Gu) NORTH NSR P2 SOUTH MBR 63 BLDG 3 (SOUTH) 20-517 {enter your company name here} Printed 7/28/2021 Area Listing (selected nodes) Area CN Description (acres) (su bcatch ment-n umbers) 0.006 98 GARAGE (134) 0.331 80 LANDSCAPING (B2, B4) 0.017 98 PARKING (P1) 0.254 98 PAVING (B4, P1, P2) 0.329 98 ROOF (B1, B2, B3, B4, P1) 0.937 92 TOTAL AREA 20-517 SiteRev Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD®10.00-24 s/n 09876 @2018 HydroCAD Software Solutions LLC Page 3 Soil Listing (selected nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 0.000 HSG B 0.000 HSG C 0.000 HSG D 0.937 Other B1, B2, B3, B4, P1, P2 0.937 TOTAL AREA 20-517 SiteRev Prepared by {enter your company name here) Printed 7128/2021 HydroCAD® 10 00-24 s/n 09876 @2018 HydroCAD Software Solutions LLC Page 4 Pipe Listing (selected nodes) Line# Node In -Invert Out -Invert Length Slope n DiamNVidth Height Inside -Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 ST1 436.80 438.30 20.0 -0.0750 0.010 3.0 0.0 0.0 2 ST2 436.70 435.80 90.0 0.0100 0.010 4.0 0.0 0.0 3 ST4 436.70 435.80 90.0 0.0100 0.010 6.0 0.0 0.0 4 ST4 436.70 436.60 10.0 0.0100 0.010 6.0 0.0 0.0 20-517 SiteRev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by {enter your company name here) Printed 7/28/2021 HVdroCAD® 10.00-24 s/n 09876 @ 2018 HVdroCAD Software Solutions LLC Pape 5 Summary for Subcatchment B1: BLDG 1 (NORTH) Runoff = 0.02 cfs @ 7.94 hrs, Volume= 0.008 at,, Depth= 4.06" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" * 1,057 98 ROOF * 0 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING * 0 98 PARKING 1,057 98 Weighted Average 1,057 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fusec) (cfs) 10.0 Direct Entry, Summary for Subcatchment B2: BLDG 2 Runoff = 0.21 cfs @ 8.01 hrs, Volume= 0.069 at, Depth= 2.55" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description * 2,764 98 ROOF * 0 98 PAVING 0 98 PATIO * 11,480 80 LANDSCAPING 1. MAMIZIKI� 14,244 83 Weighted Average 11,480 80.60% Pervious Area 2,764 19.40% Impervious Area Tc Length Slope Velocity Capacity Description Summary for Subcatchment B3: BLDG 3 (SOUTH) Runoff = 0.10 cfs @ 7.94 hrs, Volume= 0.034 af, Depth= 4.06" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" 20-517 Site Rev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by (enter your company name here) Printed 7/28/2021 HydroCAD® 10 00-24 s/n 09878 C2018 HydroCAD Software Solutions LLC Paae 6 Area (sf) CN Description * 4,391 98 ROOF * 0 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 4,391 98 Weighted Average 4,391 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 (ft/ft) Direct Entry, Summary for Subcatchment 134: BASIN 2 (Drive) Runoff = 0.10 cfs @ 7.99 hrs, Volume= 0.031 af, Depth= 3.01" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description * 1,745 98 ROOF * 488 98 PAVING * 270 98 GARAGE * 2,950 80 LANDSCAPING 5,453 88 Weighted Average 2,950 98 54.10% Pervious Area 2,503 45.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fUsec) (cfs) 10.0 Direct Entry, Summary for Subcatchment P1: NORTH NBR Runoff = 0.17 as @ 7.94 hrs, Volume= 0.055 at, Depth= 4.06" Runoff by SCS TR -20 method, UH -SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description * 4,391 98 ROOF * 1,965 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING * 725 98 PARKING 7,081 98 Weighted Average 7,081 100.00% Impervious Area 20-517 Site Rev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAM 10.00-24 s/n 09876 @ 2018 HydroCAD Software Solutions LLC Page 7 Tc Length Slope Velocity Capacity Description 10.0 Direct Summary for Subcatchment P2: SOUTH NBR Runoff = 0.20 cfs @ 7.94 hrs, Volume= 0.067 af, Depth= 4.06" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description 0 98 ROOF * 8,603 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 8,603 98 Weighted Average 8,603 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Pond RG 1: PVT RAIN GARDEN Inflow Area = 0.163 ac,100.00% Impervious, Inflow Depth = 4.06" for 10 yr event Inflow = 0.17 cfs @ 7.94 hrs, Volume= 0.055 of Outflow = 0.09 cfs @ 8.27 hrs, Volume= 0.055 af, Allen= 44%, Lag= 20.0 min Primary = 0.02 cfs @ 8.27 hrs, Volume= 0.046 of Secondary= 0.07 cfs @ 8.27 hrs, Volume= 0.009 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Bev= 438.38'@ 8.27 hrs Surf.Area= 479 sf Storage= 614 cf Plug -Flow detention time= 291.6 min calculated for 0.055 of (100% of inflow) Center -of -Mass det. time= 291.6 min ( 953.5 - 661.9 ) Volume Invert Avail.Storage Storage Description #1 436.50' 674of Custom Stage Data (Prismatic)-isted below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 436.50 175 0 0 438.50 499 674 674 Device Routing Invert Outlet Devices #1 Primary 436.50' 2.