Loading...
HomeMy WebLinkAboutWPO202100063 Stormwater Management Maintenance Agree. 2021-12-06 (2)1S 7S DA-Pre DA-Offsit( Lvl 1 Onsite Ext'd Detention w/R-Reduction Subcat Reach Aon Llnk Dunlora WPO-SWM2 Prepared by HP Inc. Project Notes Defined 10 rainfall events from Albemarle Rainfall OF Printed 12/6/2021 Dunlora WPO-SWM2 Prepared by HP Inc. Rainfall Events Listing (selected events) Event# Event Storm Type Curve Mode Duration B/B Depth AMC Name (hours) (inches) 1 1-yr Type II 24-hr Default 24.00 1 2.97 2 2 2-yr Type II 24-hr Default 24.00 1 3.59 2 3 10-yr Type II 24-hr Default 24.00 1 5.43 2 4 25-yr Type II 24-hr Default 24.00 1 6.67 2 5 100-yr Type II 24-hr Default 24.00 1 8.90 2 Printed 12/6/2021 Dunlora WPO-SWM2 Prepared by HP Inc. Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 4.660 80 (1S) 6.960 61 (4S) 0.960 78 (7S) 12.580 69 TOTAL AREA Printed 12/6/2021 Dunlora WPO-SWM2 Prepared by HP Inc. Area Soil Soil Listing (all nodes) Subcatchment (acres) Group Numbers 0.000 HSG A 0.000 HSG B 0.000 HSG C 0.000 HSG D 12.580 Other 1S, 4S, 7S 12.580 TOTAL AREA Printed 12/6/2021 Dunlora WPO-SWM2 Prepared by HP Inc. Ground Covers (all nodes) Printed 12/6/2021 HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchment (acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers 0.000 0.000 0.000 0.000 12.580 12.580 1 S, 4S, 7S 0.000 0.000 0.000 0.000 12.580 12.580 TOTAL AREA Dunlora WPO-SWM2 Prepared by HP Inc. Pipe Listing (all nodes) Printed 12/6/2021 Line# Node In -Invert Out -Invert Length Slope n Width Diam/Height Inside -Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 6P 374.00 370.00 102.0 0.0392 0.020 0.0 24.0 0.0 Dunlora WPO-SWM2 Type 1124-hr 1-yrRainfall=2.97" Prepared by HP Inc. Printed 12/6/2021 HvdroCADO 10.10-6a s/n 08126 © 2020 HvdroCAD Software Solutions LLC Paae 8 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Subcatchment 1S: DA-Post Runoff Area=4.660 ac 0.00% Impervious Runoff Depth>1.12" Tc=8.0 min CN=80 Runoff=9.36 cfs 0.435 of Subcatchment 4S: DA-Pre Runoff Area=6.960 ac 0.00% Impervious Runoff Depth>0.30" Tc=10.5 min CN=61 Runoff=2.42 cfs 0.174 of Subcatchment 7S: DA-Offsite Runoff Area=0.960 ac 0.00% Impervious Runoff Depth>1.00" Tc=8.0 min CN=78 Runoff=1.73 cfs 0.080 of Pond 6P: Lvl 1 Onsite Ext'd Detention Peak Elev=386.92' Storage=15,318 cf Inflow=11.09 cfs 0.515 of Primary=2.74 cfs 0.495 of Secondary=0.00 cfs 0.000 of Outflow=2.74 cfs 0.495 of Total Runoff Area = 12.580 ac Runoff Volume = 0.689 of Average Runoff Depth = 0.66" 100.00% Pervious = 12.580 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Summary for Subcatchment 1 S: DA-Post Runoff = 9.36 cfs @ 12.00 hrs, Volume= 0.435 af, Depth> 1.12" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.97" Area (ac) CN Description 4.660 80 4.660 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 1S: DA-Post Hydrograph I 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Pre Runoff = 2.42 cfs @ 12.06 hrs, Volume= 0.174 af, Depth> 0.30" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.97" Area (ac) CN Description 1.180 61 1.540 61 6.960 61 Weighted Average 6.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.5 Direct Entry, Subcatchment 4S: DA-Pre Hydrograph ',. ❑Runoff 2 a2 cfs Type II 24-hr 1-yr Rainfall=2.97" 2 Run fre 660 c Ru lu4f R D hno10OTc=10.5 min CN=I61 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (houm) Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Summary for Subcatchment 7S: DA-Offsite Runoff = 1.73 cfs @ 12.00 hrs, Volume= 0.080 af, Depth> 1.00" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1-yr Rainfall=2.97" Area (ac) CN 0.960 78 0.