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HomeMy WebLinkAboutWPO202100063 Stormwater Management Maintenance Agree. 2021-12-06 (3)4S 8S 5S DA-Swm3 Runoff eduction Pre -Developed Wateshed 4P Lvl 1 Ext'd Detention Subcat Reach Aon Link Dunlora WPO-SWM3 Prepared by HP Inc. Project Notes Defined 10 rainfall events from Albemarle Rainfall OF Printed 12/6/2021 Dunlora WPO-SWM3 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 50-yr Type II 24-hr Default 24.00 1 7.73 2 6 100-yr Type II 24-hr Default 24.00 1 8.90 2 Printed 12/6/2021 Dunlora WPO-SWM3 Prepared by HP Inc. Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 20.940 79 (4S, 8S) 14.570 61 (5S) 35.510 72 TOTAL AREA Printed 12/6/2021 Dunlora WPO-SWM3 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 35.510 Other 4S, 5S, 8S 35.510 TOTAL AREA Printed 12/6/2021 Dunlora WPO-SWM3 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 35.510 35.510 4S, 5S, 8S 0.000 0.000 0.000 0.000 35.510 35.510 TOTAL AREA Dunlora WPO-SWM3 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 4P 368.00 361.00 117.3 0.0597 0.020 0.0 42.0 0.0 Dunlora WPO-SWM3 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 4S: DA-Swm3 Runoff Area=14.620 ac 0.00% Impervious Runoff Depth>1.06" Tc=12.0 min CN=79 Runoff=24.00 cfs 1.291 of Subcatchment 5S: Pre -Developed Runoff Area=14.570 ac 0.00% Impervious Runoff Depth>0.30" Tc=19.4 min CN=61 Runoff=3.41 cfs 0.362 of Subcatchment 8S: Runoff Reduction Runoff Area=6.320 ac 0.00% Impervious Runoff Depth>1.06" Tc=10.0 min CN=79 Runoff=11.09 cfs 0.558 of Pond 4P: Lvl 1 Ext'd Detention Peak Elev=377.30' Storage=86,054 cf Inflow=34.88 cfs 1.849 of Primary=1.26 cfs 0.830 of Secondary=0.00 cfs 0.000 of Outflow=1.26 cfs 0.830 of Total Runoff Area = 35.510 ac Runoff Volume = 2.211 of Average Runoff Depth = 0.75" 100.00% Pervious = 35.510 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Swm3 Runoff = 24.00 cfs @ 12.05 hrs, Volume= 1.291 af, Depth> 1.06" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 14.620 79 14.620 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Subcatchment 4S: DA-Swm3 Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Summary for Subcatchment 5S: Pre -Developed Wateshed Runoff = 3.41 cfs @ 12.18 hrs, Volume= 0.362 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 8.570 61 4.580 61 1.420 61 14.570 61 Weighted Average 14.570 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 19.4 Direct Entry, Subcatchment 5S: Pre -Developed Wateshed Hydrograph ❑ RunoH 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Duniora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 M --- „ Summary for Subcatchment 8S: Runoff Reduction Runoff = 11.09 cfs @ 12.02 hrs, Volume= 0.558 af, Depth> 1.06" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 6.320 79 6.320 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Reduction Hydrograph 1 1 1 1 C 1 1 1 1 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Dunlora WPO-SWM3 Prepared by HIP Inc. Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 Summary for Pond 4P: Lvl 1 Ext'd Detention Inflow Area = 20.940 ac, 0.00% Impervious, Inflow Depth > 1.06" for 1-yr event Inflow = 34.88 cfs @ 12.04 hrs, Volume= 1.849 of Outflow = 1.26 cfs @ 15.20 hrs, Volume= 0.830 af, Atten= 96%, Lag= 189.6 min Primary = 1.26 cfs @ 15.20 hrs, Volume= 0.830 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= 374.00' Surf.Area= 11,021 sf Storage= 35,211 cf Peak Elev= 377.30' @ 15.20 hrs Surf.Area= 17,296 sf Storage= 86,054 cf (50,843 cf above start) Plug -Flow detention time= 539.3 min calculated for 0.021 of (1% of inflow) Center -of -Mass det. time= 152.6 min ( 956.7 - 804.1 ) Volume Invert Avail.Storage Storage Description #1 368.00' 169,566 