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Secondary 438.25' 0.5' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 1.0' Crest Height 20-517 Site Rev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by (enter your company name here) Printed 7/28/2021 HvdroCAD® 10.00-24 s/n 09876 @ 2018 HvdroCAD Software Solutions LLC Page 8 rimary OutFlow Max=0.02 cis @ 8.27 hrs HW=438.38' TW=434.29' (Dynamic Tailwater) 1=Exfiltration (Exfiltration Controls 0.02 cfs) Secondary OutFlow Max=0.07 cfs @ 8.27 hrs HW=438.38' TW=434.29' (Dynamic Tailwater) 2=Sharp-Crested Rectangular Weir(Weir Controls 0.07 cfs @ 1.18 fps) Summary for Pond RG 2: PVT RAIN GARDEN Inflow Area = 0.197 ac,100.00% Impervious, Inflow Depth = 4.06" for 10 yr event Inflow = 0.20 cfs @ 7.94 hrs, Volume= 0.067 of Outflow = 0.20 cfs @ 8.01 hrs, Volume= 0.067 af, Atten= 1%, Lag= 4.2 min Primary = 0.02 cfs @ 8.01 hrs, Volume= 0.048 of Secondary= 0.18 cfs @ 8.01 hrs, Volume= 0.019 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 438.34'@ 8.01 hrs Surf.Area= 473 sf Storage= 596 cf Plug -Flow detention time= 257.5 min calculated for 0.067 of (100% of inflow) Center -of -Mass det. time= 257.5 min ( 919.4 - 661.9 ) Volume Invert Avail.Storage Storage Description #1 436.50' 674 cf Custom Stage Data (Prismatic)-isted below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 436.50 175 0 0 438.50 499 674 674 Device Routing Invert Outlet Devices #1 Primary 436.50' 2.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Secondary 438.25' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 1.0' Crest Height Primary OutFlow Max=0.02 cfs @ 8.01 hrs HW=438.34' TW=434.09' (Dynamic Tailwater) L1=Exfiltration (Exfiltration Controls 0.02 cfs) Secondary OutFlow Max=0.18 cfs @ 8.01 hrs HW=438.34' TW=434.09' (Dynamic Tailwater) 2=Sharp-Crested Rectangular Weir(Weir Controls 0.18 cfs @ 0.99 fps) Summary for Pond ST1: SOAKAGE TRENCH (33') Inflow Area = 0.837 ac, 60.40% Impervious, Inflow Depth = 0.45" for 10 yr event Inflow = 0.10 cfs @ 7.99 hrs, Volume= 0.031 of Outflow = 0.02 cfs @ 13.51 hrs, Volume= 0.031 af, Atten= 81%, Lag= 331.5 min Discarded = 0.01 cfs @ 5.84 hrs, Volume= 0.026 of Primary = 0.01 cfs @ 13.51 hrs, Volume= 0.006 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs 20-517 SiteRev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by {enter your company name here) Printed 7/2812021 HydroCAD® 10.00-24 s/n 09876 Q2018 HydroCAD Software Solutions LLC Page 9 Peak Elev= 438.37'@ 13.51 hrs Surr.Area= 201 sf Storage= 608 of Plug -Flow detention time= 723.7 min calculated for 0.031 of (99% of inflow) Center -of -Mass det. time= 719.4 min ( 1,463.9 - 744.5 ) Volume Invert Avail.Storage Storage Description #1 434.00' 387 of 6.00'W x 33.00'L x 3.00'H Prismatoid 594 of Overall - 207 of Embedded = 387 of #2 434.00' 25 of 2.00'D x 8.00'H Vertical Cone/Cylinder 43 434.50' 207 of 24.0" Round Pipe Storage Inside #1 L= 66.0' 619 of Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In -0.01' #2 Primary 438.30' 3.0" Round Culvert L=20.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.80'1438.30' S=-0.07507 Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.05 sf Discarded OutFlow Max=0.01 cfs @ 5.84 hrs HW=434.08' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.01 cfs @ 13.51 hrs HW=438.37' (Free Discharge) t2=Culvert (Inlet Controls 0.01 cfs @ 0.91 fps) Summary for Pond ST2: SOAKAGE TRENCH (86') Inflow Area = 0.327 ac, 19.40% Impervious, Inflow Depth = 2.55" for 10 yr event Inflow = 0.21 cfs @ 8.01 hrs, Volume= 0.069 of Outflow = 0.14 cfs @ 8.20 hrs, Volume= 0.069 af, Atten= 30%, Lag= 11.4 min Discarded = 0.01 cfs @ 5.61 hrs, Volume= 0.031 of Primary = 0.13 cfs @ 8.20 hrs, Volume= 0.039 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 436.97'@ 8.20 hrs Surf.Area= 347 sf Storage= 505 of Plug -Flow detention time= 214.6 min calculated for 0.069 of (100% of inflow) Center -of -Mass det. time= 214.7 min ( 991.0 - 776.3 ) Volume Invert Avail.Storage Storage Description #1 434.00' 229 of 4.00'W x 86.00'L x 3.00'H Prismatoid 1,032 of Overall - 270 of Embedded = 762 of x 30.0% Voids #2 434.50' 270 of 24.0" Round Pipe Storage Inside #1 L= 86.0' #3 434.00' 25 of 2.00'D x 8.00'H Vertical Cone/Cylinder 524 of Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 436.70' 4.0" Round Culvert 20-517 Site Rev Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD® 10.00-24 s/n 09876 © 2018 HydroCAD Software Solutions LLC Page 10 L= 90.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'1435.80' S=0.01007 Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.09 sf D rded OutFlow Max=0.01 cfs @ 5.61 hrs HW=434.08' (Free Discharge) ttExfiltration (Exfiltration Controls 0.01 cfs) triOutFlow Max=0.13 cfs @ 8.20 hrs HW=436.97' TW=434.22' (Dynamic Tailwater) 2=Culvert (Inlet Controls 0.13 cfs @ 1.76 fps) Summary for Pond ST3: SOAKAGE TRENCH (115') Inflow Area = 0.101 ac,100.00% Impervious, Inflow Depth = 4.06" for 10 yr event Inflow = 0.10 cfs @ 7.94 hrs, Volume= 0.034 of Outflow = 0.02 cfs @ 5.73 hrs, Volume= 0.034 af, Atten= 84%, Lag= 0.0 min Discarded = 0.02 cfs @ 5.73 hrs, Volume= 0.034 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 435.65'@ 12.70 hrs Surf.Area= 463 sf Storage= 385 cf Plug -Flow detention time= 239.3 min calculated for 0.034 of (100% of inflow) Center -of -Mass det. time= 239.3 min ( 901.2 - 661.9 ) Volume Invert Avail.Storage Storage Description #1 434.00' 306 cf 4.00'W x 115.00%x 3.00'H Prismatoid 1,380 cf Overall - 361 d Embedded = 1,019 of x 30.0% Voids #2 434.50' 361 cf 24.0" Round Pipe Storage Inside #1 L= 115.0' #3 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 692 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' Discarded OutFlow Max=0.02 cfs @ 5.73 hrs HW=434.08' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.02 ds) Summary for Pond ST4: SOAKAGE TRENCH (175') Inflow Area = 0.711 ac, 62.95% Impervious, Inflow