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 7S: DA-Offsite Hydrograph 173 cfs Type II 24-hr 1-yr Rainfall=2.97" Runoff Area=0.960 ac Runoff Volume=0.080 of Runoff Depth>1.00" Tc=8.0 min CN=78 9 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ RunoH Dunlora WPO-SWM2 Prepared by HIP Inc. Type Il 24-hr 1-yr Rainfall=2.97" Printed 12/6/2021 Summary for Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Top of Berm 386.67 Inflow Area = 5.620 ac, 0.00% Impervious, Inflow Depth > 1.10" for 1-yr event Inflow = 11.09 cfs @ 12.00 hrs, Volume= 0.515 of Outflow = 2.74 cfs @ 12.19 hrs, Volume= 0.495 af, Atten= 75%, Lag= 11.6 min Primary = 2.74 cfs @ 12.19 hrs, Volume= 0.495 of Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 385.10' Surf.Area= 3,596 sf Storage= 6,801 cf Peak Elev= 386.92' @ 12.19 hrs Surf.Area= 5,447 sf Storage= 15,318 cf (8,516 cf above start) Plug -Flow detention time= 166.4 min calculated for 0.339 of (66% of inflow) Center -of -Mass det. time= 41.2 min ( 841.1 - 799.9 ) Volume Invert Avail.Storage Storage Description #1 380.00' 52,059 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 380.00 243 0 0 382.00 683 926 926 384.00 2,074 2,757 3,683 386.00 4,841 6,915 10,598 388.00 6,161 11,002 21,600 390.00 7,591 13,752 35,352 392.00 9,116 16,707 52,059 Device Routing Invert Outlet Devices #1 Primary 374.00' 24.0" Round 102 If @ 3.92 L= 102.0' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 374.00' / 370.00' S= 0.0392 '/' Cc= 0.900 n= 0.020, Flow Area= 3.14 sf #2 Device 1 385.10' 8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 386.50' 12.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Device 1 389.30' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Secondary 391.00' 8.0' long x 16.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=2.72 cfs @ 12.19 hrs HW=386.92' (Free Discharge) t1=102 If @ 3.92 (Passes 2.72 cfs of 44.87 cfs potential flow) 2=Orifice/Grate (Orifice Controls 2.05 cfs @ 5.86 fps) 3=Orifice/Grate (Orifice Controls 0.68 cfs @ 2.20 fps) =Orifice/Grate ( Controls 0.00 cfs) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=385.10' (Free Discharge) t5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Duniora WPO-SWM2 Prepared by HP Inc. 1 2 Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Hydrograph nflow Area=5.620 ac Peak Elev=386.92' Storage=15,318 cf- 2 74 c(s 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Time (hours) ■ Inflow ❑ Outflow ❑ Primary ❑ Secondary Dunlora WPO-SWM2 Type 1124-hr 2-yr Rainfall=3.59 " Prepared by HP Inc. Printed 12/6/2021 HvdroCADO 10.10-6a s/n 08126 © 2020 HvdroCAD Software Solutions LLC Paoe 14 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Subcatchment 1S: DA-Post Runoff Area=4.660 ac 0.00% Impervious Runoff Depth>1.57" Tc=8.0 min CN=80 Runoff=13.04 cfs 0.609 of Subcatchment 4S: DA-Pre Runoff Area=6.960 ac 0.00% Impervious Runoff Depth>0.53" Tc=10.5 min CN=61 Runoff=5.23 cfs 0.309 of Subcatchment 7S: DA-Offsite Runoff Area=0.960 ac 0.00% Impervious Runoff Depth>1.43" Tc=8.0 min CN=78 Runoff=2.46 cfs 0.115 of Pond 6P: Lvl 1 Onsite Ext'd Detention Peak Elev=387.48' Storage=18,461 cf