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 368.00 2,576 0 0 372.00 6,346 17,844 17,844 374.00 11,021 17,367 35,211 376.00 17,296 28,317 63,528 378.00 17,296 34,592 98,120 380.00 17,296 34,592 132,712 382.00 19,558 36,854 169,566 Device Routing Invert Outlet Devices #1 Primary 368.00' 42.0" Round Culvert L= 117.3' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 368.00' / 361.00' S= 0.0597 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 9.62 sf #2 Device 1 374.00' 3.0" Vert. Orifice/Grate X 3.00 C= 0.600 Limited to weir flow at low heads #3 Device 1 378.60' 60.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 379.70' 15.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=1.26 cfs @ 15.20 hrs HW=377.30' (Free Discharge) t1=Culvert (Passes 1.26 cfs of 112.33 cfs potential flow) �2=Orifice/Grate (Orifice Controls 1.26 cfs @ 8.58 fps) 3=Orifice/Grate ( Controls 0.00 cfs) econdary OutFlow Max=0.00 cfs @ 5.00 hrs HW=374.00' (Free Discharge) =Broad -Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM3 Prepared by HP Inc. Pond 4P: Lvl 1 Ext'd Detention Hydrograph Type 1124-hr 1-yrRainfall=2.97" Printed 12/6/2021 ■ Inflow ❑ Outflow ❑ Primary ❑ Secondary 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM3 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 4S: DA-Swm3 Runoff Area=14.620 ac 0.00% Impervious Runoff Depth>1.50" Tc=12.0 min CN=79 Runoff=33.93 cfs 1.823 of Subcatchment 5S: Pre -Developed Runoff Area=14.570 ac 0.00% Impervious Runoff Depth>0.53" Tc=19.4 min CN=61 Runoff=7.62 cfs 0.644 of Subcatchment 8S: Runoff Reduction Runoff Area=6.320 ac 0.00% Impervious Runoff Depth>1.50" Tc=10.0 min CN=79 Runoff=15.66 cfs 0.789 of Pond 4P: Lvl 1 Ext'd Detention Peak Elev=378.64' Storage=109,250 cf Inflow=49.28 cfs 2.612 of Primary=2.01 cfs 1.067 of Secondary=0.00 cfs 0.000 of Outflow=2.01 cfs 1.067 of Total Runoff Area = 35.510 ac Runoff Volume = 3.256 of Average Runoff Depth = 1.10" 100.00% Pervious = 35.510 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 2-yr Rainfall=3.59 " Printed 12/6/2021 Summary for Subcatchment 4S: DA-Swm3 Runoff = 33.93 cfs @ 12.04 hrs, Volume= 1.823 af, Depth> 1.50" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 14.620 79 14.620 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Subcatchment 4S: DA-Swm3 Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 2-yr Rainfall=3.59 " Printed 12/6/2021 Summary for Subcatchment 5S: Pre -Developed Wateshed Runoff = 7.62 cfs @ 12.16 hrs, Volume= 0.644 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 8.570 61 4.580 61 1.420 61 14.570 61 Weighted Average 14.570 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 19.4 Direct Entry, Subcatchment 5S: Pre -Developed Wateshed Hydrograph ❑ Runoff 8 ] 62 cis Type 11 24-hr 2-yr Rainfall=3.59" 6 Runoff Area=14.570 ac Runoff Volume=0.644 of 5 Runoff Depth>0.53" LL - Tc=19.4 min 3 CN=61 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Duniora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 2-yr Rainfall=3.59 " Printed 12/6/2021 Summary for Subcatchment 8S: Runoff Reduction Runoff = 15.66 cfs @ 12.02 hrs, Volume= 0.789 af, Depth> 1.50" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 6.320 79 6.320 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Reduction Hydrograph ■ Rurwff 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM3 Prepared by HIP Inc. Type 1124-hr 2-yrRainfall=3.59" Printed 12/6/2021 Summary for Pond 4P: Lvl 1 Ext'd Detention Inflow Area = 20.940 ac, 0.00% Impervious, Inflow Depth > 1.50" for 2-yr event Inflow = 49.28 cfs @ 12.03 hrs, Volume= 2.612 of Outflow = 2.01 cfs @ 14.28 hrs, Volume= 1.067 af, Atten= 96%, Lag= 134.5 min Primary = 2.01 cfs @ 14.28 hrs, Volume= 1.067 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= 