Depth = 2.85" for 10 yr event Inflow = 0.39 cfs @ 8.18 hrs, Volume= 0.169 of Outflow = 0.08 cfs @ 7.99 hrs, Volume= 0.169 af, Atten= 80%, Lag= 0.0 min Discarded = 0.08 cfs @ 7.99 hrs, Volume= 0.169 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 435.67'@ 15.48 hrs SurF.Area= 2,291 sf Storage= 1,413 cf Plug -Flow detention time= 185.2 min calculated for 0.169 of (100% of inflow) Center -of -Mass det. time= 185.2 min ( 1,083.3 - 898.1 ) 20-517 Site Rev Type IA 24 -hr 10 yrRainfall=4.30" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD® 10.00-24 s/n 09876 © 2018 HydroCAD Software Solutions LLC Pane 11 Volume Invert Avail.Storage Storage Description #1 434.00' 400 cf 8.00'W x 100.00'L x 0.50'H Prismatoid #2 434.00' 1,155 cf 8.50'W x 175.00'L x 3.00'H Prismatoid 4,463 cf Overall - 613 cf Embedded = 3,850 cf x 30.0% Voids #3 434.50' 613 cf 24.0" Round Pipe Storage Inside #2 L= 195.0' #4 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 2,193 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 436.70' 6.0" Round Culvert L=90.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'/435.80' S=0.01007 Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.20 sf #3 Secondary 436.70' 6.0" Round Culvert L=10.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'/ 436.60' S= 0.0100 T Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf Discarded OutFlow Max=0.08 cfs @ 7.99 hrs H W=434.08' (Free Discharge) 1-1=Exfiltration (Exfiltration Controls 0.08 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=434.00' TW=434.00' (Dynamic Tailwater) L2=Culvert ( Controls 0.00 cfs) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=434.00' TW=434.00' (Dynamic Tailwater) 3=Culvert ( Controls 0.00 cfs) 20-517 Site Rev Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD@ 10.00-24 s/n 09876 @2018 HydroCAD Software Solutions LLC Page 12 Summary for Subcatchment B1: BLDG 1 (NORTH) Runoff = 0.03 cfs @ 7.94 hrs, Volume= 0.009 af, Depth= 4.56" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (so CN Description * 1,057 98 ROOF * 0 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 1,057 98 Weighted Average 1,057 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment B2: BLDG 2 Runoff = 0.25 cfs @ 8.01 hrs, Volume= 0.082 af, Depth= 2.99" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description * 2,764 98 ROOF * 0 98 PAVING 0 98 PATIO * 11,480 80 LANDSCAPING * 0 98 PARKING 14,244 83 Weighted Average 11,480 80.60% Pervious Area 2,764 19.40% Impervious Area Tc Length Slope Velocity Capacity Description 10.0 Direct Entry, Summary for Subcatchment 133: BLDG 3 (SOUTH) Runoff = 0.11 cfs @ 7.94 hrs, Volume= 0.038 af, Depth= 4.56" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" 20-517 SiteRev Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by (enter your company name here) Printed 7/28/2021 HydroCAD®10.00-24 s/n 09876 © 2018 HydroCAD Software Solutions LLC Paae 13 4,391 98 ROOF 0 98 PAVING 0 98 PATIO 4,391 98 Weighted Average 4,391 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 134: BASIN 2 (Drive) Runoff = 0.11 cfs @ 7.99 hrs, Volume= 0.036 at, Depth= 3.48" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description * 1,745 98 ROOF * 488 98 PAVING * 270 98 GARAGE * 2,950 80 LANDSCAPING 5,453 88 Weighted Average 2,950 54.10% Pervious Area 2,503 45.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment P1: NORTH NBR Runoff = 0.19 cfs @ 7.94 hrs, Volume= 0.062 at, Depth= 4.56" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" * 4,391 98 ROOF * 1,965 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 725 98 PARKING 7,081 98 Weighted Average 7,081 100.00% Impervious Area 20-517 Site Rev Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by (enter your company name here) Printed 7/28/2021 HvdroCAD® 10.00-24 s/n 09876 02018 HvdmCAD Software Solutions LLC Page 14 Tc Length Slope Velocity Capacity Description Direct Entry, Summary for Subcatchment 132: SOUTH NBR Runoff = 0.23 cfs @ 7.94 hrs, Volume= 0.075 af, Depth= 4.56" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description 0 98 ROOF * 8,603 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 8,603 98 Weighted Average 8,603 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f/sec) (cfs) 10.0 Direct Entry, Summary for Pond RG 1: PVT RAIN GARDEN Inflow Area = 0.163 ac,100.00% Impervious, Inflow Depth = 4.56" for 25 yr event Inflow = 0.19 cfs @ 7.94 hrs, Volume= 0.062 of Outflow = 0.14 cfs @ 8.14 hrs, Volume= 0.062 af, Atten= 22%, Lag= 12.1 min Primary = 0.02 cfs @ 8.14 hrs, Volume= 0.047 of Secondary= 0.12 cfs @ 8.14 hrs, Volume= 0.014 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 438.43'@ 8.14 hrs Surf.Area= 488 sf Storage= 641 cf Plug -Flow detention time=274.2 min calculated for 0.062 of (100% of inflow) Center -of -Mass det. time= 274.3 min ( 933.8 - 659.5 ) Volume Invert Avail.Storage Storage Description 41 436.50' 674c' Custom Stage Data (Prismatic)-isted below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 436.50 175 0 0 438.50 499 674 674 Device Routing Invert Outlet Devices #1 Primary 436.50' 2.