Inflow=15.50 cfs 0.723 of Primary=5.02 cfs 0.700 of Secondary=0.00 cfs 0.000 of Outflow=5.02 cfs 0.700 of Total Runoff Area = 12.580 ac Runoff Volume = 1.033 of Average Runoff Depth = 0.99" 100.00% Pervious = 12.580 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 2-yrRainfall=3.59" Printed 12/6/2021 Summary for Subcatchment 1 S: DA-Post Runoff = 13.04 cfs @ 12.00 hrs, Volume= 0.609 af, Depth> 1.57" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 2-yr Rainfall=3.59" Area (ac) CN Description 4.660 80 4.660 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 1S: DA-Post Hydrograph 11- 0 LL ��N��� ���■1ii4�'1iiWifilifi�i'i�'i MOMEMEME■ MEN": 1' 1-RO M,WMM MOMENIMM■ IMMEMEN omiYilYl■ ------. -------- u / ts V lu 11 lL I 14 1t. 1l1 1/ its I Lu Time (hours) ■ Rurwff Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 2-yr Rainfall=3.59 " Printed 12/6/2021 Summary for Subcatchment 4S: DA-Pre Runoff = 5.23 cfs @ 12.05 hrs, Volume= 0.309 af, Depth> 0.53" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 2-yr Rainfall=3.59" Area (ac) CN Description 1.180 61 1.540 61 6.960 61 Weighted Average 6.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.5 Direct Entry, Subcatchment 4S: DA-Pre Hydrograph ❑ RunoH 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (houm) Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 2-yrRainfall=3.59" Printed 12/6/2021 Summary for Subcatchment 7S: DA-Offsite Runoff = 2.46 cfs @ 12.00 hrs, Volume= 0.115 af, Depth> 1.43" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 2-yr Rainfall=3.59" Area (ac) CN Description 0.960 78 0.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 7S: DA-Mite Hydrograph ',,,. ❑ Runoff LRunoff Type II 24-hr yr Rainfall=3.59" 2 ff Area=0.960 ac Volume=0.115 of noff Depth>1.43" Tc=8.0 min CN=78 9 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM2 Prepared by HIP Inc. Type // 24-hr 2-yr Rainfall=3.59" Printed 12/6/2021 Summary for Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Top of Berm 386.67 Inflow Area = 5.620 ac, 0.00% Impervious, Inflow Depth > 1.54" for 2-yr event Inflow = 15.50 cfs @ 12.00 hrs, Volume= 0.723 of Outflow = 5.02 cfs @ 12.15 hrs, Volume= 0.700 af, Atten= 68%, Lag= 9.5 min Primary = 5.02 cfs @ 12.15 hrs, Volume= 0.700 of Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 385.10' Surf.Area= 3,596 sf Storage= 6,801 cf Peak Elev= 387.48' @ 12.15 hrs Surf.Area= 5,815 sf Storage= 18,461 cf (11,660 cf above start) Plug -Flow detention time= 134.7 min calculated for 0.544 of (75% of inflow) Center -of -Mass det. time= 38.8 min ( 831.6 - 792.8 ) Volume Invert Avail.Storage Storage Description #1 380.00' 52,059 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 380.00 243 0 0 382.00 683 926 926 384.00 2,074 2,757 3,683 386.00 4,841 6,915 10,598 388.00 6,161 11,002 21,600 390.00 7,591 13,752 35,352 392.00 9,116 16,707 52,059 Device Routing Invert Outlet Devices #1 Primary 374.00' 24.0" Round 102 If @ 3.92 L= 102.0' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 374.00' / 370.00' S= 0.0392 '/' Cc= 0.900 n= 0.020, Flow Area= 3.14 sf #2 Device 1 385.10' 8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 386.50' 12.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Device 1 389.30' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Secondary 391.00' 8.0' long x 16.