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HomeMy WebLinkAboutWPO202000032 Calculations 2020-10-26SHIMP ENGINEERING, P.C. Design Focused Engineering October 22, 2020 County of Albemarle Department of Community Development 401 McIntire Road Charlottesville, VA 22902 Regarding: 1300 Richmond Road — Flow Automotive WP0202000032 Stormwater Management Plan Dear Reviewer, Lic. The purpose of this project is to make improvements to a site with existing automobile services and sales. The two existing buildings will be expanded upon, and one new sales building will be constructed. The total area of disturbance is 4.62 acres. Runoff from the site is analyzed at five points, labeled POA1 thru POA5. Please see VSMP plan sheets C12 and C13 for the locations of these drainage areas and points of analysis. The drainage areas to points of analysis 1 thru 3 are separated into disturbed and undisturbed area, since the improvement factor is only applied to the disturbed portions. Points of analysis 4 and 5 include only disturbed area, since the disturbances create no change to the drainage patterns outside the limits of disturbance in those areas. Drainage areas to POA 1 are further separated into drainage to the existing detention system on site and drainage straight to PDA 1. All end up at PDA 1, but this separation was used to ensure that the existing detention system will continue to function as designed. The post -development drainage area acreage and curve number to the existing detention system are less than in pre -development conditions. Runoff to POA 1 is held in a detention pond and released at a peak flow rate that complies with channel protection requirements set forth in 9VAC25-870-66-B3 (energy balance equation). Flood protection is met as runoff is outlet into a mapped floodplain. Runoff to all other points of analysis complies with channel protection requirements and flood protection requirements as the post -development 10 yr, 24 hr storm is released at a peak flow rate less than in pre - development conditions and the energy balance equation is satisfied. Please note that runoff in POA 5 was analyzed using 9VAC25-870-66-Bla as it is released to an adequate manmade channel and does not cause erosion. An excerpt from the previously approved stormwater plan calculations for Pantops Corner WP0201800088 is included showing downstream channel adequacy. Please see below for a summary of energy balance calculations. The first table shows 1 yr, 24 hr storm peak flow rates and runoff volume for drainage areas within the disturbed area. The improvement factor of 0.8 is applied to these values in the energy balance equation. The second table shows all values for drainage areas outside of the limits of disturbance, no improvement factor was applied to these values. The third table shows the final results, along with 10 yr, 24 hr storm peak flow rates of both pre and post development conditions. For further detail on these drainage areas and calculations, please see the HydroCAD reports included in this document. 912 E. High 5t. Charlottesville, VA 229021434.227.51401 shimp-engineering.com Table 1 Values for DAs Within LOD EnergX Balance Equation PREDEV POSTDEV POA Q1 RV RV 1 8.92 0.407 0.636 2 0.32 0.02 0.006 3 1.37 0.068 0.024 4 1.11 0.052 0.004 5 1.33 0.060 0.056 Table 2. Values for DAs Outside LOD — Enerc PREDEV POSTDEV POA Q1 RV RV 1 4.96 0.235 0.272 2 0.56 0.036 0.023 3 6.11 0.285 0.315 4 N/A N/A N/A 5 N/A N/A N/A ly Balance Equation Table 3. Summary of Results — Energy Balance Equation & Flood Protection /—Table 1 Table 2 Q1Allowable=(Q1Pre(LOD)*RVPre(LOD)*I.F./RvPost(LOD)]-+q[(Q1Pre*RvPre/RvPostl POA Q1 ALLOWABLE (cfs) Q1 PROPOSED (cfs) Q10 PRE (cfs) Q10 POST (cfs) 1 8.85 3.49 27.97 36.31* 2 1.73 0.49 7.29 3.74* 3 8.63 6.92 14.39 12.91 4 11.54 0.09 2.12 0.38 5 NA 1.22 2.67 2.41 *Discharges to Mapped Floodplain According to the VRRM spreadsheet included in this packet, the target phosphorus load reduction is 2.59 lb/yr. Nutrient credits will be purchased to satisfy this requirement. Contents: Pre -Development Stormwater Management Calculations: Pre -Development Landuse Map Pre -Development HydroCAD Analysis Post -Development Stormwater Management Calculations: Post -Development Landuse Map Post -Development HydroCAD Analysis Excerpt from WPO201800088 SWM Calculations for POA 5 Stormwater Quality Calculations: VRRM Redevelopment Spreadsheet Nutrient Credit Letter of Availability Independent Reports: Excerpt from NRCS Soils Report NOAA Precipitation Report Pre -Development Stormwater Management Calculations Pre -Development Landuse Map Pre -Development HydroCAD Analysis ; 14 1 � PRE -DEVELOPMENT LANDUSE MAP 1300 RICHMOND ROAD To Ex. Det. & POA LOD) 2S To Ex. Det. POA1 (Outside OD) C 3L To P Al Direct (IN LOD) POA 1 (WITHIN LOD) S4 Reach Aon Llnk To POA 1 Direct (Outside LOD) PreDev - POA 1 Prepared by {enter your company name here} PreDev - POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 5/29/2020 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To Ex. Det. & POA1 (IN Runoff Area=0.874 ac 89.02% Impervious Runoff Depth>2.42" Tc=5.0 min CN=96 Runoff=3.65 cfs 0.176 of Subcatchment2S: To Ex. Det. & POA1 Runoff Area=1.198 ac 88.98% Impervious Runoff Depth>2.32" Tc=5.0 min CN=95 Runoff=4.89 cfs 0.232 of Subcatchment4S: To POA 1 Direct (IN LOD)Runoff Area=1.615 ac 66.44% Impervious Runoff Depth>1.71" Tc=5.0 min CN=88 Runoff=5.27 cfs 0.231 of Subcatchment5S: To POA 1 Direct (Outside Runoff Area=0.068 ac 4.41% Impervious Runoff Depth>0.53" Tc=5.0 min CN=67 Runoff=0.07 cfs 0.003 of Link 3L: POA 1 (WITHIN LOD) Inflow=13.88 cfs 0.642 of Primary=13.88 cfs 0.642 of Total Runoff Area = 3.755 ac Runoff Volume = 0.642 of Average Runoff Depth = 2.05" 22.24% Pervious = 0.835 ac 77.76% Impervious = 2.920 ac PreDev - POA 1 Prepared by (enter your company name here} PreDev - POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 5/29/2020 Summary for Subcatchment 1S: To Ex. Det. & POM (IN LOD) Runoff = 3.65 cfs @ 11.95 hrs, Volume= 0.176 af, Depth> 2.42" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.003 61 >75% Grass cover, Good, HSG B * 0.079 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.093 80 >75% Grass cover, Good, HSG D * 0.699 98 Impervious, HSG D 0.874 96 Weighted Average 0.096 10.98% Pervious Area 0.778 89.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: To Ex. Det. & POM (Outside LOD) Runoff = 4.89 cfs @ 11.95 hrs, Volume= 0.232 af, Depth> 2.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.065 61 >75% Grass cover, Good, HSG B * 0.688 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.067 80 >75% Grass cover, Good, HSG D * 0.378 98 Impervious, HSG D 1.198 95 Weighted Average 0.132 11.02% Pervious Area 1.066 88.98% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PreDev - POA 1 Prepared by (enter your company name here} PreDev - POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 5/29/2020 Summary for Subcatchment 4S: To POA 1 Direct (IN LOD) Runoff = 5.27 cfs @ 11.96 hrs, Volume= 0.231 af, Depth> 1.71" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.062 58 Woods/grass comb., Good, HSG B 0.295 61 >75% Grass cover, Good, HSG B * 0.691 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.185 80 >75% Grass cover, Good, HSG D * 0.382 98 Impervious, HSG D 1.615 88 Weighted Average 0.542 33.56% Pervious Area 1.073 66.44% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: To POA 1 Direct (Outside LOD) Runoff = 0.07 cfs @ 11.98 hrs, Volume= 0.003 af, Depth> 0.53" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.042 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.023 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.003 98 Impervious, HSG D 0.068 67 Weighted Average 0.065 95.59% Pervious Area 0.003 4.41% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PreDev - POA 1 Prepared by {enter your company name here} PreDev - POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 5/29/2020 Summary for Link 3L: POA 1 (WITHIN LOD) Inflow Area = 3.755 ac, 77.76% Impervious, Inflow Depth > 2.05" for 1 yr, 24 hr event Inflow = 13.88 cfs @ 11.95 hrs, Volume= 0.642 of Primary = 13.88 cfs @ 11.95 hrs, Volume= 0.642 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PreDev - POA 1 PreDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by {enter your company name here} Printed 5/29/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 6 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To Ex. Det. & POA1 (IN Runoff Area=0.874 ac 89.02% Impervious Runoff Depth>4.70" Tc=5.0 min CN=96 Runoff=6.89 cfs 0.343 of Subcatchment2S: To Ex. Det. & POA1 Runoff Area=1.198 ac 88.98% Impervious Runoff Depth>4.61" Tc=5.0 min CN=95 Runoff=9.36 cfs 0.461 of Subcatchment4S: To POA 1 Direct (IN LOD)Runoff Area=1.615 ac 66.44% Impervious Runoff Depth>3.92" Tc=5.0 min CN=88 Runoff=11.45 cfs 0.528 of Subcatchment5S: To POA 1 Direct (Outside Runoff Area=0.068 ac 4.41% Impervious Runoff Depth>1.99" Tc=5.0 min CN=67 Runoff=0.27 cfs 0.011 of Link 3L: POA 1 (WITHIN LOD) Inflow=27.97 cfs 1.343 of Primary=27.97 cfs 1.343 of Total Runoff Area = 3.755 ac Runoff Volume = 1.343 of Average Runoff Depth = 4.29" 22.24% Pervious = 0.835 ac 77.76% Impervious = 2.920 ac PreDev - POA 1 PreDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by (enter your company name here} Printed 5/29/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 7 Summary for Subcatchment 1S: To Ex. Det. & POA1 (IN LOD) Runoff = 6.89 cfs @ 11.95 hrs, Volume= 0.343 af, Depth> 4.70" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.003 61 >75% Grass cover, Good, HSG B * 0.079 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.093 80 >75% Grass cover, Good, HSG D * 0.699 98 Impervious, HSG D 0.874 96 Weighted Average 0.096 10.98% Pervious Area 0.778 89.