Flo-Well Calculator
Calculation based on 1” of water volume. Multiply the number of recommended Flo-Wells by the number of inches of expected water. View the US 100-year rainfall map.
Step 1:
Enter the length in feet of your drainage area

Enter the width in feet of your drainage area
Step 2: 
Select the surface of your Drainage Area
Step 3:
Select the material used as backfill
Step 4: 
Enter the diameter in feet of the backfill material
Step 5: 
Select the soil type under the Flo-Well
Step 6:
Press the Calculate button for results
Step 7:
View your results below
 
Formulas:
Number of Flo-Wells to use per Drainage Area =
[Water Runoff Volume into Flo-Well]
X Coefficient of Ground Under Flo-Well]
[Volume of Flo-Well (7.527ft3)] + Volume of Backfill Material]
Water Runoff Volume =
(Sq. Ft. Area X Coefficient of Runoff)
12
Volume of Backfill Material =
3.14/4 X (Diameter of Backfill Material2
- Diameter of Flow-Well2)
X
Depth of Flow-Well
X (1-Coefficient of Runoff for Backfill Material)