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=5.02 cfs @ 12.15 hrs HW=387.47' (Free Discharge) t1=102 If @ 3.92 (Passes 5.02 cfs of 45.70 cfs potential flow) 2=Orifice/Grate (Orifice Controls 2.40 cfs @ 6.88 fps) 3=Orifice/Grate (Orifice Controls 2.62 cfs @ 3.36 fps) =Orifice/Grate ( Controls 0.00 cfs) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=385.10' (Free Discharge) t5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 2-yr Raintall=3.59 " Printed 12/6/2021 Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Hydrograph . ■ Inflow 15 so dr ❑ Outflow 17 Inflow'Area=6.620 ac Else ondary ,6 Peak Elev=387.48' 15 14 Storage=18,461 cf 13 � (11Z 1 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Time (hours) Dunlora WPO-SWM2 Type // 24-hr 10-yr Rainfall=5.43" Prepared by HP Inc. Printed 12/6/2021 HvdroCADO 10.10-6a s/n 08126 © 2020 HvdroCAD Software Solutions LLC Paoe 20 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Subcatchment 1S: DA-Post Runoff Area=4.660 ac 0.00% Impervious Runoff Depth>3.03" Tc=8.0 min CN=80 Runoff=24.64 cfs 1.179 of Subcatchment 4S: DA-Pre Runoff Area=6.960 ac 0.00% Impervious Runoff Depth>1.47" Tc=10.5 min CN=61 Runoff=16.35 cfs 0.850 of Subcatchment 7S: DA-Offsite Runoff Area=0.960 ac 0.00% Impervious Runoff Depth>2.85" Tc=8.0 min CN=78 Runoff=4.81 cfs 0.228 of Pond 6P: Lvl 1 Onsite Ext'd Detention Peak Elev=389.20' Storage=29,494 cf Inflow=29.44 cfs 1.407 of Primary=8.87 cfs 1.375 of Secondary=0.00 cfs 0.000 of Outflow=8.87 cfs 1.375 of Total Runoff Area = 12.580 ac Runoff Volume = 2.257 of Average Runoff Depth = 2.15" 100.00% Pervious = 12.580 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM2 Prepared by HP Inc. Type/1 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Subcatchment 1 S: DA-Post Runoff = 24.64 cfs @ 11.99 hrs, Volume= 1.179 af, Depth> 3.03" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=5.43" Area (ac) CN Description 4.660 80 4.660 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 1S: DA-Post Hydrograph ■ Rurwff 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM2 Prepared by HP Inc. Type/1 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Pre Runoff = 16.35 cfs @ 12.03 hrs, Volume= 0.850 af, Depth> 1.47" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=5.43" Area (ac) CN Description 1.180 61 1.540 61 6.960 61 Weighted Average 6.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.5 Direct Entry, Subcatchment 4S: DA-Pre Hydrograph ■ Rurwff 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Duniora WPO-SWM2 Prepared by HP Inc. Type/1 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Subcatchment 7S: DA-Offsite Runoff = 4.81 cfs @ 11.99 hrs, Volume= 0.228 af, Depth> 2.85" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10-yr Rainfall=5.43" Area (ac) CN 0.960 78 0.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 7S: DA-Offsite Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM2 Prepared by HIP Inc. Type Il 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Top of Berm 386.67 Inflow Area = 5.620 ac, 0.00% Impervious, Inflow Depth > 3.00" for 10-yr event Inflow = 29.44 cfs @ 11.99 hrs, Volume= 1.407 of Outflow = 8.87 cfs @ 12.16 hrs, Volume= 1.375 af, Atten= 70%, Lag= 9.9 min Primary = 8.87 cfs @ 12.16 hrs, Volume= 1.375 of Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 385.10' Surf.Area= 3,596 sf Storage= 6,801 cf Peak Elev= 389.20' @ 12.16 hrs Surf.Area= 7,018 sf Storage= 