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: To Ex. Det. & POA1 (Outside LOD) Runoff = 9.36 cfs @ 11.95 hrs, Volume= 0.461 af, Depth> 4.61" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.065 61 >75% Grass cover, Good, HSG B * 0.688 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.067 80 >75% Grass cover, Good, HSG D * 0.378 98 Impervious, HSG D 1.198 95 Weighted Average 0.132 11.02% Pervious Area 1.066 88.98% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PreDev - POA 1 PreDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by (enter your company name here} Printed 5/29/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 8 Summary for Subcatchment 4S: To POA 1 Direct (IN LOD) Runoff = 11.45 cfs @ 11.95 hrs, Volume= 0.528 af, Depth> 3.92" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.062 58 Woods/grass comb., Good, HSG B 0.295 61 >75% Grass cover, Good, HSG B * 0.691 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.185 80 >75% Grass cover, Good, HSG D * 0.382 98 Impervious, HSG D 1.615 88 Weighted Average 0.542 33.56% Pervious Area 1.073 66.44% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: To POA 1 Direct (Outside LOD) Runoff = 0.27 cfs @ 11.96 hrs, Volume= 0.011 af, Depth> 1.99" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.042 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.023 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.003 98 Impervious, HSG D 0.068 67 Weighted Average 0.065 95.59% Pervious Area 0.003 4.41% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PreDev - POA 1 PreDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by {enter your company name here} Printed 5/29/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 9 Summary for Link 3L: POA 1 (WITHIN LOD) Inflow Area = 3.755 ac, 77.76% Impervious, Inflow Depth > 4.29" for 10 yr, 24 hr event Inflow = 27.97 cfs @ 11.95 hrs, Volume= 1.343 of Primary = 27.97 cfs @ 11.95 hrs, Volume= 1.343 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs 1S 2S To POA 2 (IN OD) To P A 2 (Outside LOD) 3L PDA 2 To POA 4 (IN OD) S POA 4 S4 Reach Aon Llnk 4S 5S To POA 3 (1 OD) To POA 3 (Outside LOD) 4L POA 3 9S To POA 5 (IN L D) 12L POA 5 PreDev Prepared by {enter your company name here} PreDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To POA 2 (IN LOD) Runoff Area=1.020 ac 0.00% Impervious Runoff Depth>0.24" Tc=5.0 min CN=58 Runoff=0.32 cfs 0.020 of Subcatchment2S: To POA 2 (Outside LOD) Runoff Area=1.820 ac 0.00% Impervious Runoff Depth>0.24" Tc=5.0 min CN=58 Runoff=0.56 cfs 0.036 of Subcatchment4S: To POA 3 (IN LOD) Runoff Area=0.316 ac 100.00% Impervious Runoff Depth>2.59" Tc=5.0 min CN=98 Runoff=1.37 cfs 0.068 of Subcatchment5S: To PDA 3 (Outside LOD) Runoff Area=1.534 ac 89.50% Impervious Runoff Depth>2.23" Tc=5.0 min CN=94 Runoff=6.11 cfs 0.285 of Subcatchment7S: To POA 4 (IN LOD) Runoff Area=0.271 ac 92.99% Impervious Runoff Depth>2.32" Tc=5.0 min CN=95 Runoff=1.11 cfs 0.052 of Subcatchment9S: To POA 5 (IN LOD) Runoff Area=0.354 ac 65.54% Impervious Runoff Depth>2.05" Tc=5.0 min CN=92 Runoff=1.33 cfs 0.060 of Link 3L: POA 2 Inflow=0.88 cfs 0.056 of Primary=0.88 cfs 0.056 of Link 4L: POA 3 Inflow=7.47 cfs 0.354 of Primary=7.47 cfs 0.354 of Link 11 L: POA 4 Inflow=1.11 cfs 0.052 of Primary=1.11 cfs 0.052 of Link 12L: POA 5 Inflow=1.33 cfs 0.060 of Primary=1.33 cfs 0.060 of Total Runoff Area = 5.315 ac Runoff Volume = 0.523 of Average Runoff Depth = 1.18" 59.12% Pervious = 3.142 ac 40.88% Impervious = 2.173 ac PreDev Prepared by {enter your company name here} PreDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Summary for Subcatchment 1S: To POA 2 (IN LOD) Runoff = 0.32 cfs @ 12.00 hrs, Volume= 0.020 af, Depth> 0.24" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Descriotion 1.020 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 1.020 58 Weighted Average 1.020 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (f /ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: To POA 2 (Outside LOD) Runoff = 0.56 cfs @ 12.00 hrs, Volume= 0.036 af, Depth> 0.24" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Descriotion 1.820 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 1.820 58 Weighted Average 1.820 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: To POA 3 (IN LOD) Runoff = 1.37 cfs @ 11.95 hrs, Volume= 0.068 af, Depth> 2.59" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" PreDev Prepared by {enter your company name here} Area (ac) CN Description PreDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.102 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.214 98 Impervious. HSG D 0.316 98 Weighted Average 0.316 100.00% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Runoff = Direct Entry, Summary for Subcatchment SS: To POA 3 (Outside LOD) 6.11 cfs @ 11.95 hrs, Volume= 0.285 af, Depth> 2.23" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN 0.000 58 Woods/grass comb., Good, HSG B 0.161 61 >75% Grass cover, Good, HSG B 0.702 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.671 98 Impervious, HSG D 1.534 94 Weighted Average 0.161 10.50% Pervious Area 1.373 89.50% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To POA 4 (IN LOD) Runoff = 1.11 cfs @ 11.95 hrs, Volume= 0.052 af, Depth> 2.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" PreDev Prepared by {enter your company name here} Area (ac) CN Description PreDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.019 61 >75% Grass cover, Good, HSG B 0.252 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.000 98 Impervious. HSG D 0.271 95 Weighted Average 0.019 7.01 % Pervious Area 0.252 92.99% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 5 (IN LOD) Runoff = 1.33 cfs @ 11.95 hrs, Volume= 0.060 af, Depth> 2.05" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.122 80 >75% Grass cover, Good, HSG D 0.232 98 Impervious. HSG D 0.354 92 Weighted Average 0.122 34.46% Pervious Area 0.232 65.54% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 3L: PDA 2 Inflow Area = 2.840 ac, 0.00% Impervious, Inflow Depth > 0.24" for 1 yr, 24 hr event Inflow = 0.88 cfs @ 12.00 hrs, Volume= 0.056 of Primary = 0.88 cfs @ 12.00 hrs, Volume= 0.056 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PreDev Prepared by {enter your company name here} PreDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Summary for Link 4L: POA 3 Inflow Area = 1.850 ac, 91.30% Impervious, Inflow Depth > 2.29" for 1 yr, 24 hr event Inflow = 7.47 cfs @ 11.95 hrs, Volume= 0.354 of Primary = 7.47 cfs @ 11.95 hrs, Volume= 0.354 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 11L: POA 4 Inflow Area = 0.271 ac, 92.99% Impervious, Inflow Depth > 2.32" for 1 yr, 24 hr event Inflow = 1.11 cfs @ 11.95 hrs, Volume= 0.052 of Primary = 1.11 cfs @ 11.95 hrs, Volume= 0.052 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 12L: POA 5 Inflow Area = 0.354 ac, 65.54% Impervious, Inflow Depth > 2.05" for 1 yr, 24 hr event Inflow = 1.33 cfs @ 11.95 hrs, Volume= 0.060 of Primary = 1.33 cfs @ 11.95 hrs, Volume= 0.060 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PreDev Prepared by {enter your company name here} PreDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To POA 2 (IN LOD) Runoff Area=1.020 ac 0.00% Impervious Runoff Depth>1.32" Tc=5.0 min CN=58 Runoff=2.62 cfs 0.112 of Subcatchment2S: To POA 2 (Outside LOD) Runoff Area=1.820 ac 0.00% Impervious Runoff Depth>1.32" Tc=5.0 min CN=58 Runoff=4.67 cfs 0.200 of Subcatchment4S: To POA 3 (IN LOD) Runoff Area=0.316 ac 100.00% Impervious Runoff Depth>4.86" Tc=5.0 min CN=98 Runoff=2.52 cfs 0.128 of Subcatchment5S: To PDA 3 (Outside LOD) Runoff Area=1.534 ac 89.50% Impervious Runoff Depth>4.52" Tc=5.0 min CN=94 Runoff=11.87 cfs 0.578 of Subcatchment7S: To POA 4 (IN LOD) Runoff Area=0.271 ac 92.99% Impervious Runoff Depth>4.61" Tc=5.0 min CN=95 Runoff=2.12 cfs 0.104 of Subcatchment9S: To POA 5 (IN LOD) Runoff Area=0.354 ac 65.54% Impervious Runoff Depth>4.33" Tc=5.0 min CN=92 Runoff=2.67 cfs 0.128 of Link 3L: POA 2 Inflow=7.29 cfs 0.312 of Primary=7.29 cfs 0.312 of Link 4L: POA 3 Inflow=14.39 cfs 0.706 of Primary=14.39 cfs 0.706 of Link 11 L: POA 4 Inflow=2.12 cfs 0.104 of Primary=2.12 cfs 0.104 of Link 12L: POA 5 Inflow=2.67 cfs 0.128 of Primary=2.67 cfs 0.128 of Total Runoff Area = 5.315 ac Runoff Volume = 1.250 of Average Runoff Depth = 2.82" 59.12% Pervious = 3.142 ac 40.88% Impervious = 2.173 ac PreDev Prepared by {enter your company name here} PreDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 Summary for Subcatchment 1S: To POA 2 (IN LOD) Runoff = 2.62 cfs @ 11.97 hrs, Volume= 0.112 af, Depth> 1.