Rainwater Runoff (or) Storm Water Runoff Calculator Using Rational Method
Rainwater Runoff Calculator
This is to calculate and store your property rainwater runoff.
in
sq.ft
Rainwater Runoff Formulas
Q = (C x I x A )/96.23
Where,
Q is the storm-water Run-off in Gallons Per Minute (GPM)
C is the Run-off coefficient
I is the Rainfall intensity in inches per hour
A is the Drainage Area in square feet
96.23 is a conversion factor when you want the flow rate in GPM and your driange area in square feet
Hundred Year Rainfall Map
The above maps shows the rainfall in inches