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Secondary 438.25' 0.5' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 1.0' Crest Height 20-517 SiteRev Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by (enter your company name here} Printed 7/28/2021 HvdroCAD® 10.00-24 s/n D9876 @2018 HvdroCAD Software Solutions LLC Paoe 15 Primary OutFlow Max=0.02 cfs @ 8.14 hrs HW=438.43' TW=434.43' (Dynamic Tailwater) t1=Ex1filtration (Exfiltration Controls 0.02 cfs) Secondary OutFlow Max=0.12 cfs @ 8.14 hrs HW=438.43' TW=434.43' (Dynamic Tailwater) 2=Sharp-Crested Rectangular Weir(Weir Controls 0.12 cfs @ 1.43 fps) Summary for Pond RG 2: PVT RAIN GARDEN Inflow Area = 0.197 ac,100.00% Impervious, Inflow Depth = 4.56" for 25 yr event Inflow = 0.23 cfs @ 7.94 hrs, Volume= 0.075 of Outflow = 0.22 cfs @ 7.99 hrs, Volume= 0.075 af, Atten= 1%, Lag= 2.7 min Primary = 0.02 cfs @ 7.99 hrs, Volume= 0.049 of Secondary- 0.20 cfs @ 7.99 hrs, Volume= 0.026 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 438.35'@ 7.99 hrs Surf.Area= 474 sf Storage= 600 cf Plug -Flow detention time=237.6 min calculated for 0.075 of (100% of inflow) Center -of -Mass det. time= 237.7 min ( 897.2 - 659.5 ) Volume Invert Avail.Storage Storage Description #1 436.50' 674 cf Custom Stage Data (Prismatic)-isted below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 436.50 175 0 0 438.50 499 674 674 Device Routing Invert Outlet Devices #1 Primary 436.50' 2.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Secondary 438.25' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 1.0' Crest Height Primary OutFlow Max=0.02 cfs @ 7.99 hrs HW=438.35' TW=434.20' (Dynamic Tailwater) t1=Exfiltration (Exfiltration Controls 0.02 cfs) Secondary OutFlow lcfs @ 7.99 hrs HW=438.35' TW=434.20' (Dynamic Tailwater) 2=Sharp-Crested Rectangular Weir(Weir Controls 0.20 cfs @ 1.04 fps) Summary for Pond ST1: SOAKAGE TRENCH (33') Inflow Area = 0.837 ac, 60.40% Impervious, Inflow Depth = 0.52" for 25 yr event Inflow = 0.11 cfs @ 7.99 hrs, Volume= 0.036 of Outflow = 0.03 cfs @ 10.84 hrs, Volume= 0.036 af, Atten= 74%, Lag= 171.2 min Discarded = 0.01 cfs @ 5.40 hrs, Volume= 0.026 of Primary = 0.02 cfs @ 10.84 hrs, Volume= 0.010 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs 20-517 Site Rev Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by (enter your company name here) Printed 7/2812021 HydroCAD510.00-24 s/n 09876 @2018 HydroCAD Software Solutions LLC Page 16 Peak Elev= 438.40'@ 10.84 hrs Surf.Area= 201 sf Storage= 608 of Plug -Flow detention time= 643.4 min calculated for 0.036 of (99% of inflow) Center -of -Mass det. time= 639.6 min ( 1,376.6 - 736.9 ) Volume Invert Avail.Storage Storage Description #1 434.00' 387 of 6.00'W x 33.00'L x 3.00'H Prismatoid 594 of Overall - 207 of Embedded = 387 of #2 434.00' 25 of 2.00'D x 8.00'H Vertical Cone/Cylinder #3 434.50' 207 of 24.0" Round Pipe Storage Inside #1 L= 66.0' 619 of Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 438.30' 3.0" Round Culvert L=20.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.80'/438.30' S= -0.0750'P Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.05 sf Discarded OutFlow Max=0.01 cfs @ 5.40 hrs HW=434.08' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.02 cfs @ 10.84 hrs HW=438.40' (Free Discharge) L2=Culvert (Inlet Controls 0.02 cfs @ 1.08 fps) Summary for Pond ST2: SOAKAGE TRENCH (86') Inflow Area = 0.327 ac, 19.40% Impervious, Inflow Depth= 2.99" for 25 yr event Inflow = 0.25 cfs @ 8.01 hrs, Volume= 0.082 of Outflow = 0.27 cfs @ 7.98 hrs, Volume= 0.082 af, Atten= 0%, Lag= 0.0 min Discarded = 0.01 cfs @ 5.21 hrs, Volume= 0.031 of Primary = 0.26 cfs @ 7.98 hrs, Volume= 0.050 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 437.30'@ 7.98 hrs Surf.Area= 347 sf Storage= 509 of Plug -Flow detention time= 187.3 min calculated for 0.082 of (100% of inflow) Center -of -Mass det. time= 187.4 min ( 954.5 - 767.1 ) Volume Invert Avail.Storage Storage Description #1 434.00' 229 of 4.00'W x 86.00'L x 3.00'11 Prismatoid 1,032 of Overall - 270 of Embedded = 762 of x 30.0% Voids #2 434.50' 270 of 24.0" Round Pipe Storage Inside #1 L= 86.0' #3 434.00' 25 of 2.00'D x 8.00'H Vertical Cone/Cylinder 524 of Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 436.70' 4.0" Round Culvert 20-517_SiteRev Type IA 24 -hr 25 yrRainfall=4.80" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD® 10.00-24 s/n 09876 @ 2018 HydroCAD Software Solutions LLC Pace 17 L= 90.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'/435.80' S= 0.0100'/' Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.09 sf Discarded OutFlow Max=0.01 cfs @ 5.21 hrs HW=434.08' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.25 cfs @ 7.98 hrs HW=437.25' TW=434.19' (Dynamic Tailwater) t2=Culvert (Barrel Controls 0.25 cfs @ 2.87 fps) Summary for Pond ST3: SOAKAGE TRENCH (115') Inflow Area = 0.101 ac,100.00% Impervious, Inflow Depth = 5.09" for 25 yr event Inflow = 0.11 cfs @ 7.94 hrs, Volume= 0.043 of Outflow = 0.02 cfs @ 5.25 hrs, Volume= 0.043 af, Atten= 86%, Lag= 0.0 min Discarded = 0.02 cfs @ 5.25 hrs, Volume= 0.043 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 436.87'@ 17.62 hrs Surf.Area= 463 sf Storage= 659 cf Plug -Flow detention time= 392.3 min calculated for 0.043 of (100% of inflow) Center -of -Mass del. time= 392.4 min ( 1,074.2 - 681.8 ) Volume Invert Avail.Storage Storage Description 41 434.00' 306 cf 4.00'W x 115.00'L x 3.00'H Prismatoid 1,380 cf Overall - 361 cf Embedded = 1,019 cf x 30.0% Voids #2 