29,494 cf (22,692 cf above start) Plug -Flow detention time= 97.2 min calculated for 1.219 of (87% of inflow) Center -of -Mass det. time= 37.4 min ( 815.9 - 778.5 ) Volume Invert Avail.Storage Storage Description #1 380.00' 52,059 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 380.00 243 0 0 382.00 683 926 926 384.00 2,074 2,757 3,683 386.00 4,841 6,915 10,598 388.00 6,161 11,002 21,600 390.00 7,591 13,752 35,352 392.00 9,116 16,707 52,059 Device Routing Invert Outlet Devices #1 Primary 374.00' 24.0" Round 102 If @ 3.92 L= 102.0' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 374.00' / 370.00' S= 0.0392 '/' Cc= 0.900 n= 0.020, Flow Area= 3.14 sf #2 Device 1 385.10' 8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 386.50' 12.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Device 1 389.30' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Secondary 391.00' 8.0' long x 16.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=8.86 cfs @ 12.16 hrs HW=389.19' (Free Discharge) t1=102 If @ 3.92 (Passes 8.86 cfs of 48.17 cfs potential flow) 2=Orifice/Grate (Orifice Controls 3.26 cfs @ 9.33 fps) 3=Orifice/Grate (Orifice Controls 5.60 cfs @ 7.13 fps) =Orifice/Grate ( Controls 0.00 cfs) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=385.10' (Free Discharge) t5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM2 Prepared by HP Inc. Type/1 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Hydrograph ❑ Inflow ❑ Outflow ❑ Primary ❑ Secondary 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Time (hours) Dunlora WPO-SWM2 Type 1124-hr 25-yrRainfall=6.67" Prepared by HP Inc. Printed 12/6/2021 HvdroCADO 10.10-6a s/n 08126 © 2020 HvdroCAD Software Solutions LLC Paoe 26 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Subcatchment 1S: DA-Post Runoff Area=4.660 ac 0.00% Impervious Runoff Depth>4.09" Tc=8.0 min CN=80 Runoff=32.68 cfs 1.588 of Subcatchment 4S: DA-Pre Runoff Area=6.960 ac 0.00% Impervious Runoff Depth>2.23" Tc=10.5 min CN=61 Runoff=25.27 cfs 1.296 of Subcatchment 7S: DA-Offsite Runoff Area=0.960 ac 0.00% Impervious Runoff Depth>3.88" Tc=8.0 min CN=78 Runoff=6.45 cfs 0.311 of Pond 6P: Lvl 1 Onsite Ext'd Detention Peak Elev=389.80' Storage=33,837 cf Inflow=39.13 cfs 1.899 of Primary=24.34 cfs 1.862 of Secondary=0.00 cfs 0.000 of Outflow=24.34 cfs 1.862 of Total Runoff Area = 12.580 ac Runoff Volume = 3.195 of Average Runoff Depth = 3.05" 100.00% Pervious = 12.580 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM2 Prepared by HP Inc. Type 11 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Subcatchment 1 S: DA-Post Runoff = 32.68 cfs @ 11.99 hrs, Volume= 1.588 af, Depth> 4.09" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25-yr Rainfall=6.67" Area (ac) CN Description 4.660 80 4.660 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 1S: DA-Post Hydrograph 36 34 32 30 28 26 24 22 20 3 18 0 E ,6 10 8 6 4 2 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Dunlora WPO-SWM2 Prepared by HP Inc. Type 11 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Pre Runoff = 25.27 cfs @ 12.03 hrs, Volume= 1.296 af, Depth> 2.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25-yr Rainfall=6.67" Area (ac) CN Description ' 1.180 61 ' 1.540 61 : � n•n r_n 6.960 61 Weighted Average 6.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.5 Direct Entry, Subcatchment 4S: DA-Pre Hydrograph 0 LL ' M---- .....-MM...MwMM Id 5 8 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Duniora WPO-SWM2 Prepared by HP Inc. Type II 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Subcatchment 7S: DA-Offsite Runoff = 6.45 cfs @ 11.99 hrs, Volume= 0.311 af, Depth> 3.88" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25-yr Rainfall=6.67" Area (ac) CN Description 0.960 78 0.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 7S: DA-Mite Hydrograph ■ Runoff 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM2 Prepared by HIP Inc. Type Il 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Top of Berm 386.67 Inflow Area = 5.620 ac, 0.00% Impervious, Inflow Depth > 4.05" for 25-yr event Inflow = 39.13 cfs @ 11.99 hrs, Volume= 1.899 of Outflow = 24.34 cfs @ 12.09 hrs, Volume= 1.862 af, Atten= 38%, Lag= 5.8 min Primary = 24.34 cfs @ 12.09 hrs, Volume= 1.862 of Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 385.10' Surf.Area= 3,596 sf Storage= 6,801 cf Peak Elev= 389.80' @ 12.09 hrs Surf.Area= 7,447 sf Storage= 33,837 cf (27,036 cf above start) Plug -Flow detention time= 84.3 min calculated for 1.706 of (90% of inflow) Center -of -Mass det. time= 34.4 min ( 806.1 - 771.7 ) Volume Invert Avail.Storage Storage Description #1 380.00' 52,059 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 380.00 243 0 0 382.00 683 926 926 384.00 2,074 2,757 3,683 386.00 4,841 6,915 10,598 388.00 6,161 11,002 21,600 390.00 7,591 13,752 35,352 392.00 9,116 16,707 52,059 Device Routing Invert Outlet Devices #1 Primary 374.00' 24.0" Round 102 If @ 3.92 L= 102.0' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 374.00' / 370.00' S= 0.0392 '/' Cc= 0.900 n= 0.020, Flow Area= 3.14 sf #2 Device 1 385.10' 8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 386.50' 12.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Device 1 389.30' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Secondary 391.00' 8.0' long x 16.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=23.52 cfs @ 12.09 hrs HW=389.78' (Free Discharge) t1=102 If @ 3.92 (Passes 23.52 cfs of 48.99 cfs potential flow) 2=Orifice/Grate (Orifice Controls 3.50 cfs @ 10.04 fps) 3=Orifice/Grate (Orifice Controls 6.31 cfs @ 8.03 fps) =Orifice/Grate (Weir Controls 13.71 cfs @ 2.27 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=385.10' (Free Discharge) t5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM2 Prepared by HP Inc. Type 11 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Hydrograph ■ Inflow ❑ Outflow ❑ Primary ❑ Secondary 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM2 Type 1124-hr 100-yrRainfall=8.90" Prepared by HP Inc. Printed 12/6/2021 HvdroCADO 10.10-6a s/n 08126 © 2020 HvdroCAD Software Solutions LLC Paoe 32 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Subcatchment 1S: DA-Post Runoff Area=4.660 ac 0.00% Impervious Runoff Depth>6.06" Tc=8.0 min CN=80 Runoff=47.22 cfs 2.353 of Subcatchment 4S: DA-Pre Runoff Area=6.960 ac 0.00% Impervious Runoff Depth>3.80" Tc=10.5 min CN=61 Runoff=42.86 cfs 2.202 of Subcatchment 7S: DA-Offsite Runoff Area=0.960 ac 0.00% Impervious Runoff Depth>5.82" Tc=8.0 min CN=78 Runoff=9.44 cfs 0.466 of Pond 6P: Lvl 1 Onsite Ext'd Detention Peak Elev=390.29' Storage=37,574 cf Inflow=56.66 cfs 2.818 of Primary=48.83 cfs 2.771 of Secondary=0.00 cfs 0.000 of Outflow=48.83 cfs 2.771 of Total Runoff Area = 12.580 ac Runoff Volume = 5.020 of Average Runoff Depth = 4.79" 100.00% Pervious = 12.580 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Subcatchment 1 S: DA-Post Runoff = 47.22 cfs @ 11.99 hrs, Volume= 2.353 af, Depth> 6.06" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=8.90" a (ac) CN 4.660 80 4.660 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, Subcatchment 1S: DA-Post Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Pre Runoff = 42.86 cfs @ 12.02 hrs, Volume= 2.202 af, Depth> 3.80" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=8.90" Area (ac) CN Description 1.180 61 1.540 61 > A �An 1n 6.960 61 Weighted Average 6.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.5 Direct Entry, Subcatchment 4S: DA-Pre Hydrograph ■ 1111 ■ 1111 ■ J 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Duniora WPO-SWM2 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Subcatchment 7S: DA-Offsite Runoff = 9.44 cfs @ 11.99 hrs, Volume= 0.466 af, Depth> 5.82" Routed to Pond 6P : Lvl 1 Onsite Ext'd Detention w/R-Reduction Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100-yr Rainfall=8.90" Area (ac) CN 0.960 78 0.960 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.0 Direct Entry, 10 9 8 7 6 V 0 5 LL 4 3 2 1 0 Subcatchment 7S: DA-Mite Hydrograph Time (hours) ■ Rurwff Dunlora WPO-SWM2 Prepared by HIP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Top of Berm 386.67 Inflow Area = 5.620 ac, 0.00% Impervious, Inflow Depth > 6.02" for 100-yr event Inflow = 56.66 cfs @ 11.99 hrs, Volume= 2.818 of Outflow = 48.83 cfs @ 12.04 hrs, Volume= 2.771 af, Atten= 14%, Lag= 2.8 min Primary = 48.83 cfs @ 12.04 hrs, Volume= 2.771 of Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 385.10' Surf.Area= 3,596 sf Storage= 6,801 cf Peak Elev= 390.29' @ 12.04 hrs Surf.Area= 7,811 sf Storage= 37,574 cf (30,773 cf above start) Plug -Flow detention time= 70.1 min calculated for 2.615 of (93% of inflow) Center -of -Mass det. time= 30.0 min ( 792.5 - 762.5 ) Volume Invert Avail.Storage Storage Description #1 380.00' 52,059 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 380.00 243 0 0 382.00 683 926 926 384.00 2,074 2,757 3,683 386.00 4,841 6,915 10,598 388.00 6,161 11,002 21,600 390.00 7,591 13,752 35,352 392.00 9,116 16,707 52,059 Device Routing Invert Outlet Devices #1 Primary 374.00' 24.0" Round 102 If @ 3.92 L= 102.0' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 374.00' / 370.00' S= 0.0392 '/' Cc= 0.900 n= 0.020, Flow Area= 3.14 sf #2 Device 1 385.10' 8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 386.50' 12.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Device 1 389.30' 48.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Secondary 391.00' 8.0' long x 16.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=49.32 cfs @ 12.04 hrs HW=390.26' (Free Discharge) t1=102 If @ 3.92 (Passes 49.32 cfs of 49.65 cfs potential flow) 2=Orifice/Grate (Orifice Controls 3.69 cfs @ 10.58 fps) 3=Orifice/Grate (Orifice Controls 6.83 cfs @ 8.70 fps) =Orifice/Grate (Weir Controls 38.80 cfs @ 3.21 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=385.10' (Free Discharge) t5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM2 Prepared by HP Inc. Type II 24-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Pond 6P: Lvl 1 Onsite Ext'd Detention w/R-Reduction Hydrograph ■ Inflow ■ Outflow ■ Primary ■ Secondary Time (hours)