374.00' Surf.Area= 11,021 sf Storage= 35,211 cf Peak Elev= 378.64' @ 14.28 hrs Surf.Area= 17,296 sf Storage= 109,250 cf (74,039 cf above start) Plug -Flow detention time= 451.5 min calculated for 0.259 of (10% of inflow) Center -of -Mass det. time= 152.1 min ( 949.1 - 797.0 ) Volume Invert Avail.Storage Storage Description #1 368.00' 169,566 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 368.00 2,576 0 0 372.00 6,346 17,844 17,844 374.00 11,021 17,367 35,211 376.00 17,296 28,317 63,528 378.00 17,296 34,592 98,120 380.00 17,296 34,592 132,712 382.00 19,558 36,854 169,566 Device Routing Invert Outlet Devices #1 Primary 368.00' 42.0" Round Culvert L= 117.3' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 368.00' / 361.00' S= 0.0597 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 9.62 sf #2 Device 1 374.00' 3.0" Vert. Orifice/Grate X 3.00 C= 0.600 Limited to weir flow at low heads #3 Device 1 378.60' 60.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 379.70' 15.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=1.97 cfs @ 14.28 hrs HW=378.64' (Free Discharge) t1=Culvert (Passes 1.97 cfs of 121.90 cfs potential flow) �2=Orifice/Grate (Orifice Controls 1.51 cfs @ 10.24 fps) 3=Orifice/Grate (Weir Controls 0.47 cfs @ 0.68 fps) econdary OutFlow Max=0.00 cfs @ 5.00 hrs HW=374.00' (Free Discharge) =Broad -Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM3 Prepared by HP Inc. Pond 4P: Lvl 1 Ext'd Detention Hydrograph Type 1124-hr 2-yr Rainfall=3.59 " Printed 12/6/2021 ■ Inflow ❑ Outflow ❑ Primary ❑ Secondary 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM3 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 4S: DA-Swm3 Runoff Area=14.620 ac 0.00% Impervious Runoff Depth>2.94" Tc=12.0 min CN=79 Runoff=65.60 cfs 3.579 of Subcatchment 5S: Pre -Developed Runoff Area=14.570 ac 0.00% Impervious Runoff Depth>1.46" Tc=19.4 min CN=61 Runoff=25.02 cfs 1.772 of Subcatchment 8S: Runoff Reduction Runoff Area=6.320 ac 0.00% Impervious Runoff Depth>2.94" Tc=10.0 min CN=79 Runoff=30.22 cfs 1.548 of Pond 4P: Lvl 1 Ext'd Detention Peak Elev=379.65' Storage=126,743 cf Inflow=95.19 cfs 5.128 of Primary=57.35 cfs 3.448 of Secondary=0.00 cfs 0.000 of Outflow=57.35 cfs 3.448 of Total Runoff Area = 35.510 ac Runoff Volume = 6.900 of Average Runoff Depth = 2.33" 100.00% Pervious = 35.510 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM3 Prepared by HP Inc. Type/1 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Swm3 Runoff = 65.60 cfs @ 12.04 hrs, Volume= 3.579 af, Depth> 2.94" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 14.620 79 14.620 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Subcatchment 4S: DA-Swm3 Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HP Inc. Type II 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Subcatchment 5S: Pre -Developed Wateshed Runoff = 25.02 cfs @ 12.14 hrs, Volume= 1.772 af, Depth> 1.46" 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 8.570 61 4.580 61 1.420 61 14.570 61 Weighted Average 14.570 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 19.4 Direct Entry, Subcatchment 5S: Pre -Developed Wateshed Hydrograph too e[i . I, MMMMMM j M 0Y 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Duniora WPO-SWM3 Prepared by HP Inc. Type/1 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Subcatchment 8S: Runoff Reduction Runoff = 30.22 cfs @ 12.01 hrs, Volume= 1.548 af, Depth> 2.94" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 6.320 79 6.320 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Reduction Hydrograph ' __ -_—_ ---MMMM — 5 6 7 8 9 10.. 11 12....13....14 15 16.... 17.... 