434.50' 361 of 24.0" Round Pipe Storage Inside #1 L= 115.0' #3 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 692 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' Discarded OutFlow Max=0.02 cfs @ 5.25 hrs HW=434.08' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.02 cfs) Summary for Pond ST4: SOAKAGE TRENCH (175') Inflow Area = 0.711 ac, 62.95% Impervious, Inflow Depth = 3.32" for 25 yr event Inflow = 0.61 cfs @ 8.06 hrs, Volume= 0.197 of Outflow = 0.10 cfs @ 13.51 hrs, Volume= 0.197 af, Atten= 83%, Lag= 327.4 min Discarded = 0.08 cfs @ 7.84 hrs, Volume= 0.192 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Secondary= 0.02 cfs @ 13.51 hrs, Volume= 0.004 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 436.87'@ 17.63 hrs Surf.Area= 2,291 sf Storage= 2,121 cf Plug -Flow detention time= 290.1 min calculated for 0.197 of (100% of inflow) Center -of -Mass det. time= 290.1 min ( 1,166.6 - 876.5 ) 20-517 Site Rev Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by {enter your company name here) Printed 7/28/2021 HvdroCAD@ 10.00-24 s/n 09876 © 2018 HydroCAD Software Solutions LLC Page 18 Volume Invert Avail.Storage Storage Description #1 434.00' 400 cf 8.00'W x 100.00'L x 0.50'H Prismatoid #2 434.00' 1,155 cf 8.50'W x 175.00'L x 3.00'H Prismatoid 4,463 cf Overall - 613 cf Embedded = 3,850 cf x 30.0% Voids #3 434.50' 613 cf 24.0" Round Pipe Storage Inside #2 L= 195.0' #4 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 2,193 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 436.70' 6.0" Round Culvert L=90.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'/ 435.80' S=0.0100? Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf #3 Secondary 436.70' 6.0" Round Culvert L=10.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'/ 436.60' S= 0.0100'1' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf Discarded OutFlow Max=0.08 cfs @ 7.84 hrs HW=434.08' (Free Discharge) L7=Exfiltration (Exfiltration Controls 0.08 cfs) Zrimary OutFlow Max=0.00 cfs @ 0.00 hrs HW=434.00' TW=434.00' (Dynamic Tailwater) 2=Culvert ( Controls 0.00 cfs) Secondary OutFlow Max=0.02 cfs @ 13.51 hrs HW=436.79' TW=436.22' (Dynamic Tailwater) 3=Culvert (Barrel Controls 0.02 cfs @ 1.48 fps) 20-517 Site Rev Type IA 24 -hr WQ Rainfall=0.83" Prepared by (enter your company name here) Printed 7/2812021 HydraCAD@ 10.00-24 s/n 09876 @2018 HydroCAD Software Solutions LLC Fade 19 Summary for Subcatchment 131: BLDG 1 (NORTH) Runoff = 0.00 cfs @ 7.97 hrs, Volume= 0.001 af, Depth= 0.63" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN Description * 1,057 98 ROOF * 0 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 0 98 PARKING 1,057 98 Weighted Average 1,057 100.00% Impervious Area Tc Length Slope Velocity Capacity Description Direct Entry, Summary for Subcatchment B2: BLDG 2 Runoff = 0.00 cfs @ 18.79 hrs, Volume= 0.002 af, Depth= 0.07" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN Description * 2,764 98 ROOF * 0 98 PAVING 0 98 PATIO * 11,480 80 LANDSCAPING 0 98 PARKING 14,244 83 Weighted Average 11,480 80.60% Pervious Area 2,764 19.40% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment B3: BLDG 3 (SOUTH) Runoff = 0.02 cfs @ 7.97 hrs, Volume= 0.005 af, Depth= 0.63" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" 20-517 SiteRev Type IA 24 -hr WQ Rainfall=0.83" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD®10 00-24 s/n 09876 © 2018 HydroCAD Software Solutions LLC Paae 20 Area (sf) CN Description * 4,391 98 ROOF * 0 98 PAVING 0 98 PATIO 0 80 LANDSCAPING 4,391 98 Weighted Average 4,391 98 100.00% Impervious Area To Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fUsec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 134: BASIN 2 (Drive) Runoff = 0.00 cfs @ 8.08 hrs, Volume= 0.002 af, Depth= 0.16" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN Description * 1,745 98 ROOF * 488 98 PAVING * 270 98 GARAGE * 2,950 80 LANDSCAPING 5,453 88 Weighted Average 2,950 98 54.10% Pervious Area 2,503 45.90% Impervious Area To Length Slope Velocity Capacity Description 10.0 Entry, Summary for Subcatchment P1: NORTH NBR Runoff = 0.03 cfs @ 7.97 hrs, Volume= 0.008 af, Depth= 0.63" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN Description * 4,391 98 ROOF * 1,965 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING * 725 98 PARKING 7,081 98 Weighted Average 7,081 100.00% Impervious Area 20-517 Site Rev Type IA 24 -hr WQ Rainfall=0.83" Prepared by (enter your company name here) Printed 7/28/2021 HydroCAD@ 10.00-24 s/n 09876 02018 HydroGAD Software Solutions LLC Page 21 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment P2: SOUTH NBR Runoff = 0.03 cfs @ 7.97 hrs, Volume= 0.010 af, Depth= 0.63" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type IA 24 -hr WQ Rainfall=0.83" Area (sf) CN 0 98 ROOF * 8,603 98 PAVING 0 98 PATIO * 0 80 LANDSCAPING 8,603 98 Weighted Average 8,603 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Pond RG 1: PVT RAIN GARDEN Inflow Area= 0.163 ac,100.00%Impervious, Inflow Depth= 0.63" for WQ event Inflow = 0.03 cfs @ 7.97 hrs, Volume= 0.008 of Outflow = 0.01 cfs @ 8.88 hrs, Volume= 0.008 of, Men= 64%, Lag= 54.5 min Primary = 0.01 cfs @ 8.88 hrs, Volume= 0.008 of Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 436.70'@ 8.88 hrs Surf.Area= 208 sf Storage= 39 cf Plug -Flow detention time= 20.8 min calculated for 0.008 of (100% of inflow) Center -of -Mass det. time= 20.8 min ( 748.4 - 727.6 ) Volume Invert Avail.Storage Storage Description #1 436.50' 674 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 436.50 175 0 0 438.50 499 674 674 Device Routing Invert Outlet Devices #1 Primary 436.50' 2.