Storm Water management Plan for parking lot improvements

Home Browse Search

r � 11586 SPENSA - ORONO Type 1124-hr 2 yr Rainfall=2.80" Prepared by{enter your company name here) Page 7 HydroCAD®8.00 s/n 000837 0 2006 HydroCAD Software Solutions LLC 5/18/2009 Pond RAIN G: POND 1 [93] Warning: Storage range exceeded by 0.08' [85] Warning: Oscillations may require Finer Routing>1 Inflow Area = 0.977 ac, Inflow Depth > 1.76" for 2 yr event Inflow = 2.73 cfs @ 12.01 hrs, Volume= 0.143 of Outflow = 0.15 cfs @ 13.70 hrs, Volume= 0.042 af, Atten= 95%, Lag= 101.3 min Discarded = 0.04 cfs @ 13.70 hrs, Volume= 0.033 of Primary = 0.10 cfs @ 13.70 hrs, Volume= 0.009 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 1,022.58' @ 13.70 hrs Surf.Area= 3,070 sf Storage=4,430 cf Plug-Flow detention time= 236.8 min calculated for 0.042 of(29% of inflow) Center-of-Mass det. time= 137.6 min (908.4- 770.7 ) Volume Invert Avail.Storage Storage Description #1 1,020.00' 4,430 cf Custom Stage Data(Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 1,020.00 530 0 0 1,021.00 1,500 1,015 1,015 1,022.00 2,530 2,015 3,030 1,022.50 3,070 1,400 4,430 Device Routing Invert Outlet Devices #1 Discarded 0.00' 0.600 in/hr Exfiltration over Horizontal area #2 Primary 1,022.50' 2.0' long x 5.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 Qiscarded OutFlow Max=0.04 cfs @ 13.70 hrs HW=1,022.58' (Free Discharge) '--1=Exfiitration (Exfiltration Controls 0.04 cfs) Primary OutFlow Max=0.10 cfs @ 13.70 hrs HW=1,022.58' (Free Discharge) t2=Broad-Crested Rectangular Weir (Weir Controls 0.10 cfs @ 0.66 fps)