18....19....20 Time (hours) ■ Rurwff Dunlora WPO-SWM3 Prepared by HIP Inc. Type II 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Summary for Pond 4P: Lvl 1 Ext'd Detention Inflow Area = 20.940 ac, 0.00% Impervious, Inflow Depth > 2.94" for 10-yr event Inflow = 95.19 cfs @ 12.03 hrs, Volume= 5.128 of Outflow = 57.35 cfs @ 12.15 hrs, Volume= 3.448 af, Atten= 40%, Lag= 7.3 min Primary = 57.35 cfs @ 12.15 hrs, Volume= 3.448 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= 374.00' Surf.Area= 11,021 sf Storage= 35,211 cf Peak Elev= 379.65' @ 12.15 hrs Surf.Area= 17,296 sf Storage= 126,743 cf (91,532 cf above start) Plug -Flow detention time= 161.3 min calculated for 2.640 of (51 % of inflow) Center -of -Mass det. time= 48.5 min ( 831.0 - 782.5 ) Volume Invert Avail.Storage Storage Description #1 368.00' 169,566 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 368.00 2,576 0 0 372.00 6,346 17,844 17,844 374.00 11,021 17,367 35,211 376.00 17,296 28,317 63,528 378.00 17,296 34,592 98,120 380.00 17,296 34,592 132,712 382.00 19,558 36,854 169,566 Device Routing Invert Outlet Devices #1 Primary 368.00' 42.0" Round Culvert L= 117.3' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 368.00' / 361.00' S= 0.0597 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 9.62 sf #2 Device 1 374.00' 3.0" Vert. Orifice/Grate X 3.00 C= 0.600 Limited to weir flow at low heads #3 Device 1 378.60' 60.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 379.70' 15.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=56.93 cfs @ 12.15 hrs HW=379.65' (Free Discharge) t1=Culvert (Passes 56.93 cfs of 128.61 cfs potential flow) �2=Orifice/Grate (Orifice Controls 1.67 cfs @ 11.32 fps) 3=Orifice/Grate (Weir Controls 55.27 cfs @ 3.35 fps) econdary OutFlow Max=0.00 cfs @ 5.00 hrs HW=374.00' (Free Discharge) =Broad -Crested Rectangular Weir ( Controls 0.00 cfs) Dunlora WPO-SWM3 Prepared by HP Inc. Type Il 24-hr 10-yr Rainfall=5.43" Printed 12/6/2021 Pond 4P: Lvl 1 Ext'd Detention Hydrograph Time (hours) ❑ Inflow ❑ Outflow ❑ Primary ❑ Secondary Dunlora WPO-SWM3 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 4S: DA-Swm3 Runoff Area=14.620 ac 0.00% Impervious Runoff Depth>3.98" Tc=12.0 min CN=79 Runoff=87.74 cfs 4.850 of Subcatchment 5S: Pre -Developed Runoff Area=14.570 ac 0.00% Impervious Runoff Depth>2.23" Tc=19.4 min CN=61 Runoff=39.20 cfs 2.703 of Subcatchment 8S: Runoff Reduction Runoff Area=6.320 ac 0.00% Impervious Runoff Depth>3.98" Tc=10.0 min CN=79 Runoff=40.40 cfs 2.098 of Pond 4P: Lvl 1 Ext'd Detention Peak Elev=380.14' Storage=135,061 cf Inflow=127.29 cfs 6.948 of Primary=99.49 cfs 5.146 of Secondary=11.44 cfs 0.108 of Outflow=110.93 cfs 5.253 of Total Runoff Area = 35.510 ac Runoff Volume = 9.651 of Average Runoff Depth = 3.26" 100.00% Pervious = 35.510 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM3 Prepared by HP Inc. Type 11 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Swm3 Runoff = 87.74 cfs @ 12.04 hrs, Volume= 4.850 af, Depth> 3.98" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 14.620 79 14.620 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Subcatchment 4S: DA-Swm3 Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HP Inc. Type 11 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Subcatchment 5S: Pre -Developed Wateshed Runoff = 39.20 cfs @ 12.13 hrs, Volume= 2.703 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 ' 8.570 61 ' 4.580 61 ' 1.420 61 14.570 61 Weighted Average 14.570 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 19.4 Direct Entry, Subcatchment 5S: Pre -Developed Wateshed Hydrograph 42 40 38 36 34 32 30 28 26 w 24 3 22 20 LL 18 i6 14 12 10 8 6 4 2 0 Tc= 19.4 Y 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Duniora WPO-SWM3 Prepared by HP Inc. Type 11 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Subcatchment 