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Secondary 438.25' 0.5' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 1.0' Crest Height 20-517 SiteRev Type IA 24 -hr WQ Rainfall=0.83" Prepared by {enter your company name here) Printed 7/28/2021 HvdroCAD®10.00-24 s/n 09876 © 2018 HvdroCAD Software Solutions LLC Pape 22 Primary OutFlow Max=0.01 cfs @ 8.88 hrs HW=436.70' TW=434.00' (Dynamic Tailwater) 't-1=Exflltration (Exfltration Controls 0.01 cfs) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=436.50' TW=434.00' (Dynamic Tailwater) 2=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond RG 2: PVT RAIN GARDEN Inflow Area = 0.197 ac,100.00% Impervious, Inflow Depth = 0.63" for WQ event Inflow = 0.03 cfs @ 7.97 hrs, Volume= 0.010 of Outflow = 0.01 cfs @ 9.10 hrs, Volume= 0.010 af, Atten= 68%, Lag= 68.0 min Primary = 0.01 cfs @ 9.10 hrs, Volume= 0.010 of Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 436.79'@ 9.10 hrs Surf.Area= 221 sf Storage= 57 cf Plug -Flow detention time= 32.8 min calculated for 0.010 of (100% of inflow) Center -of -Mass det. time= 32.8 min ( 760.5 - 727.6 ) Volume Invert Avail.Storage Storage Description #1 436.50' 674 cf Custom Stage Data (Prismatic)-isted below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 436.50 175 0 0 438.50 499 674 674 Device Routing Invert Outlet Devices #1 Primary 436.50' 2.000 in/hr Exfiltration over Surface area Phase -In= 0.01' 42 Secondary 438.25' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 1.0' Crest Height rimary OutFlow Max=0.01 cfs @ 9.10 hrs HW=436.79' TW=434.00' (Dynamic Tailwater) 1=Exfiltration (Exfltration Controls 0.01 cfs) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=436.50' TW=434.00' (Dynamic Tailwater) 2=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond STI: SOAKAGE TRENCH (33') Inflow Area = 0.837 ac, 60.40% Impervious, Inflow Depth = 0.02" for WQ event Inflow = 0.00 cfs @ 8.08 hrs, Volume= 0.002 of Outflow 0.00 cfs @ 8.17 hrs, Volume= 0.002 af, Atten= 8%, Lag= 5.2 min Discarded = 0.00 cfs @ 8.17 hrs, Volume= 0.002 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs 20-517 SiteRev Type IA 24 -hr WQ Rainfall=0.83" Prepared by (enter your company name here) Printed 7/28/2021 HvdroCADe 10.00-24 sinO9876 @2018 HvdroCAD Software Solutions LLC Pace 23 Peak Elev= 434.00'@ 8.17 hrs Surf.Area= 201 sf Storage= 1 cf Plug -Flow detention time= 4.8 min calculated for 0.002 of (100% of inflow) Center -of -Mass det. time= 4.8 min ( 939.3 - 934.5 ) Volume Invert Avail.Storage Storage Description #1 434.00' 387 cf 6.00'W x 33.00'L x 3.00'H Prismatoid 594 cf Overall - 207 cf Embedded = 387 cf #2 434.00' 25 cf 2.001D x 8.001H Vertical Cone/Cylinder #3 434.50' 207 cf 24.0" Round Pipe Storage Inside #1 619 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 438.30' 3.0" Round Culvert L= 20.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.80'/438.30' S=-0.0750? Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.05 sf Discarded OutFlow Max=0.00 cfs @ 8.17 hrs HW=434.00' (Free Discharge) 1=Exfiltratlon (Exfiltration Controls 0.00 cfs) rimary OutFlow Max=0.00 cfs @ 0.00 hrs HW=434.00' (Free Discharge) 2=Culvert ( Controls 0.00 cfs) Summary for Pond ST2: SOAKAGE TRENCH (86') Inflow Area = 0.327 ac, 19.40% Impervious, Inflow Depth = 0.07" for WQ event Inflow = 0.00 cfs @ 18.79 hrs, Volume= 0.002 of Outflow = 0.00 cfs @ 18.84 hrs, Volume= 0.002 af, Atten= 0%, Lag= 2.9 min Discarded = 0.00 cfs @ 18.84 hrs, Volume= 0.002 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 434.00'@ 18.84 hrs Surf.Area= 347 sf Storage= 0 cf Plug -Flow detention time= 1.5 min calculated for 0.002 of (100% of inflow) Center -of -Mass det. time= 1.5 min ( 1,042.1 - 1,040.6 ) Volume Invert Avail.Storage Storage Description 41 434.00' 229 of 4.00'W x 86.00'L x 3.0011 Prismatoid 1,032 cf Overall - 270 cf Embedded = 762 cf x 30.0% Voids #2 434.50' 270 cf 24.0" Round Pipe Storage Inside #1 L= 86.0' #3 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 524 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 436.70' 4.0" Round Culvert 20-517 SiteRev Type IA 24 -hr WQ Rainfall=0.83" Prepared by {enter your company name here} Printed 7/28/2021 HvdroCAD(D 10.00-24 s/n 09876 © 2018 HvdroCAD Software Solutions LLC Page 24 L= 90.