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Descriotion 1.020 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 1.020 58 Weighted Average 1.020 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (f /ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: To POA 2 (Outside LOD) Runoff = 4.67 cfs @ 11.97 hrs, Volume= 0.200 af, Depth> 1.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Descriotion 1.820 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 1.820 58 Weighted Average 1.820 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: To POA 3 (IN LOD) Runoff = 2.52 cfs @ 11.95 hrs, Volume= 0.128 af, Depth> 4.86" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" PreDev Prepared by {enter your company name here} Area (ac) CN Description PreDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.102 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.214 98 Impervious. HSG D 0.316 98 Weighted Average 0.316 100.00% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Runoff = Direct Entry, Summary for Subcatchment 5S: To POA 3 (Outside LOD) 11.87 cfs @ 11.95 hrs, Volume= 0.578 af, Depth> 4.52" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN 0.000 58 Woods/grass comb., Good, HSG B 0.161 61 >75% Grass cover, Good, HSG B 0.702 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.671 98 Impervious, HSG D 1.534 94 Weighted Average 0.161 10.50% Pervious Area 1.373 89.50% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To POA 4 (IN LOD) Runoff = 2.12 cfs @ 11.95 hrs, Volume= 0.104 af, Depth> 4.61" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" PreDev Prepared by {enter your company name here} Area (ac) CN Description PreDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.019 61 >75% Grass cover, Good, HSG B 0.252 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.000 98 Impervious. HSG D 0.271 95 Weighted Average 0.019 7.01 % Pervious Area 0.252 92.99% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 5 (IN LOD) Runoff = 2.67 cfs @ 11.95 hrs, Volume= 0.128 af, Depth> 4.33" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.122 80 >75% Grass cover, Good, HSG D 0.232 98 Impervious. HSG D 0.354 92 Weighted Average 0.122 34.46% Pervious Area 0.232 65.54% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 3L: PDA 2 Inflow Area = 2.840 ac, 0.00% Impervious, Inflow Depth > 1.32" for 10 yr, 24 hr event Inflow = 7.29 cfs @ 11.97 hrs, Volume= 0.312 of Primary = 7.29 cfs @ 11.97 hrs, Volume= 0.312 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PreDev Prepared by {enter your company name here} PreDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 Summary for Link 4L: POA 3 Inflow Area = 1.850 ac, 91.30% Impervious, Inflow Depth > 4.58" for 10 yr, 24 hr event Inflow = 14.39 cfs @ 11.95 hrs, Volume= 0.706 of Primary = 14.39 cfs @ 11.95 hrs, Volume= 0.706 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 11L: POA 4 Inflow Area = 0.271 ac, 92.99% Impervious, Inflow Depth > 4.61" for 10 yr, 24 hr event Inflow = 2.12 cfs @ 11.95 hrs, Volume= 0.104 of Primary = 2.12 cfs @ 11.95 hrs, Volume= 0.104 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 12L: POA 5 Inflow Area = 0.354 ac, 65.54% Impervious, Inflow Depth > 4.33" for 10 yr, 24 hr event Inflow = 2.67 cfs @ 11.95 hrs, Volume= 0.128 of Primary = 2.67 cfs @ 11.95 hrs, Volume= 0.128 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Post -Development Stormwater Management Calculations Post -Development Landuse Map Post -Development HydroCAD Analysis Excerpt from WPO201800088 SWM Calculations for POA 5 ; a I � POST -DEVELOPMENT LANDUSE MAP RICHMOND (is 7S 8S �9S j o Ex. Det. & POA 1 To Ex. Det. & OA 1 To PO 1 Directly (IN o POA 1 Directly LOD) (Outside L ) LOD) (Outside LOD) 7P Detention Pond Test POA 1 S4 Reach Aon Llnk PostDev - POA 1 Prepared by {enter your company name here} PostDev POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Time span=0.00-48.00 hrs, dt=0.05 hrs, 961 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To Ex. Det. & POA 1 (IN Runoff Area=0.571 ac 97.72% Impervious Runoff Depth=2.80" Tc=5.0 min CN=98 Runoff=2.47 cfs 0.133 of Subcatchment7S: To Ex. Det. & POA 1 Runoff Area=1.238 ac 87.56% Impervious Runoff Depth=2.48" Tc=5.0 min CN=95 Runoff=5.06 cfs 0.256 of Subcatchment8S: To POA 1 Directly (IN Runoff Area=3.130 ac 71.47% Impervious Runoff Depth=1.93" Tc=5.0 min CN=89 Runoff=10.61 cfs 0.503 of Subcatchment9S: To POA 1 Directly Runoff Area=0.692 ac 0.00% Impervious Runoff Depth=0.28" Tc=5.0 min CN=58 Runoff=0.21 cfs 0.016 of Pond 7P: Detention Pond Test Peak Elev=344.65' Storage=13,619 cf Inflow=-18.28 cfs 0.908 of Outflow=3.49 cfs 0.908 of Link 6L: POA 1 Inflow=3.49 cfs 0.908 of Primary=3.49 cfs 0.908 of Total Runoff Area = 5.631 ac Runoff Volume = 0.908 of Average Runoff Depth = 1.93" 31.11% Pervious = 1.752 ac 68.89% Impervious = 3.879 ac PostDev - POA 1 Prepared by (enter your company name here} PostDev POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Summary for Subcatchment 1S: To Ex. Det. & POA 1 (IN LOD) Runoff = 2.47 cfs @ 11.95 hrs, Volume= 0.133 af, Depth= 2.80" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.002 61 >75% Grass cover, Good, HSG B * 0.058 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.011 80 >75% Grass cover, Good, HSG D * 0.500 98 Impervious, HSG D 0.571 98 Weighted Average 0.013 2.28% Pervious Area 0.558 97.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To Ex. Det. & POA 1 (Outside LOD) Runoff = 5.06 cfs @ 11.95 hrs, Volume= 0.256 af, Depth= 2.48" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.066 61 >75% Grass cover, Good, HSG B * 0.684 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.088 80 >75% Grass cover, Good, HSG D * 0.400 98 Impervious, HSG D 1.238 95 Weighted Average 0.154 12.44% Pervious Area 1.084 87.56% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PostDev - PDA 1 Prepared by (enter your company name here} PostDev POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Summary for Subcatchment 8S: To POA 1 Directly (IN LOD) Runoff = 10.61 cfs @ 11.95 hrs, Volume= 0.503 af, Depth= 1.93" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.673 61 >75% Grass cover, Good, HSG B * 1.335 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.220 80 >75% Grass cover, Good, HSG D * 0.902 98 Impervious, HSG D 3.130 89 Weighted Average 0.893 28.53% Pervious Area 2.237 71.47% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 1 Directly (Outside LOD) Runoff = 0.21 cfs @ 12.00 hrs, Volume= 0.016 af, Depth= 0.28" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.645 58 Woods/grass comb., Good, HSG B 0.047 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 0.692 58 Weighted Average 0.692 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 7P: Detention Pond Test Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 1.93" for 1 yr, 24 hr event Inflow = 18.28 cfs @ 11.95 hrs, Volume= 0.908 of Outflow = 3.49 cfs @ 12.12 hrs, Volume= 0.908 af, Atten= 81 %, Lag= 10.2 min Primary = 3.49 cfs @ 12.12 hrs, Volume= 0.908 of PostDev - POA 1 Prepared by {enter your company name here} PostDev POA 1 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 344.65' @ 12.12 hrs Surf.Area= 4,361 sf Storage= 13,619 cf Plug -Flow detention time= 41.4 min calculated for 0.908 of (100% of inflow) Center -of -Mass det. time= 40.9 min (835.6 - 794.7) Volume Invert Avail.Storage Storage Description #1 340.00' 20,135 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 340.00 1,634 0 0 342.00 2,690 4,324 4,324 344.00 3,921 6,611 10,935 346.00 5,279 9,200 20,135 Device Routing Invert Outlet Devices #1 Primary 339.80' 30.0" Round Culvert L= 65.4' Ke= 0.600 Inlet / Outlet Invert= 339.80' / 339.21' S= 0.0090 '/' Cc= 0.900 n= 0.012 #2 Device 1 340.00' 8.0" Vert. Orifice/Grate C= 0.600 #3 Primary 344.66' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=3.49 cfs @ 12.12 hrs HW=344.63' (Free Discharge) �1=culvert (Passes 3.49 cfs of 41.95 cfs potential flow) t2=Orifice/Grate (Orifice Controls 3.49 cfs @ 9.98 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) Summary for Link 6L: POA 1 Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 1.93" for 1 yr, 24 hr event Inflow = 3.49 cfs @ 12.12 hrs, Volume= 0.908 of Primary = 3.49 cfs @ 12.12 hrs, Volume= 0.908 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs PostDev - POA 1 Prepared by {enter your company name here} PostDev POA 1 Type 11 24-hr 2 yr, 24 hr Rainfall=3.66" Printed 7/15/2020 Time span=0.00-48.00 hrs, dt=0.05 hrs, 961 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To Ex. Det. & POA 1 (IN Runoff Area=0.571 ac 97.72% Impervious Runoff Depth=3.43" Tc=5.0 min CN=98 Runoff=2.99 cfs 0.163 of Subcatchment7S: To Ex. Det. & POA 1 Runoff Area=1.238 ac 87.56% Impervious Runoff Depth=3.10" Tc=5.0 min CN=95 Runoff=6.23 cfs 0.319 of Subcatchment8S: To POA 1 Directly (IN Runoff Area=3.130 ac 71.47% Impervious Runoff Depth=2.51" Tc=5.0 min CN=89 Runoff=13.62 cfs 0.654 of Subcatchment9S: To POA 1 Directly Runoff Area=0.692 ac 0.00% Impervious Runoff Depth=0.52" Tc=5.0 min CN=58 Runoff=0.52 cfs 0.030 of Pond 7P: Detention Pond Test Peak Elev=345.06' Storage=15,466 cf Inflow=23.30 cfs 1.166 of Outflow=14.01 cfs 1.166 of Link 6L: POA 1 Inflow=14.01 cfs 1.166 of Primary=14.01 cfs 1.166 of Total Runoff Area = 5.631 ac Runoff Volume = 1.166 of Average Runoff Depth = 2.48" 31.11% Pervious = 1.752 ac 68.89% Impervious = 3.879 ac PostDev - POA 1 Prepared by (enter your company name here} PostDev POA 1 Type 11 24-hr 2 yr, 24 hr Rainfall=3.66" Printed 7/15/2020 Summary for Subcatchment 1S: To Ex. Det. & POA 1 (IN LOD) Runoff = 2.99 cfs @ 11.95 hrs, Volume= 0.163 af, Depth= 3.43" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr, 24 hr Rainfall=3.66" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.002 61 >75% Grass cover, Good, HSG B * 0.058 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.011 80 >75% Grass cover, Good, HSG D * 0.500 98 Impervious, HSG D 0.571 98 Weighted Average 0.013 2.28% Pervious Area 0.558 97.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To Ex. Det. & POA 1 (Outside LOD) Runoff = 6.23 cfs @ 11.95 hrs, Volume= 0.319 af, Depth= 3.10" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr, 24 hr Rainfall=3.66" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.066 61 >75% Grass cover, Good, HSG B * 0.684 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.088 80 >75% Grass cover, Good, HSG D * 0.400 98 Impervious, HSG D 1.238 95 Weighted Average 0.154 12.44% Pervious Area 1.084 87.56% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PostDev - PDA 1 Prepared by (enter your company name here} PostDev POA 1 Type 11 24-hr 2 yr, 24 hr Rainfall=3.66" Printed 7/15/2020 Summary for Subcatchment 8S: To POA 1 Directly (IN LOD) Runoff = 13.62 cfs @ 11.95 hrs, Volume= 0.654 af, Depth= 2.51" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr, 24 hr Rainfall=3.66" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.673 61 >75% Grass cover, Good, HSG B * 1.335 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.220 80 >75% Grass cover, Good, HSG D * 0.902 98 Impervious, HSG D 3.130 89 Weighted Average 0.893 28.53% Pervious Area 2.237 71.47% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 1 Directly (Outside LOD) Runoff = 0.52 cfs @ 11.99 hrs, Volume= 0.030 af, Depth= 0.52" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr, 24 hr Rainfall=3.66" Area (ac) CN Description 0.645 58 Woods/grass comb., Good, HSG B 0.047 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 0.692 58 Weighted Average 0.692 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 7P: Detention Pond Test Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 2.48" for 2 yr, 24 hr event Inflow = 23.30 cfs @ 11.95 hrs, Volume= 1.166 of Outflow = 14.01 cfs @ 12.05 hrs, Volume= 1.166 af, Atten= 40%, Lag= 5.9 min Primary = 14.01 cfs @ 12.05 hrs, Volume= 1.166 of PostDev - POA 1 Prepared by {enter your company name here} PostDev POA 1 Type 11 24-hr 2 yr, 24 hr Rainfall=3.66" Printed 7/15/2020 Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 345.06' @ 12.05 hrs Surf.Area= 4,640 sf Storage= 15,466 cf Plug -Flow detention time= 37.3 min calculated for 1.165 of (100% of inflow) Center -of -Mass det. time= 37.6 min (826.7 - 789.2 ) Volume Invert Avail.Storage Storage Description #1 340.00' 20,135 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 340.00 1,634 0 0 342.00 2,690 4,324 4,324 344.00 3,921 6,611 10,935 346.00 5,279 9,200 20,135 Device Routing Invert Outlet Devices #1 Primary 339.80' 30.0" Round Culvert L= 65.4' Ke= 0.600 Inlet / Outlet Invert= 339.80' / 339.21' S= 0.0090 '/' Cc= 0.900 n= 0.012 #2 Device 1 340.00' 8.0" Vert. Orifice/Grate C= 0.600 #3 Primary 344.66' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=13.82 cfs @ 12.05 hrs HW=345.05' (Free Discharge) �1=Culvert (Passes 3.65 cfs of 44.34 cfs potential flow) t2=Orifice/Grate (Orifice Controls 3.65 cfs @ 10.46 fps) 3=Orif ice/G rate (Weir Controls 10.17 cfs @ 2.05 fps) Summary for Link 6L: POA 1 Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 2.48" for 2 yr, 24 hr event Inflow = 14.01 cfs @ 12.05 hrs, Volume= 1.166 of Primary = 14.01 cfs @ 12.05 hrs, Volume= 1.166 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs PostDev POA 1 PostDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by {enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 10 Time span=0.00-48.00 hrs, dt=0.05 hrs, 961 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To Ex. Det. & POA 1 (IN Runoff Area=0.571 ac 97.72% Impervious Runoff Depth=5.30" Tc=5.0 min CN=98 Runoff=4.56 cfs 0.252 of Subcatchment7S: To Ex. Det. & POA 1 Runoff Area=1.238 ac 87.56% Impervious Runoff Depth=4.95" Tc=5.0 min CN=95 Runoff=9.67 cfs 0.511 of Subcatchment8S: To POA 1 Directly (IN Runoff Area=3.130 ac 71.47% Impervious Runoff Depth=4.29" Tc=5.0 min CN=89 Runoff=22.58 cfs 1.119 of Subcatchment9S: To POA 1 Directly Runoff Area=0.692 ac 0.00% Impervious Runoff Depth=1.48" Tc=5.0 min CN=58 Runoff=1.78 cfs 0.085 of Pond 7P: Detention Pond Test Peak Elev=345.52' Storage=17,660 cf Inflow=38.55 cfs 1.968 of Outflow=36.31 cfs 1.968 of Link 6L: POA 1 Inflow=36.31 cfs 1.968 of Primary=36.31 cfs 1.968 of Total Runoff Area = 5.631 ac Runoff Volume = 1.968 of Average Runoff Depth = 4.19" 31.11% Pervious = 1.752 ac 68.89% Impervious = 3.879 ac PostDev POA 1 PostDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by (enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 11 Summary for Subcatchment 1S: To Ex. Det. & POA 1 (IN LOD) Runoff = 4.56 cfs @ 11.95 hrs, Volume= 0.252 af, Depth= 5.30" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.002 61 >75% Grass cover, Good, HSG B * 0.058 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.011 80 >75% Grass cover, Good, HSG D * 0.500 98 Impervious, HSG D 0.571 98 Weighted Average 0.013 2.28% Pervious Area 0.558 97.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To Ex. Det. & POA 1 (Outside LOD) Runoff = 9.67 cfs @ 11.95 hrs, Volume= 0.511 af, Depth= 4.95" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.066 61 >75% Grass cover, Good, HSG B * 0.684 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.088 80 >75% Grass cover, Good, HSG D * 0.400 98 Impervious, HSG D 1.238 95 Weighted Average 0.154 12.44% Pervious Area 1.084 87.56% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PostDev POA 1 PostDev - PDA 1 Type 1124-hr 10 yr, 24 hr Rainfall=5.54" Prepared by (enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 12 Summary for Subcatchment 8S: To POA 1 Directly (IN LOD) Runoff = 22.58 cfs @ 11.95 hrs, Volume= 1.119 af, Depth= 4.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.673 61 >75% Grass cover, Good, HSG B * 1.335 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.220 80 >75% Grass cover, Good, HSG D * 0.902 98 Impervious, HSG D 3.130 89 Weighted Average 0.893 28.53% Pervious Area 2.237 71.47% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 1 Directly (Outside LOD) Runoff = 1.78 cfs @ 11.97 hrs, Volume= 0.085 af, Depth= 1.48" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.645 58 Woods/grass comb., Good, HSG B 0.047 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 0.692 58 Weighted Average 0.692 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 7P: Detention Pond Test Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 4.19" for 10 yr, 24 hr event Inflow = 38.55 cfs @ 11.95 hrs, Volume= 1.968 of Outflow = 36.31 cfs @ 11.98 hrs, Volume= 1.968 af, Atten= 6%, Lag= 1.9 min Primary = 36.31 cfs @ 11.98 hrs, Volume= 1.968 of PostDev POA 1 PostDev - POA 1 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by {enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 13 Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 345.52' @ 11.98 hrs Surf.Area= 4,950 sf Storage= 17,660 cf Plug -Flow detention time= 31.1 min calculated for 1.968 of (100% of inflow) Center -of -Mass det. time= 30.5 min (808.3 - 777.8) Volume Invert Avail.Storage Storage Description #1 340.00' 20,135 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 340.00 1,634 0 0 342.00 2,690 4,324 4,324 344.00 3,921 6,611 10,935 346.00 5,279 9,200 20,135 Device Routing Invert Outlet Devices #1 Primary 339.80' 30.0" Round Culvert L= 65.4' Ke= 0.600 Inlet / Outlet Invert= 339.80' / 339.21' S= 0.0090 '/' Cc= 0.900 n= 0.012 #2 Device 1 340.00' 8.0" Vert. Orifice/Grate C= 0.600 #3 Primary 344.66' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=34.90 