SW6211001_Design Calculations (DA, Pond 1)_20211014

Wayside Apartments Required Storm Volume
Pond #1
Drainage Area:
300,353 sf (6.90 acres)
Impervious Area: 188,578 sf (4.33 ac)
Impervious: 62.8%
1 inch Storm Event:
Rv = 0.05+0.009 1
Rv = runoff coefficient
1= percent impervious
Rv=0.05+0.009*62.8%
= 0.6152
For volume that must be controlled:
Volume=3,630*Rd*Rv*A
Volume = 3,630*(1 inch)*(0.615)*6.90 acres = 15,404 cf
SA/DA ratio is 2.21 for a depth of 3 feet
Required surface area = 6.90 ac * (.0221) = 0.152 ac or 6,621 sf
Surface area provided = 12,704 sf
409 Chicago Drive, Suite 112, FayetteviIle. NC 28306
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