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 436.70'/ 435.80' S=0.0100'/' Cc= 0.900 n=0.010 PVC, smooth interior, Flow Area= 0.09 sf Discarded OutFlow Max=0.00 cfs @ 18.84 hrs HW=434.00' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.00 cfs) Primary Outflow Max=0.00 cfs @ 0.00 hrs HW=434.00' TW=434.00' (Dynamic Tailwater) L2=Culvert ( Controls 0.00 cfs) Summary for Pond STI SOAKAGE TRENCH (115') Inflow Area 0.101 ac,100.00%Impervious, Inflow Depth= 0.63" for WQ event Inflow = 0.02 cfs @ 7.97 hrs, Volume= 0.005 of Outflow = 0.02 cfs @ 8.05 hrs, Volume= 0.005 af, Atten= 2%, Lag= 4.6 min Discarded = 0.02 cfs @ 8.05 hrs, Volume= 0.005 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 434.01'@ 8.05 hrs Surf.Area= 463 sf Storage= 2 cf Plug -Flow detention time= 1.5 min calculated for 0.005 of (100% of inflow) Center -of -Mass det. time= 1.5 min ( 729.1 - 727.6 ) Volume Invert Avail.Storage Storage Description #1 434.00' 306 of 4.00'W x 115.00'L x 3.00'H Prismatoid Volume= 0.020 af, Atten= 0%, Lag= 2.1 min Discarded = 1,380 cf Overall - 361 cf Embedded = 1,019 cf x 30.0% Voids #2 434.50' 361 cf 24.0" Round Pipe Storage Inside #1 0.00 cfs @ 0.00 hrs, Volume= L= 115.0' #3 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 0.000 of Routing by Dyn-Stor-Ind 692 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' Discarded OutFlow Max=0.02 cfs @ 8.05 hrs HW=434.01' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.02 cfs) Summary for Pond ST4: SOAKAGE TRENCH (175') Inflow Area = 0.711 ac, 62.95% Impervious, Inflow Depth = 0.34" for WQ event Inflow = 0.02 cfs @ 8.06 hrs, Volume= 0.020 of Outflow = 0.02 cfs @ 8.10 hrs, Volume= 0.020 af, Atten= 0%, Lag= 2.1 min Discarded = 0.02 cfs @ 8.10 hrs, Volume= 0.020 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Peak Elev= 434.00'@ 8.10 hrs Surf.Area= 2,291 sf Storage= 4 cf Plug -Flow detention time=2.6 min calculated for 0.020 of (100% of inflow) Center -of -Mass det. time= 2.6 min ( 755.9 - 753.3 ) 20-517 SiteRev Type IA 24 -hr WQ Rainfall=0.83" Prepared by {enter your company name here) Printed 7/28/2021 HydroCAD® 10.00-24 s/n 09876 © 2018 HydroCAD Software Solutions LLC Page 25 Volume Invert Avail.Storage Storage Description #1 434.00' 400 cf 8.00'W x 100.00'L x 0.50'H Prismatoid #2 434.00' 1,155 cf 8.50'W x 175.00'L x 3.00'H Prismatoid 4,463 cf Overall - 613 cf Embedded = 3,850 cf x 30.0% Voids #3 434.50' 613 cf 24.0" Round Pipe Storage Inside #2 L= 195.0' #4 434.00' 25 cf 2.00'D x 8.00'H Vertical Cone/Cylinder 2,193 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 434.00' 1.500 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 436.70' 6.0" Round Culvert L=90.0' CMP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.70'/435.80' S=0.011007 Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf #3 Secondary 436.70' 6.0" Round Culvert L=10.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 436.70'/ 436.60' S=0.01007 Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf Discarded OutFlow Max=0.02 cfs @ 8.10 hrs HW=434.00' (Free Discharge) t-1=Exf11tration (Exfiltration Controls 0.02 cfs) Zrimary OutFlow Max=0.00 cfs @ 0.00 hrs HW=434.00' TW=434.00' (Dynamic Tailwater) 2=Culvert ( Controls 0.00 cfs) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=434.00' TW=434.00' (Dynamic Tailwater) 3=Culvert ( Controls 0.00 cfs) APPENDIX B Infiltration Test Summary Soil Map Soil Description ranch E'NIGINEERING- sm,19n February 12, 2020 Sebmirer Satre Group 375 W 4th Ave #201 Eugene, Or 97401 RE: SITE INFILTRATION TEST RESULT'S 287 DEADMONu Frnuy RoAn SPRINGFIFLD, OREGON REI PROJECT No. 20-S17 Branch Engineering Inc. (BEI) has performed infiltration testing in two hand -augured test holes located near the northwest and southwest corner of the lot. The purpose of our testing was to provide a site-specific infiltration rate for the design of on-site infiltration facilities for the disposal of stormwaLU generated from new impervious surface areas. Field Work and Site Description Two approximately 6 -inch diameter hand auger holes were advanced to a maximum depth of 43 - inches below ground surface (BGS). On January 4, 2021 a Falling Head Infiltration Test were performed in accordance with the 2014 City of Eugene Stormwater Manual. Infiltration testing commenced for three successive trials with water added between each trial, field data is attached. At the time of testing the site is occupied by a residential house and a shed/outbuilding The rest of the site is bare soil covered with vegetation. Soils The soil in the test hole was visually classified using the American Society of Testing and Materials (ASTM) Method D-2488. Soil conditions from approximately 0- to 8 -inches BGS consisted of soft, damp, brown silty clay before transitioning to medium stiff, moist, brown clayey silt. The NRCS Web Soil Survey of the Lane County Area maps the site soil as Malabon silty clay loam which is described as moderately well drained class C soil. Slmimary of Field Infiltration Test Results The results of our January 4, 2021 field testing are summarized below in Table 1. The hydraulic conductivity is based on the infiltration rates measured in the field and summarized on the attached Infiltration Testing Field Data. The rates shown below have no factors of safety applied and represent the slowest infiltration rate measured of the three trials. EUGFNE-SPRINCRELD PHILOMATH-CORVALLIS 310 5�h Street, Springfield, 0R 97477 1 p: S41.746.0637 I w .hranchengineering.coro Measured Rate of Depth of Hydraulic Conductivity, Location Test (in) k (in/hr) Infiltration Test IT -1 43 2.5 Infiltration Test IT -2 43 3.5 EUGFNE-SPRINCRELD PHILOMATH-CORVALLIS 310 5�h Street, Springfield, 0R 97477 1 p: S41.746.0637 I w .hranchengineering.coro 287 Deadmond Ferry Infiltration Testing February 12, 2021 Recommended Infiltration Design Rates Using the recommended factor of safety of 2, a design infiltration rate of 1.5 in/hr for the site is suggested. Safety factors may be applied at the discretion of the designer and the 2014 City of Eugene Stormwater Manual. Conclusions Based on our field findings and infiltration testing results, disposal of stormwater via infiltration facilities on the site is feasible. if you have any questions regarding the test method, data analysis or design, please contact the undersigned. Sincerely, Branch Engineering Inc, 0 Pf?o _ WN #7923 PE Digitally Signed Digitally signed by Nathan Patterson OREGON te: 2021.07.3009:53:14-07'00' �� QFC, 2i � 2�y� Q$ EXPIRES: 12/31/22 Nathan Patterson, P.E. Principal Civil Engineer Attached: Infiltration Testing Field Data NRCS Site Soil Mapping Branch Engineering, Inc. anch GINEERIM R11¢1: 287Dnamond'a Pen, Rd Tes3in8lx tz 26Ct5l OI/04/d1] 6E1Pmjett tt.