8S: Runoff Reduction Runoff = 40.40 cfs @ 12.01 hrs, Volume= 2.098 af, Depth> 3.98" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 6.320 79 6.320 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Reduction Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HIP Inc. Type II 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Summary for Pond 4P: Lvl 1 Ext'd Detention Inflow Area = 20.940 ac, 0.00% Impervious, Inflow Depth > 3.98" for 25-yr event Inflow = 127.29 cfs @ 12.03 hrs, Volume= 6.948 of Outflow = 110.93 cfs @ 12.09 hrs, Volume= 5.253 af, Atten= 13%, Lag= 3.8 min Primary = 99.49 cfs @ 12.09 hrs, Volume= 5.146 of Secondary = 11.44 cfs @ 12.09 hrs, Volume= 0.108 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 374.00' Surf.Area= 11,021 sf Storage= 35,211 cf Peak Elev= 380.14' @ 12.09 hrs Surf.Area= 17,449 sf Storage= 135,061 cf (99,850 cf above start) Plug -Flow detention time= 126.5 min calculated for 4.445 of (64% of inflow) Center -of -Mass det. time= 36.0 min ( 811.8 - 775.7 ) Volume Invert Avail.Storage Storage Description #1 368.00' 169,566 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 368.00 2,576 0 0 372.00 6,346 17,844 17,844 374.00 11,021 17,367 35,211 376.00 17,296 28,317 63,528 378.00 17,296 34,592 98,120 380.00 17,296 34,592 132,712 382.00 19,558 36,854 169,566 Device Routing Invert Outlet Devices #1 Primary 368.00' 42.0" Round Culvert L= 117.3' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 368.00' / 361.00' S= 0.0597 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 9.62 sf #2 Device 1 374.00' 3.0" Vert. Orifice/Grate X 3.00 C= 0.600 Limited to weir flow at low heads #3 Device 1 378.60' 60.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 379.70' 15.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=97.84 cfs @ 12.09 hrs HW=380.12' (Free Discharge) t1=Culvert (Passes 97.84 cfs of 131.62 cfs potential flow) �2=Orifice/Grate (Orifice Controls 1.74 cfs @ 11.79 fps) 3=Orifice/Grate (Weir Controls 96.10 cfs @ 4.03 fps) econdary OutFlow Max=10.71 cfs @ 12.09 hrs HW=380.12' (Free Discharge) =Broad -Crested Rectangular Weir (Weir Controls 10.71 cfs @ 1.70 fps) Dunlora WPO-SWM3 Prepared by HP Inc. Type ll 24-hr 25-yr Rainfall=6.67" Printed 12/6/2021 Pond 4P: Lvl 1 Ext'd Detention Hydrograph Time (hours) ■ Inflow ■ Outflow ■ Primary ■ Secondary Dunlora WPO-SWM3 Type 1124-hr 50-yrRainfall=7.73" Prepared by HP Inc. Printed 12/6/2021 HvdroCADO 10.10-6a s/n 08126 © 2020 HvdroCAD Software Solutions LLC Pace 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 4S: DA-Swm3 Runoff Area=14.620 ac 0.00% Impervious Runoff Depth>4.90" Tc=12.0 min CN=79 Runoff=106.85 cfs 5.968 of Subcatchment 5S: Pre -Developed Runoff Area=14.570 ac 0.00% Impervious Runoff Depth>2.94" Tc=19.4 min CN=61 Runoff=52.28 cfs 3.573 of Subcatchment 8S: Runoff Reduction Runoff Area=6.320 ac 0.00% Impervious Runoff Depth>4.90" Tc=10.0 min CN=79 Runoff=49.18 cfs 2.582 of Pond 4P: Lvl 1 Ext'd Detention Peak Elev=380.39' Storage=139,526 cf Inflow=154.98 cfs 8.550 of Primary=124.17 cfs 6.566 of Secondary=23.07 cfs 0.283 of Outflow=147.24 cfs 6.849 of Total Runoff Area = 35.510 ac Runoff Volume = 12.123 of Average Runoff Depth = 4.10" 100.00% Pervious = 35.510 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM3 Prepared by HP Inc. Type 11 24-hr 50-yr Rainfall= 7.73 " Printed 12/6/2021 Summary for Subcatchment 4S: DA-Swm3 Runoff = 106.85 cfs @ 12.04 hrs, Volume= 5.968 af, Depth> 4.90" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 50-yr Rainfall=7.73" Area (ac) CN 14.620 79 14.620 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Subcatchment 4S: DA-Swm3 Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HP Inc. Type 11 24-hr 50-yr Rainfall= 7.73 " Printed 12/6/2021 Summary for Subcatchment 5S: Pre -Developed Wateshed Runoff = 52.28 cfs @ 12.13 hrs, Volume= 3.573 af, Depth> 2.94" 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 50-yr Rainfall=7.73" Area (ac) CN Description 8.570 61 4.580 61 1.420 61 14.570 61 Weighted Average 14.570 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 19.4 Direct Entry, Subcatchment 5S: Pre -Developed Wateshed Hydrograph Fin-- ---- ..osm .. .