Step 1:

Enter Square footage of drainage area:  sf

Step 2:

Choose the 25 Year Rainfall (see rainfall map).in/hr

Step 3:

Choose coefficient of Runoff  

Step 4:

Select EZ-Drain Size  

Step 5:

Press the Calculate button for results:


0 cubic feet per second
0 gallons per minute
Gallons to be stored: 0 gallons
Length of trench required: 0 ft
# EZFlow of 10-ft pieces required: 0
Gallons of storage provided: 0 gallons

Storage Volume (Gallons per 10-ft piece): 0
Flow Capacity (GPM at 1%): 0

Note: First Flush is defined as first 15 minutes of runoff. 15 minutes is the minimum length of time to be stored.
The first flush contains a higher proportion of oil, fertilizer, pesticides, etc. that get washed away with the rain.