cfs @ 11.98 hrs HW=345.49' (Free Discharge) �1=Culvert (Passes 3.82 cfs of 46.69 cfs potential flow) t2=Orifice/Grate (Orifice Controls 3.82 cfs @ 10.93 fps) 3=Orif ice/G rate (Weir Controls 31.08 cfs @ 2.98 fps) Summary for Link 6L: POA 1 Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 4.19" for 10 yr, 24 hr event Inflow = 36.31 cfs @ 11.98 hrs, Volume= 1.968 of Primary = 36.31 cfs @ 11.98 hrs, Volume= 1.968 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs PostDev POA 1 PostDev - POA 1 Type 11 24-hr 100 yr, 24 hr Rainfall=9.10" Prepared by {enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 14 Time span=0.00-48.00 hrs, dt=0.05 hrs, 961 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To Ex. Det. & POA 1 (IN Runoff Area=0.571 ac 97.72% Impervious Runoff Depth=8.86" Tc=5.0 min CN=98 Runoff=7.50 cfs 0.422 of Subcatchment7S: To Ex. Det. & POA 1 Runoff Area=1.238 ac 87.56% Impervious Runoff Depth=8.50" Tc=5.0 min CN=95 Runoff=16.13 cfs 0.877 of Subcatchment8S: To POA 1 Directly (IN Runoff Area=3.130 ac 71.47% Impervious Runoff Depth=7.77" Tc=5.0 min CN=89 Runoff=39.32 cfs 2.026 of Subcatchment9S: To POA 1 Directly Runoff Area=0.692 ac 0.00% Impervious Runoff Depth=3.93" Tc=5.0 min CN=58 Runoff=4.90 cfs 0.227 of Pond 7P: Detention Pond Test Peak Elev=345.95' Storage=19,892 cf Inflow=67.82 cfs 3.551 of Outflow=64.38 cfs 3.551 of Link 6L: POA 1 Inflow=64.38 cfs 3.551 of Primary=64.38 cfs 3.551 of Total Runoff Area = 5.631 ac Runoff Volume = 3.551 of Average Runoff Depth = 7.57" 31.11% Pervious = 1.752 ac 68.89% Impervious = 3.879 ac PostDev POA 1 PostDev - POA 1 Type 11 24-hr 100 yr, 24 hr Rainfall=9.10" Prepared by (enter your company name here} Printed 7/15/2020 HvdroCAD@ 9.10 s/n 07054 @ 2011 HvdroCAD Software Solutions LLC Paae 15 Summary for Subcatchment 1S: To Ex. Det. & POA 1 (IN LOD) Runoff = 7.50 cfs @ 11.95 hrs, Volume= 0.422 af, Depth= 8.86" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.002 61 >75% Grass cover, Good, HSG B * 0.058 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.011 80 >75% Grass cover, Good, HSG D * 0.500 98 Impervious, HSG D 0.571 98 Weighted Average 0.013 2.28% Pervious Area 0.558 97.72% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To Ex. Det. & POA 1 (Outside LOD) Runoff = 16.13 cfs @ 11.95 hrs, Volume= 0.877 af, Depth= 8.50" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.066 61 >75% Grass cover, Good, HSG B * 0.684 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.088 80 >75% Grass cover, Good, HSG D * 0.400 98 Impervious, HSG D 1.238 95 Weighted Average 0.154 12.44% Pervious Area 1.084 87.56% Impervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, PostDev POA 1 PostDev - PDA 1 Type 1124-hr 100 yr, 24 hr Rainfall=9.10" Prepared by (enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 16 Summary for Subcatchment 8S: To POA 1 Directly (IN LOD) Runoff = 39.32 cfs @ 11.95 hrs, Volume= 2.026 af, Depth= 7.77" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.673 61 >75% Grass cover, Good, HSG B * 1.335 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.220 80 >75% Grass cover, Good, HSG D * 0.902 98 Impervious, HSG D 3.130 89 Weighted Average 0.893 28.53% Pervious Area 2.237 71.47% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (f /sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 1 Directly (Outside LOD) Runoff = 4.90 cfs @ 11.96 hrs, Volume= 0.227 af, Depth= 3.93" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 0.645 58 Woods/grass comb., Good, HSG B 0.047 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 0.692 58 Weighted Average 0.692 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 7P: Detention Pond Test Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 7.57" for 100 yr, 24 hr event Inflow = 67.82 cfs @ 11.95 hrs, Volume= 3.551 of Outflow = 64.38 cfs @ 11.97 hrs, Volume= 3.551 af, Atten= 5%, Lag= 1.3 min Primary = 64.38 cfs @ 11.97 hrs, Volume= 3.551 of PostDev POA 1 PostDev - POA 1 Type 11 24-hr 100 yr, 24 hr Rainfall=9.10" Prepared by {enter your company name here} Printed 7/15/2020 HvdroCAD® 9.10 s/n 07054 ©2011 HvdroCAD Software Solutions LLC Paae 17 Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 345.95' @ 11.97 hrs Surf.Area= 5,248 sf Storage= 19,892 cf Plug -Flow detention time= 25.6 min calculated for 3.547 of (100% of inflow) Center -of -Mass det. time= 25.8 min (791.4 - 765.6) Volume Invert Avail.Storage Storage Description #1 340.00' 20,135 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 340.00 1,634 0 0 342.00 2,690 4,324 4,324 344.00 3,921 6,611 10,935 346.00 5,279 9,200 20,135 Device Routing Invert Outlet Devices #1 Primary 339.80' 30.0" Round Culvert L= 65.4' Ke= 0.600 Inlet / Outlet Invert= 339.80' / 339.21' S= 0.0090 '/' Cc= 0.900 n= 0.012 #2 Device 1 340.00' 8.0" Vert. Orifice/Grate C= 0.600 #3 Primary 344.66' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=62.59 cfs @ 11.97 hrs HW=345.93' (Free Discharge) �1=Culvert (Passes 3.98 cfs of 48.94 cfs potential flow) t2=Orifice/Grate (Orifice Controls 3.98 cfs @ 11.39 fps) 3=Orif ice/G rate (Weir Controls 58.62 cfs @ 3.68 fps) Summary for Link 6L: POA 1 Inflow Area = 5.631 ac, 68.89% Impervious, Inflow Depth = 7.57" for 100 yr, 24 hr event Inflow = 64.38 cfs @ 11.97 hrs, Volume= 3.551 of Primary = 64.38 cfs @ 11.97 hrs, Volume= 3.551 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs 1S 2S To POA 2 (IN OD) To P A 2 (Outside LOD) 3L PDA 2 To POA 4 (IN OD) S POA 4 S4 Reach Aon Llnk 4S 5S To POA 3 (1 OD) To POA 3 (Outside LOD) 4L POA 3 9S To POA 5 (IN L D) 12L POA 5 PostDev Prepared by {enter your company name here} PostDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To POA 2 (IN LOD) Runoff Area=0.236 ac 0.00% Impervious Runoff Depth>0.32" Tc=5.0 min CN=61 Runoff=0.12 cfs 0.006 of Subcatchment2S: To POA 2 (Outside LOD) Runoff Area=1.180 ac 0.00% Impervious Runoff Depth>0.24" Tc=5.0 min CN=58 Runoff=0.37 cfs 0.023 of Subcatchment4S: To POA 3 (IN LOD) Runoff Area=0.123 ac 91.87% Impervious Runoff Depth>2.32" Tc=5.0 min CN=95 Runoff=0.50 cfs 0.024 of Subcatchment5S: To PDA 3 (Outside LOD) Runoff Area=1.506 ac 94.49% Impervious Runoff Depth>2.51" Tc=5.0 min CN=97 Runoff=6.41 cfs 0.315 of Subcatchment7S: To POA 4 (IN LOD) Runoff Area=0.105 ac 10.48% Impervious Runoff Depth>0.45" Tc=5.0 min CN=65 Runoff=0.09 cfs 0.004 of Subcatchment9S: To POA 5 (IN LOD) Runoff Area=0.315 ac 71.43% Impervious Runoff Depth>2.14" Tc=5.0 min CN=93 Runoff=1.22 cfs 0.056 of Link 3L: POA 2 Inflow=0.49 cfs 0.030 of Primary=0.49 cfs 0.030 of Link 4L: POA 3 Inflow=6.92 cfs 0.338 of Primary=6.92 cfs 0.338 of Link 11 L: POA 4 Inflow=0.09 cfs 0.004 of Primary=0.09 cfs 0.004 of Link 12L: POA 5 Inflow=1.22 cfs 0.056 of Primary=1.22 cfs 0.056 of Total Runoff Area = 3.465 ac Runoff Volume = 0.428 of Average Runoff Depth = 1.48" 48.86% Pervious = 1.693 ac 51.14% Impervious = 1.772 ac PostDev Prepared by {enter your company name here} PostDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Summary for Subcatchment 1S: To POA 2 (IN LOD) Runoff = 0.12 cfs @ 11.99 hrs, Volume= 0.006 af, Depth> 0.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Descriotion 0.000 58 Woods/grass comb., Good, HSG B 0.236 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 0.236 61 Weighted Average 0.236 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (f /ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: To POA 2 (Outside LOD) Runoff = 0.37 cfs @ 12.00 hrs, Volume= 0.023 af, Depth> 0.24" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Descriotion 1.180 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 1.180 58 Weighted Average 1.180 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: To POA 3 (IN LOD) Runoff = 0.50 cfs @ 11.95 hrs, Volume= 0.024 af, Depth> 2.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" PostDev Prepared by {enter your company name here} Area (ac) CN Description PostDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.008 61 >75% Grass cover, Good, HSG B 0.060 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.002 80 >75% Grass cover, Good, HSG D 0.053 98 Impervious. HSG D 0.123 95 Weighted Average 0.010 8.13% Pervious Area 0.113 91.87% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: To POA 3 (Outside LOD) Runoff = 6.41 cfs @ 11.95 hrs, Volume= 0.315 af, Depth> 2.51" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.747 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.083 80 >75% Grass cover, Good, HSG D 0.676 98 Impervious. HSG D 1.506 97 Weighted Average 0.083 5.51 % Pervious Area 1.423 94.