-t Test TYPe: E¢uufil Fallia8lleadl¢IDVatw¢ 'lame' o at aamlm¢ of x2o WDVatim Tesll Tiudl FIa lLnel DepN to Walet SMace(U Depth of Watrr Rate Of Fa It. -Fa of Fall T -I. Standss Diamete 6 a 25.5 22.5 Stand ,Hei [ACS.1 5 29 28.0 20.0 0.11 65 Tett De h0G5 m 43 60 3t.0 l].0 0.08 9.9 VNume of Watet Atltletl 2 98 33.5 145 0.07 3.9 Cl -r ,at S 11:07 120 34.5 13.5 0-05 22 42 AS1bI5o0 180 37 11.0 Om 2.5 4.1 Infiloatim Tesl l Tt1al 2 ElapsedDepth Time (miW to Weter Snrface(iN DepN of Wates Rateaf Fell ft) (to/tool) ReteO FeLL (in A Rate of Fa111w VOWme Of Water Added l 0 32.0 16.0 C'..", 1410 20 33.0 LSO 0.05 3-0 50 34.0 190 0.03 20 ]] 33.5 125 006 3.3 2.8 Infilteaxao T.Hl Trial 3 Fleps Ilme(min) Delnhlo Water 5mfoce DepNof Water Rate Of Pall lto/mit) Rateof Rall (ioN) A Rateaf FallT3(ia r) VolOme of Water Added 03 0 320 16.0 Clacktlme 15'28 30 33.. 5 I<5 005 30 60 I 34.3 13.3 0.03 2.0 .5 'o o ro m Pale ofRafe of Water�ael Fall m/minFall m/min r Im.^ mo .m vo per®mentled Acle 4n/hr1-------------------- Nfiloadm Ten 2Tia11 Elapsed 11me 1 DepNtO Water Sm1ace llnl DepNof Water ..fFall (in) Ow.,i Rate Of Pall (IWIr) A Rate NFall T1' Slmd elfiametu 6 0 26.5 215 Stand Hei IAG3m S 15 28.0 200 0.10 60 Tea De 43 35 29.5 18.5 0.08 4.5 VW=e N Watu AWed al 1 60 31.0 120 0.06 3.6 Clnfklime 1210 90 It.0 15.0 0.07 4,0 42 ASIlLSWT a 120 34.5 13.5 005 3.0 In ration Teo 2 Tt t2 EUpsetl Time (min) IMONNWate} Soe-fio.) DepNOf Wolel Rate Of Fell lid (wmio) Role Of raA Im A4'GAate Of Fall T-2 ./ht) Wo -L. elec Atlded aI 0 290 19.0 ClOcktwe 14'10 20 30.0 18.0 0.05 3.0 50 320 16.0 0.07 40 1 335 14.5 0.06 3.6 35 Wiltratim Teet2Ttla13 Rlap9rd llolel� OeplM1 (u WvM Smfare (bt Depth of Walu BaIOOfo Mnl Ira ) Ratio Of Pap hl AVG RaN of Pell T-2' Wlnme of Water Added al QS 0 30.0 18.0 ClOrktlme1 1525 1 1 30 1 320 IGO 001 1 40 fi0 335 143 005 1 3. 3.5 ------------ ---------------------------------- g Pate of Water Fall folmint �. sm peio®mended Rate (in/he) 9G°9YN W 9PN Soil Map Lane County Area, Oregon @ (Oeadmond Ferry Rd) d � T 3 Map^ : 1:6751FRived m App (&Tx 11")? Y. NMm 9 0 10 m 40So A p w an 1® MryP :NIL Fbmtu opnami3�Me.: WG581 filgeba:NMZanelmN LRtb1 Natural Reaaurc . Web Soil Survey 12!11/2020 �i Coneervetio. Service National Cooperative Soil Survey Page 1 of 3 _ E /\ a_E!}E ;-sa, !{ (L ;s / °�{ 44)/t `(® I -{\ !) >• \\!\ !; )_!!;/)\)];q; ; ,-s»` ( /I� ■ § )g| �.10)KX ,0 dcoo >+x,-aw E Soil Map—Lane County Area, Oregon Map Unit Legend Daadmond Ferry Rd Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 75 Malahon silty clay loam 2.4 100.0% Totals for Area of Interest 2.4' 100.0% Natural Resources Web Soil Survey 12/11/2020 Conservation Service National Cooperative Soil Survey Page 3 of 3 Map Unit Description: Malabon silty clay loam --Lane County lvea, Oregon Lane County Area, Oregon 75—Malabon silty clay loam Map Unit Setting National map unit symbol: 238s Elevation: 300 to 650 feet Mean annual precipitation: 40 to 60 inches Mean annual air temperature: 52 to 54 degrees F Frost -free period. 165 to 210 days Farmland classification: All areas are prime farmland Map Unit Composition Malabon and similar soils: 90 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Malabon Setting Landform.: Terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across -slope shape: Linear Parent material., Silty and clayey alluvium Typical profile H1 - 0 to 12 inches: silty clay loam H2 - 12 to 42 inches: silty clay H3 - 42 to 50 inches: clay loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 inihr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of pending: None Available water capacity: High (about 11.4 inches) Interpretive groups Land capability classification (irrigated), 1 Land capability classification (nonirrigated): 1 Hydrologic Soil Group: C Forage suitability group: Well drained < 15% Slopes (GO02XY0020R) Other vegetative classification: Well drained < 15% Slopes (GO02XY0020R) Deadmond Ferry Rd Natural Resources Web soil Survey 12nl1zu2u Conservation service National Cooperative Soil Survey Page 1 of 2 Map Unit Description: Malabon silty clay loam—Lane County Area, Oregon Hydric soil rating: No Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 17, Jun 11, 2020 DeaAmond Ferry Rd mtm Natural Resources Web Soil Survey 121112020 Conservation Service National Cooperative Soil Survey Page 2 of 2 SCALE: (IVxl7') branch SITE EXPLOR ENGINEERING_ ATiO steewn SPRINGFIELD, OREGON 310 5th STREET, SPRING FIELD, OREGON 97477 ED �\ 1T-1 APPROXIMATE J LOCATION OF INFILTRATION TESTING 2-19-2021