- L �: 1 04004 -2 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ RunoH Duniora WPO-SWM3 Prepared by HP Inc. Type II 24-hr 50-yr Rainfall= 7.73 " Printed 12/6/2021 Summary for Subcatchment 8S: Runoff Reduction Runoff = 49.18 cfs @ 12.01 hrs, Volume= 2.582 af, Depth> 4.90" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 50-yr Rainfall=7.73" Area (ac) CN Description 6.320 79 6.320 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Reduction Hydrograph ■ Rurwff 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM3 Prepared by HIP Inc. Type II 24-hr 50-yr Rainfall= 7.73 " Printed 12/6/2021 Summary for Pond 4P: LA 1 Ext'd Detention Inflow Area = 20.940 ac, 0.00% Impervious, Inflow Depth > 4.90" for 50-yr event Inflow = 154.98 cfs @ 12.03 hrs, Volume= 8.550 of Outflow = 147.24 cfs @ 12.07 hrs, Volume= 6.849 af, Atten= 5%, Lag= 2.3 min Primary = 124.17 cfs @ 12.07 hrs, Volume= 6.566 of Secondary = 23.07 cfs @ 12.07 hrs, Volume= 0.283 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 374.00' Surf.Area= 11,021 sf Storage= 35,211 cf Peak Elev= 380.39' @ 12.07 hrs Surf.Area= 17,736 sf Storage= 139,526 cf (104,315 cf above start) Plug -Flow detention time= 111.8 min calculated for 6.041 of (71 % of inflow) Center -of -Mass det. time= 31.5 min ( 802.4 - 771.0 ) Volume Invert Avail.Storage Storage Description #1 368.00' 169,566 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 368.00 2,576 0 0 372.00 6,346 17,844 17,844 374.00 11,021 17,367 35,211 376.00 17,296 28,317 63,528 378.00 17,296 34,592 98,120 380.00 17,296 34,592 132,712 382.00 19,558 36,854 169,566 Device Routing Invert Outlet Devices #1 Primary 368.00' 42.0" Round Culvert L= 117.3' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 368.00' / 361.00' S= 0.0597 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 9.62 sf #2 Device 1 374.00' 3.0" Vert. Orifice/Grate X 3.00 C= 0.600 Limited to weir flow at low heads #3 Device 1 378.60' 60.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 379.70' 15.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=121.68 cfs @ 12.07 hrs HW=380.36' (Free Discharge) t1=Culvert (Passes 121.68 cfs of 133.14 cfs potential flow) �2=Orifice/Grate (Orifice Controls 1.77 cfs @ 12.02 fps) 3=Orifice/Grate (Weir Controls 119.91 cfs @ 4.34 fps) econdary OutFlow Max=21.67 cfs @ 12.07 hrs HW=380.36' (Free Discharge) =Broad -Crested Rectangular Weir (Weir Controls 21.67 cfs @ 2.19 fps) Dunlora WPO-SWM3 Prepared by HP Inc. 110 wn 100 90 LL 1 Type 1124-hr 50-yr Rainfall=7.73" Printed 12/6/2021 Pond 4P: Lvl 1 Ext'd Detention Hydrograph r Inflow Area=20.940 ac Peak Elev=380.39' Storage=139,526 cf 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Time (hours) ■ Inflow ■ Outflow ■ Pdmary ■ Secondary Dunlora WPO-SWM3 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 38 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 4S: DA-Swm3 Runoff Area=14.620 ac 0.00% Impervious Runoff Depth>5.93" Tc=12.0 min CN=79 Runoff=127.99 cfs 7.227 of Subcatchment 5S: Pre -Developed Runoff Area=14.570 ac 0.00% Impervious Runoff Depth>3.78" Tc=19.4 min CN=61 Runoff=67.61 cfs 4.594 of Subcatchment 8S: Runoff Reduction Runoff Area=6.320 ac 0.00% Impervious Runoff Depth>5.94" Tc=10.0 min CN=79 Runoff=58.90 cfs 3.126 of Pond 4P: Lvl 1 Ext'd Detention