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To POA 4 (IN LOD) Runoff = 0.09 cfs @ 11.98 hrs, Volume= 0.004 af, Depth> 0.45" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" PostDev Prepared by {enter your company name here} Area (ac) CN Description PostDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.094 61 >75% Grass cover, Good, HSG B 0.011 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.000 98 Impervious. HSG D 0.105 65 Weighted Average 0.094 89.52% Pervious Area 0.011 10.48% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 5 (IN LOD) Runoff = 1.22 cfs @ 11.95 hrs, Volume= 0.056 af, Depth> 2.14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.090 80 >75% Grass cover, Good, HSG D 0.225 98 Impervious. HSG D 0.315 93 Weighted Average 0.090 28.57% Pervious Area 0.225 71.43% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 3L: PDA 2 Inflow Area = 1.416 ac, 0.00% Impervious, Inflow Depth > 0.25" for 1 yr, 24 hr event Inflow = 0.49 cfs @ 12.00 hrs, Volume= 0.030 of Primary = 0.49 cfs @ 12.00 hrs, Volume= 0.030 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PostDev Prepared by {enter your company name here} PostDev Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 7/15/2020 Summary for Link 4L: POA 3 Inflow Area = 1.629 ac, 94.29% Impervious, Inflow Depth > 2.49" for 1 yr, 24 hr event Inflow = 6.92 cfs @ 11.95 hrs, Volume= 0.338 of Primary = 6.92 cfs @ 11.95 hrs, Volume= 0.338 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 11L: POA 4 Inflow Area = 0.105 ac, 10.48% Impervious, Inflow Depth > 0.45" for 1 yr, 24 hr event Inflow = 0.09 cfs @ 11.98 hrs, Volume= 0.004 of Primary = 0.09 cfs @ 11.98 hrs, Volume= 0.004 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 12L: POA 5 Inflow Area = 0.315 ac, 71.43% Impervious, Inflow Depth > 2.14" for 1 yr, 24 hr event Inflow = 1.22 cfs @ 11.95 hrs, Volume= 0.056 of Primary = 1.22 cfs @ 11.95 hrs, Volume= 0.056 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PostDev Prepared by {enter your company name here} PostDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: To POA 2 (IN LOD) Runoff Area=0.236 ac 0.00% Impervious Runoff Depth>1.53" Tc=5.0 min CN=61 Runoff=0.71 cfs 0.030 of Subcatchment2S: To POA 2 (Outside LOD) Runoff Area=1.180 ac 0.00% Impervious Runoff Depth>1.32" Tc=5.0 min CN=58 Runoff=3.03 cfs 0.130 of Subcatchment4S: To POA 3 (IN LOD) Runoff Area=0.123 ac 91.87% Impervious Runoff Depth>4.61" Tc=5.0 min CN=95 Runoff=0.96 cfs 0.047 of Subcatchment5S: To PDA 3 (Outside LOD) Runoff Area=1.506 ac 94.49% Impervious Runoff Depth>4.78" Tc=5.0 min CN=97 Runoff=11.95 cfs 0.600 of Subcatchment7S: To POA 4 (IN LOD) Runoff Area=0.105 ac 10.48% Impervious Runoff Depth>1.84" Tc=5.0 min CN=65 Runoff=0.38 cfs 0.016 of Subcatchment9S: To POA 5 (IN LOD) Runoff Area=0.315 ac 71.43% Impervious Runoff Depth>4.43" Tc=5.0 min CN=93 Runoff=2.41 cfs 0.116 of Link 3L: POA 2 Inflow=3.74 cfs 0.160 of Primary=3.74 cfs 0.160 of Link 4L: POA 3 Inflow=12.91 cfs 0.648 of Primary=12.91 cfs 0.648 of Link 11 L: POA 4 Inflow=0.38 cfs 0.016 of Primary=0.38 cfs 0.016 of Link 12L: POA 5 Inflow=2.41 cfs 0.116 of Primary=2.41 cfs 0.116 of Total Runoff Area = 3.465 ac Runoff Volume = 0.940 of Average Runoff Depth = 3.26" 48.86% Pervious = 1.693 ac 51.14% Impervious = 1.772 ac PostDev Prepared by {enter your company name here} PostDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 Summary for Subcatchment 1S: To POA 2 (IN LOD) Runoff = 0.71 cfs @ 11.97 hrs, Volume= 0.030 af, Depth> 1.53" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Descriotion 0.000 58 Woods/grass comb., Good, HSG B 0.236 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 0.236 61 Weighted Average 0.236 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (f /ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: To POA 2 (Outside LOD) Runoff = 3.03 cfs @ 11.97 hrs, Volume= 0.130 af, Depth> 1.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Descriotion 1.180 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B * 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D * 0.000 98 Impervious, HSG D 1.180 58 Weighted Average 1.180 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: To POA 3 (IN LOD) Runoff = 0.96 cfs @ 11.95 hrs, Volume= 0.047 af, Depth> 4.61" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" PostDev Prepared by {enter your company name here} Area (ac) CN Description PostDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.008 61 >75% Grass cover, Good, HSG B 0.060 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.002 80 >75% Grass cover, Good, HSG D 0.053 98 Impervious. HSG D 0.123 95 Weighted Average 0.010 8.13% Pervious Area 0.113 91.87% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: To POA 3 (Outside LOD) Runoff = 11.95 cfs @ 11.95 hrs, Volume= 0.600 af, Depth> 4.78" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.747 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.083 80 >75% Grass cover, Good, HSG D 0.676 98 Impervious. HSG D 1.506 97 Weighted Average 0.083 5.51 % Pervious Area 1.423 94.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 7S: To POA 4 (IN LOD) Runoff = 0.38 cfs @ 11.96 hrs, Volume= 0.016 af, Depth> 1.84" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" PostDev Prepared by {enter your company name here} Area (ac) CN Description PostDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 0.000 58 Woods/grass comb., Good, HSG B 0.094 61 >75% Grass cover, Good, HSG B 0.011 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.000 80 >75% Grass cover, Good, HSG D 0.000 98 Impervious. HSG D 0.105 65 Weighted Average 0.094 89.52% Pervious Area 0.011 10.48% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fUft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: To POA 5 (IN LOD) Runoff = 2.41 cfs @ 11.95 hrs, Volume= 0.116 af, Depth> 4.43" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.000 58 Woods/grass comb., Good, HSG B 0.000 61 >75% Grass cover, Good, HSG B 0.000 98 Impervious, HSG B 0.000 79 Woods/grass comb., Good, HSG D 0.090 80 >75% Grass cover, Good, HSG D 0.225 98 Impervious. HSG D 0.315 93 Weighted Average 0.090 28.57% Pervious Area 0.225 71.43% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 3L: PDA 2 Inflow Area = 1.416 ac, 0.00% Impervious, Inflow Depth > 1.36" for 10 yr, 24 hr event Inflow = 3.74 cfs @ 11.97 hrs, Volume= 0.160 of Primary = 3.74 cfs @ 11.97 hrs, Volume= 0.160 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PostDev Prepared by {enter your company name here} PostDev Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 7/15/2020 Summary for Link 4L: POA 3 Inflow Area = 1.629 ac, 94.29% Impervious, Inflow Depth > 4.77" for 10 yr, 24 hr event Inflow = 12.91 cfs @ 11.95 hrs, Volume= 0.648 of Primary = 12.91 cfs @ 11.95 hrs, Volume= 0.648 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 11L: POA 4 Inflow Area = 0.105 ac, 10.48% Impervious, Inflow Depth > 1.84" for 10 yr, 24 hr event Inflow = 0.38 cfs @ 11.96 hrs, Volume= 0.016 of Primary = 0.38 cfs @ 11.96 hrs, Volume= 0.016 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Summary for Link 12L: POA 5 Inflow Area = 0.315 ac, 71.43% Impervious, Inflow Depth > 4.43" for 10 yr, 24 hr event Inflow = 2.41 cfs @ 11.95 hrs, Volume= 0.116 of Primary = 2.41 cfs @ 11.95 hrs, Volume= 0.116 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PANTOPS CORNTER PRE-DEV DRAINAGE MAP RTE 250 INLETS .1, - ----- J/ U -------- I PREOEV TO "-10P / ,' ------ J t i i PREDEV TO DI I ----- I _ --- 9.45AC TOTAL------------ i Fg--z STR 1 , --- `----- - \ PREDEV DRAINAGE INFO TO PREDEV D1: TURF HSG B: 0.67 AC IMPERVIOUS: 0.78 AC TOTAL: 1.45 AC TO PREDEV 8-20P: TURF HSG B: 0.25 AC IMPERVIOUS: 0.25 AC TOTAL: 0.50 AC HYDROLOGIC DATA TO PREDEV D1: Assumed ToC = 5.0 min Q2-vR= 4.68 cfs Q10-YR= 6.16 CfS 80 0 80 160 240 TOTAL TO PREDEV 8-20P: Q2-YR= 8.48 cfs Scale: 1`80' Q10-YR= 11.21 cfs I� it II I;IF— —I I IIII �I I. r �I =J-7 1 j JIyS POSTDEV TO 8- I 0.43 ACRE$ iun I �\ l 1 1 li :B 0 80 1600 :i 0 - --POSTDEV TO D2 & D1 _ 1.42 ACRES - 0.90 AC IMP._ J I r 1 U n I n I� i �1l A i PANTOPS CORNTER POST—DEV DRAINAGE MAP RTE 250 INLETS "- _ , \�) f A I POSTDEV DRAINAGE INFO TO POSTEV D2 & D1: TURF HSG B: 0.52 AC IMPERVIOUS: 0.90 AC TOTAL: 1.42 AC TO POSTEV 8-20P: TURF HSG B: 0.11 AC IMPERVIOUS: 0.32 AC TOTAL: 0.43 AC HYDROLOGIC DATA TO POSTEV D2 & D1: Assumed ToC = 5.0 min 02-YR= 5.01 cfs 010-YR= 6.60 cfs TOTAL TO POSTEV 8-20P: 02-YR= 8.92 cfs 0 10-YR= 11.80 cfs 57 p, �JPaa STR S-17 °RF , O i STR 7.1 STR 7-3P TR7-18P STR 7-2P STATE ROUTE 258 /1 / 100 200 300 A m A m m z 0 R PANTOPS CORNTER EXISTING DOWNSTREAM DRAINAGE MAP RTE 250 INLETS I ❑ J I III ;� PIIII/IIIII/ I II I � /I I I I i 0 I I o —I. ! —I' O m j A m A MAP) 9 r 58 Rte 250 LD-229 Pantops Corner From To Design Catch. Runoff Increment Accum. Total Total Total Up Down Pipe Invert Pipe Pipe Velocity Flow time Structure Structure Storm Area Coef AC AC TOG Intensity Flow Invert Invert Length Slope Diameter Capacity Increment (ac) (min) (in/hr) lots) Elev. Elev. (it) % (in) (cfs) (ft/s) (min) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Predev D1 B-22P 2-yr 1A5 0.62 0.90 0.90 5.00 5.17 4.68 389.50 37Z60 263.0 4.52 % 15 13.70 10.6 0.41 10-yr 5.00 6.81 6.16 11A 0.38 Postdev Di 8-22P 2-yr 1.42 0.68 0.97 0.97 5.00 5.17 5.01 389.50 377.60 263.0 4.52% 15 13.70 10.8 0.41 10-yr 5.00 6.81 6.60 11.6 0.38 8-21P 8-20P 2-yr 0.57 0.83 0.47 0.47 5.00 5.17 2.44 377.80 377.60 8.0 2.50% 15 10.20 6.8 0.02 (Flow to inlet did not change) 10-yr 5.00 6.81 3.21 7.0 0.02 Predev 8-20P 8-4P 2-yr 0.50 0.59 0.30 1.67 5.41 5.07 8.48 377.60 368.00 224.0 429 % 18 21.76 11.9 021 10-yr 5.38 6.70 11.21 12.-- Postdev B-20P 8-413 2-yr 0.43 0.74 0.32 1.76 5.41 5.07 8.92 377.60 368.00 224.0 4.29 % 18 21.80 11 A 0.33 10- r 5.38 6.70 1 11.80 1 12.9 0.29 n Flow at 8-20P 2-yr 2-yr 0.44 10-yr 10-yr 0.59 Postdev Downstream Flows: 8-4P 7-22P 10-yr 0.67 0.82 0.55 2.31 5.67 6.62 15.33 367.10 361.00 291.0 2.10% 18 15.22 8.6 0.56 7-22P 7-18P 10-yr 1.14 0.84 0.96 3.28 6.23 6.47 2121 357.37 348.87 200.0 4.25% 18 21.66 12.3 0.27 7-18P 7-3P 10-yr 1.00 0.85 0.85 4.13 6.50 6.40 26.44 348.39 342.50 147.0 4.01 % 18 18.16 10.3 0.24 7-313 7-1 P 10-yr 2.15 0.90 1.90 6.03 6.74 6.34 3823 339.78 338.04 55.0 3.16 % 24 40.21 14.6 0.06 7-1 P 6-16P 10-yr 0.32 0.85 0.28 6.30 6.80 6.33 39.88 335.40 330.40 9&0 5.26 % 24 51.88 18.3 0.09 6-16P 6-17P 10-yr 0.53 0.85 0.46 6.77 6.89 6.31 42.68 330.30 312.10 79.0 23.04% 24 108.59 32.7 0.04 59 Rte 250 bdets LD-347 Hydraulic Grade Line n = 0.013 Inlet Number 1 Outlet Water Surface Elev 2 Do 3 Qc 4 L. 5 Sb % 6 Hr 7 Junction Loss Final H 19 Inlet Water Surface Elev. 20 Rim. Elev 21 Vo (8) Ho (9) Q; (10) V; (11) Qvi (12) H; (13) Angle (14) Hn (15) Hr (16) 1.3`Hr (17) 0.5H, (18) 6-16P 313.70 2.00 42.68 79.00 3.560 % 2.812 32.69 4.9781 39.88 18.30 729.9 1.820 15 0.988 7.786 10.596 324.30 338.65 7-1P 332.00 2.00 39.88 95.00 3.109% 2.954 18.30 2.2361 38.23 14.59 557.8 1.157 40 1.421 4.814 7.768 339.77 343.58 7-3P 339.77 2.00 38.23 55.00 2.857% 1-571 14.59 0.1983 26.44 10.28 271.8 0.574 5 0.098 0.871 2.442 342.21 345.50 7-18P 343.70 1.50 26.44 147.00 6.337% 9.315 10.28 0.0985 21.21 12.25 259.8 0.816 5 0.140 1.054 0.5269 9.842 353.54 354.57 7-22P 353.54 1.50 21.21 200.00 4.0799% 8.158 12.25 0.1165 15.33 8.60 131.8 0.402 3 0.057 0.576 0.2879 8.446 361.99 364.37 8-4P 362.20 1.50 15.33 291.00 2.130% 6.199 8.60 0.0459 11.80 12.90 152.2 0.904 1 0.103 1.054 0.5269 6.726 368.93 371.70 Postdev 8-20P 36920 1.50 11.80 224.00 1.262% 2.828 11.40 0.0607 11.21 12.00 134.6 0.783 1 0.089 0.953 3.781 372.98 381.60 Postdev D1 378.60 1.25 6.60 263.00 1.044% 2.745 11.60 1.2537 6.60 7.75 51.1 0.326 69 0.560 2.140 1.0698 3.814 382.41 393.60 Postdev, D2 390.70 1.25 6.60 8.50 1.044% 0.089 7.75 0.0373 6.60 7.75 51.1 0.009 - 0.037 0.084 0.1091 0.0546 0.143 390.84 393.09 'Outlet W SE is listed as the greater of either the calculated tailwater or the invert out. 60 Stormwater Quality Calculations VRRM Redevelopment Spreadsheet Nutrient Credit Letter of Availability Prounafterne Richmond )30p RIellmantl Roatl dere Y Linen Oevelaparrin ojMi V. Ske Information Post -Development pm(ecbl (Treatment Volume and Loads( Enter Total Disturbed Mae (dome) abz cne[x: -6Mp Magri SpxlfiM;ona ut[ zoli Oran sWs S. spea Q unea.e/aRm No �— enearerarea:emered �,.emN J � mmmmameedrea mreree) ✓ h-ReOeuelopn anands uvtta (aaeel ASair usual Ciro", Oulart, arv� 3wm I�1- meemmea vren/ece�wa�e re s�nvonl-mrurialia mmr ts6 all w=•mrsmlaw wll ... . .. ib and mouraffounflummodur ur ruil mpW wg6rvllrvlraresl E, wrww nayeena—,r Wnl worard lmn rewu:[vu<rl.en mceayMce��l a.— 0.fa E% It 3� 31) ovwesnaopvm �^/Poen ya.e al _ enar—n weieare as •roves 6% ua:.a. r Ia�l � Ivalemla'YM o at %wrFeiiue are 390 N>wr�++P�vxea rewvmn .. rela�l "a l^fie zm/oce..iPs. rre«.p.nme weaaao`" evl and p03 %fovea a9% 6% vmxgeJ)uvrmer�nl wan"aio M N rnmraeenrt E]% ImlemwrdealH+1 1. )4e urairat ua. k�l art Wert —1 u'R*ce��m pas v°`ryure "an �1 Hmwwo=I an Ma�w"a•I pes ass a®I+RI am Treatment Volume and Nutrient Load Treatment Volume and Nutrient Load I �� Imm aIIti ail)) memw rearlaraNe p3% R31aere.ullum a aiEr3 ea It unenrece r mwnruwn d.6d[. Panem—m Im 31.. lavey Pan �LanI—']mm 9639 Tn. �ii—ouax r arxoneopemrndmw:rvutreneFair I�IvI laamrap r —1 T ii.nationer, Te Watl 6.p6 s96 b OnvP T.66 o.duI 6.p5 luvllP.. l.m rim/va•l ll!/vrliP ov�u..eem rpelWYpe � r$ -es.a.i.:i - — m•ml. newtt+Ppeninu+vrwe OWeMI ua azv Nrl� n IW l mv,m/m m.eayunir-aa.NP..mvn r.. g.n.om+w.:�lew+sal� 11 aN ._ ...e. maMu no., 129 MM•I%rNeu� LW +aelmm mmrsre riirmvw MemrvlM=44^+m=amvrene.: e .lou ne� einartallWM .—a.urerawne.».ro•.aam..r. war.emme.,e.�,�ewx�-ka��,,,�,rwemelm.ea mad;, TP Load Andunlon Required Ile/rl z.ss Muddled wards (Informational f tames only) m rod mrm.. .vmlow OWnl at ss Vmrwdura,dopeour Nens.ve I stn IWM Site Results (Water Quality Compliance) Area Checks M.A.A M.A.B o.A.c D.A.D D.A.E AREACHEN FOREST/OVEN SPACE(a[) 0.00 O.W OCO 0.00 O.N OK IMPERVIOUS COVER(a[) IMPERVFDUSCOVFRTRFATED(.c) 0.00 0.00 0.0] O.CO O.W O.CL 0.00 0.00 O.Do O.N OK OK MRE MANAGED MU AA (a<) 0.00 O.W 0.00 0.00 O.D] OK MANAGED TURF AREA TREATED (a<) 0.00 0.00 OK. AREA CHECK ON. OK. OK. OK. OK. Site Treatment Volume (fta) uj, Runoff Reduction Volume and TP By Drainage Area OA.A O.A.B O.A.0 D.A.D OAE TOTAL RUNOFF REDUCTION VOLUME ACHIEVED(tr) 0 0 0 0 0 0 TP LOAO AVAIWBLE FOR REMOVAL(Ib/yr) 0.Do 0.00 0.00 D. O.W 0.00 TP LOAO RFOUCFION ACHIEVED (Ih/yr) 0.00 0.00 0.00 0.00 O.W 0.00 TP LOAD REMAINING (Ib/yr) 0.00 0.00 6C0 0.00 0.0 0.0 NITROGEN LOAM MOLICEON ACHIEVED Pb/YrI 0.00 0.00 OLO 0.00 0.00 000 Total Phosphorus HNAL POST -DEVELOPMENT TP LOAD(lb/yr)P7.t TP LOAD REDUCTION REQUIRED (lb/yrl TPLOADREDUCTIONACHIEVED(lb/yrl W LOAD REMAINING(lb/,): REMAINING TP LOAM REDUCEON REQUIRED (lb/,): 2.59 Total Nitrogen (For Information Purposes) POST-DEVELOPMEM LOAD (Ib/yr) SO.J9 NITROGEN LOAD REDUCTION ACHIEVED (Ib/yr) 0.00 REMAINING POST -DEVELOPMENT NRRWEN LOAD(lb/yrl SO.J9 Mrginia Runoff Reduction Method Mftheet DEQ Virginia Runoff Reduction Method Re -Development Compliance Spreadsheet - Version 3.0 BMP Design Specrcotions List 2013 Draft Stds & Specs Site Summary Project Title: 1300 Richmond Road Date: 44027 Total Rainfall (in): 43 Total Disturbed Acreage: G62 Site Land Cover Summary Pre-ReDevelopment Land Cover (acres) Asolls BSOiIS CSoils DSoils Totals %of Total Forest/Open(acres) 0.00 0.89 0.,0 0.00 0.89 19 Managed Turf(acres) 0.00 0.77 0.00 0,49 1.26 27 Impervious Cover (acres) 1 0.00 0.85 0.00 1.63 2.48 54 4.63 100 Post-ReDevelopment Land Cover (acres) A soils BSoils CSolls DSoils Totals %of Total Forest/Open (acres) 0.00 0.00 0.00 0.00 0.00 0 Managed Turf (acres) 1 0.00 1.02 0.00 0.39 1.41 30 Impervious Cover (acres) 1 0.00 1.48 0.00 1.73 3.22 70 4.63 100 Site Tv and Land Cover Nutrient Loads Final Post -Development post- post Adjusted Pre- (Post-ReDevelopment ReDevelopment Development ReDevelopment &New Impervious) p (New Impervious) Site Rv 0.73 0.68 0.95 0.67 Treatment Volume(fta) 12,190 9,638 2,552 9,482 TP Load(lb/yr) 7.66 6.06 1.60 5.96 total TP Load Reduction Required (lb/yr) 2.59 1.29 1.30 Final Post -Development Load (Post-ReDevelopment & New Impervious) Pre- ReDevelopment TN Load (lb/yr) 54.79 1 43.35 Pre- ReDevelopment Final Post -Development TP Load per acre TP Load per acre :SI (lb/acre/yr) (lb/acre/yr) 1.53 1.66 Summary Pma Virginia Runoff Reduction Method Mftheet Site Compliance Summary Maximum% Reduction Required Belo 20% Pre-ReDevelopment Lwd Total Runoff Volume Reduction (ff) 0 Total TP Load Reduction Achieved (lb/yr) 0.00 Total TN Load Reduction Achieved (lb/yr) 0.00 Remaining Post Development TP Load 7.66 (lb/yr) Remaining TP Load Reduction (lb/yr) 2.59 Required Summary Print Rivanna River Nutrient Bank 16, 2020 KENDRA PATRICK, EIT Project Engineer Shimp Engineering, P.C. 912 East High St. Charlottesville, VA 22902 Kend ra(a)_Sh imp-Engi neeri nq. com With a copy to: Buddy Thomas ( bthomas(aflowauto.com Owner: Flow 1300 Richmond LLC Contact: Buddy Thomas ( bthomasna.flowauto.com) Project: 1300 Richmond Road Project No.: 19.078 DEQ SWM No.: Location: 1300 Richmond Road Charlottesville, VA 22911 Coordinates: (38.03497,-78.45035) Legal Reference: TMP 78-6 & 78-7 Receiving Water: Meadow Creek HUC12: 020802040401 Estimated Credits Required: 2.59 lb Dear Kendra and Mr. Thomas, Certificate No. James-039 This letter is to confirm the availability to your project (referenced above ) of authorized Nutrient Credits sufficient to meet the your estimated requirements of 2.59 Nutrient Credits at our Rivanna River nutrient offset credit bank facility (the "Bank"). The Bank has been registered with the Virginia Department of Environmental Quality (DEQ). These Nutrient Credits are generated and managed under the terms of the Reduction Implementation Plan for the Bank dated November 2017, which was authorized by (DEQ) on September 5, 2018. The Bank has been authorized to provide Nutrient Credits for use in the James River watershed. These credits are transferable to those entities regulated under DEQ's Storm Water Management program in accordance with VA Code 62.1-44.15:27. If we can provide further assistance please feel free to contact our office. Hotel Street Capi C, Bank Sponsor By Its M r Thomas oss I 540-68 -0171 Rivanna River Nutrient Offset Trading Bank, 31 Garrett Street, Warrenton, Virginia 20186 Independent Reports Excerpt from NRCS Soils Report NOAA Precipitation Report 79B Ri�hm0 d F PFW 4 � • v MAPLEGEND Area of Interest (AOI) I ] Area of Interest (AO0 Solis 0 Soil Map Unit Polygons .y Soil Map Unit Lines Soil Map Unit Points Special Point Features V Blowout ® Borrow Pit X Clay Spot O Closed Depression Gravel Pit Gravelly Spot O Landfill A Lava Flow 4& Marsh or swamp �. Mine or Quarry O Miscellaneous Water O Perennial Water V Rock Outcrop + Saline Spot Sandy Spot A Severely Eroded Spot ® Sinkhole Slide or Slip Sodic Spot Custom Soil Resource Report g Spoil Area Q Stony Spot Very Stony Spot Wet spot p Other Special Line Features Water Features Streams and Canals Transportation fi 1 Rails A/ Interstate Highways US Routes Major Roads Local Roads Background . Aerial Photography MAP INFORMATION The soil surveys that comprise your ACI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Albemarle County, Virginia Survey Area Data: Version 13, Sep 17, 2019 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: May 20, 2019—Aug 1, 2019 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. VA Custom Soil Resource Report Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 12D Catoctin silt loam, 15 to 25 percent slopes 2.5 18.4% 23B Yadkin day loam, 2 to 7 percent slopes 3.2 24.0% 71 D Rabun clay loam, 15 to 25 percent slopes 2.6 19.4% 79B Meadowville silt loam, 2 to 7 percent slopes 0.7 5.4% 88 Udorthents, loamy, 2 to 25 percent slopes 4.4 32.8% Totals for Area of Interest 13.3 100.0"A Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic Gass rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. Ll Custom Soil Resource Report Albemarle County, Virginia 12D—Catoctin silt loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2yfhj Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Catoctin and similar soils: 80 percent Estimates are based on observations, Description of Catoctin descriptions, and transects of the mapunit. Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material., Residuum weathered from greenstone Typical profile A - 0 to 5 inches: silt loam Bw - 5 to 18 inches: very channery silt loam C - 18 to 28 inches: extremely channery silt loam R - 28 to 79 inches: bedrock Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat) to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Low (about 3.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Hydric soil rating: No Very low to high (0.00 Custom Soil Resource Report 2313—Yadkin clay loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: 2v7hx Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Yadkin and similar soils: 80 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Yadkin Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material., Residuum weathered from greenstone Typical profile Ap - 0 to 4 inches: clay loam BA - 4 to 10 inches: clay loam Bt - 10 to 63 inches: clay C - 63 to 88 inches: clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Moderate (about 8.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 11 Custom Soil Resource Report 71 D—Rabun clay loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2xxyk Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun and similar soils: 75 percent Estimates are based on observations, Description of Rabun descriptions, and transects of the mapunit. Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat) high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to Available water storage in profile: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Hydric soil rating: No IV Custom Soil Resource Report 79B—Meadowville silt loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: 2v7k1 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Meadowville, occasionally flooded, and similar soils: 80 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Meadowville, Occasionally Flooded Setting Landform: Drainageways Landform position (two-dimensional): Footslope Landform position (three-dimensional): Head slope Down -slope shape: Concave Across -slope shape: Convex Parent material., Colluvium derived from igneous rock Typical profile A - 0 to 18 inches: silt loam Bt - 18 to 53 inches: silty clay loam 2C - 53 to 79 inches: gravelly clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: Occasional Frequency of ponding: None Available water storage in profile: High (about 9.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: B Hydric soil rating: No 13 Custom Soil Resource Report 88—Udorthents, loamy, 2 to 25 percent slopes Map Unit Setting National map unit symbol: 2xxz3 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Udorthents and similar soils: 85 percent Minor components: 5 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Udorthents Setting Landform: Interfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material. Residuum weathered from granite and gneiss Properties and qualities Slope: 2 to 25 percent Depth to restrictive feature: More than 80 inches Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Minor Components Hatboro, occasionally flooded Percent of map unit: 5 percent Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Hydric soil rating: Yes 14 2/222020 Precipitation Frequency Data Server NOAA Atlas 14, Volume 2, Version 3 r°�-� Location name: Charlottesville Virginia USA' s°`� . Latitude: 38evatio, Longitude:-78.4504° e W Elevation: 410.47 ft" 7 a 1 'source: ESRI Maps ''+�y,r �.f -source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland PF tabular I PF graphical I Maps & aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Average recurrence Interval (years) Duration 1 2 5 10 25 50 1 100 00 200 500 1000 5 n13)0.557--0 6 (0.3118-0 392) (0.3079-0-0466) (0.443-0.545) (0.497--0 13) 687) (0.603-0.746) (0.645-0 802)11(0.68 0 854) (07 24-0 919) (07 58-0 974) 0.564 &672 0.788 0.886 0.993 1.08 1.16 1.23 1.32 1.38 10-min (0.508-0.626) (0.606-0.745) (0709-0.873) (0.795-0.980) (0.888-1.10) (0.961-1.19) (1.02-1.27) 08- (1.1.35) (1.15-1.45) (1.19-1.53 ) 0.706 0.844 0.996 1.12 1.26 1.37 1.46 1.65 1.66 1.74 15-min (0.635-0.783) (0.762-0.937) (0.897-1.10) 1 (1.01-1.24) 1 (1.131.39) 1 (1.22-1.51) 1 (1.29-1.61) 1 (1.36-1.71) 1,44-1.83 1.501.93) 0.966 1.17 1.42 1.62 1.86 2.06 224 2A1 264 281 30.min (0.870-1.07) (1.05.129) 1 (1.27-1.57) 1 (1.46-1.80) 1 (1.67-2.06) (1.83-2.27) (1.98-2.47) (2.12-2.66) (2.30-2.91) (2.43-3.12) 121 1.46 1.82 2.11 248 2.79 3.08 3.39 3.78 4.11 60-min 1.09-1.34) 1.32-1.62) 1.63-2.01) 1.90-2.34) (2.22-2.74) (2.48-3.0 (2.73-3.40) (2.98-173) (329-4.18) (3.54-4.55) 3.07 5.47 2-hr (1.27-11.66) (1.54-2.9) (1. 3 2950) (2.27 2893) (268-3.48) (3A3 3894) (3.37-4A2) 3.73-4.91) (4. 0--5.60) (4: 06.20) 1.59 1.92 240 2.81 3.36 3.81 4.28 4.76 5.43 6.00 3-hr (1.39-1.82) 1.68-220 (2.10-2.76) (2.45-3.22) (2.913.83) (329-4.34) (3.67-4.87) (4.05-5AZI) (4.57-6.20) (4.996.86) 3.02 6.57 6-hr (17 9-2.2$ (2.15-23715) 2603.43 (3. 2-4603) (3.73U28 3-4.84) (4:3553) (4.776.28) (5.32-27A8) 6. 9-8.22) 67 4-9.23) 7.30 8.33 11.2 12-hr (224-2.90) (269.3.50) (3.344 35) (3.85-5'15) (47 66.24) (5A7-77.22) (62 0-8.27) (6.99-9.43) (8.9.65 2) (9.09- 2.7) 24-hr (2. 20340) (3294.12) 419-�526) 4.94-6.20) (663-7.69) 6. 5-8.79 (7.94-0.1) (9.00 11.6) (10.5- 3.8) 11.8-15.7) 2-dey (32 0-3.99) (3.89-4.84) (4. 36-15) (57 8-7.22) (6.996.77) (79 8-1160.1) (9.04131.5) (102- 3.1) (11 &15.4) (131517.3) 3.80 4.61 5.86 6.88 &37 9.62 11.0 12.4 14.6 16.4 34ay (3.454.21) (4.185.11) (5.30649) (6.22-7.61) (7.52-9.24) (8.58-10.6) (9.72-12.1) (10.9-13.7) (12.7-16.2) (14.1-18.2 4-dey (37 04.44) (4.4785.37) (5.666.82) (6.656.00) (865-9.71) (9.19A11.2) (10.4- 2.7) 11 7314.4) 1315- 6.9 15.0. 9.1) 7dey (4.315.11 (5196.16) (647-076.70) (7.52-8.5) (960 0A) (102- 2.3) (11.5-13.9) 12.8- 5.7) (14.7- 8.3) 1 (162 0.4) 10-dey 4.91575) (5. M6.90) 7.278852) 8.379.84) (9.91---111. 111-1.2) (12.4-14.8) (13.8- 6.6) (15.019.0) (171921.1) 17.7 1.4 20-dey (653-7.47) (78 0-8.91) (94140.8) (107- 2.2) (123--14.2) (13.6-5.7) (15..0-127.4) (16.3- 9.0) (1819 1.3) (1924- 3.1) 6.56 10.7 720 13.4 15.3 16.7 18.0 79A 21.7 22.5 30-day (8.08-9.11 9.55-10.8 (11.3-12.8) (12.6-14.3) (14.3-16.2) (15.6-17.7) (16.8-192) (18.0-20.6) (19.5-22.6) (20.7-24.1) 10.7 126 14.8 16.4 18.4 19.9 21.4 22.8 24.6 T 26.0 45-tlay (10.1-113) 1 (11.9-13A) 1 (13.9-15.6) 1 (15.4-17.3) (17.3-19.5) (18.7-21.1) (20.022.7) (21.3-24.2) 1 (22.9-26.2) 1 (24.027.7) 60-daY 1119-13.2) (14.0-5.6) (16�1 8.0) 1Z76- 9.8) ('1920Y2.1) (21 3.7) (22.6-25.4) 23?9-27.0) (25 0.0) 267830.5 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a [Numbers en duration and average recunence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not ecked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. ease refer to NOAA Atlas 14 document for more information. Back to Top PF graphical https:Hhdsc.nws.noaa.gov/hdsrlpfdstpfds_printpage.html?lat=38.0343&Ion=-78.4504&data=depth&units=english&series=pds 114