Peak Elev=380.64' Storage=143,936 cf Inflow=185.63 cfs 10.353 of Primary=135.24 cfs 8.105 of Secondary=36.17 cfs 0.542 of Outflow=171.39 cfs 8.646 of Total Runoff Area = 35.510 ac Runoff Volume = 14.947 of Average Runoff Depth = 5.05" 100.00% Pervious = 35.510 ac 0.00% Impervious = 0.000 ac Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Subcatchment 4S: DA-Swm3 Runoff = 127.99 cfs @ 12.03 hrs, Volume= 7.227 af, Depth> 5.93" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 14.620 79 14.620 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Subcatchment 4S: DA-Swm3 Hydrograph ■ Rurwff Time (hours) Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Subcatchment 5S: Pre -Developed Wateshed Runoff = 67.61 cfs @ 12.12 hrs, Volume= 4.594 af, Depth> 3.78" 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 8.570 61 4.580 61 1.420 61 14.570 61 Weighted Average 14.570 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 19.4 Direct Entry, Subcatchment 5S: Pre -Developed Wateshed Hydrograph I.-- ----- ® I------- ---� �.MMM 0 I/ ������`i■ .====ME AL "MMMMMMM 01 ---------'_---------------------------% 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Rurwff Duniora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Il.._.. Summary for Subcatchment 8S: Runoff Reduction Runoff = 58.90 cfs @ 12.01 hrs, Volume= 3.126 af, Depth> 5.94" Routed to Pond 4P : Lvl 1 Ext'd Detention 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 6.320 79 6.320 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Reduction Hydrograph ■ Rurwff 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Dunlora WPO-SWM3 Prepared by HIP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Summary for Pond 4P: Lvl 1 Ext'd Detention Inflow Area = 20.940 ac, 0.00% Impervious, Inflow Depth > 5.93" for 100-yr event Inflow = 185.63 cfs @ 12.03 hrs, Volume= 10.353 of Outflow = 171.39 cfs @ 12.07 hrs, Volume= 8.646 af, Atten= 8%, Lag= 2.3 min Primary = 135.24 cfs @ 12.07 hrs, Volume= 8.105 of Secondary = 36.17 cfs @ 12.06 hrs, Volume= 0.542 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 374.00' Surf.Area= 11,021 sf Storage= 35,211 cf Peak Elev= 380.64' @ 12.06 hrs Surf.Area= 18,015 sf Storage= 143,936 cf (108,725 cf above start) Plug -Flow detention time= 100.3 min calculated for 7.812 of (75% of inflow) Center -of -Mass det. time= 28.9 min ( 795.4 - 766.5 ) Volume Invert Avail.Storage Storage Description #1 368.00' 169,566 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 368.00 2,576 0 0 372.00 6,346 17,844 17,844 374.00 11,021 17,367 35,211 376.00 17,296 28,317 63,528 378.00 17,296 34,592 98,120 380.00 17,296 34,592 132,712 382.00 19,558 36,854 169,566 Device Routing Invert Outlet Devices #1 Primary 368.00' 42.0" Round Culvert L= 117.3' Box, 00 wingwalls, square crown edge, Ke= 0.700 Inlet / Outlet Invert= 368.00' / 361.00' S= 0.0597 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 9.62 sf #2 Device 1 374.00' 3.0" Vert. Orifice/Grate X 3.00 C= 0.600 Limited to weir flow at low heads #3 Device 1 378.60' 60.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 379.70' 15.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=134.69 cfs @ 12.07 hrs HW=380.61' (Free Discharge) t1=Culvert (Inlet Controls 134.69 cfs @ 14.00 fps) �2=Orifice/Grate (Passes < 1.81 cfs potential flow) 3=Orifice/Grate (Passes < 133.95 cfs potential flow) econdary OutFlow Max=34.83 cfs @ 12.06 hrs HW=380.61' (Free Discharge) =Broad -Crested Rectangular Weir (Weir Controls 34.83 cfs @ 2.54 fps) Dunlora WPO-SWM3 Prepared by HP Inc. Type 1124-hr 100-yr Rainfall=8.90" Printed 12/6/2021 Pond 4P: Lvl 1 Ext'd Detention Hydrograph ■ Inflow ■ Outflow ■ Primary ■ Secondary 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours)