Compare calculators
Both calculators run independently β change the inputs on either side to compare results.
Civil
Storm Water Runoff Calculator
Estimate peak stormwater runoff flow from a drainage basin using the Rational Method. Ideal for sizing storm drains, culverts, and detention ponds for small urban and suburban catchments under 200 acres.
Fill in the required fields to see your result.
Civil
Storm Water Drainage Calculator
Estimate peak stormwater runoff and determine the minimum pipe diameter needed to handle it. Used by civil engineers and drainage designers when sizing pipes for subdivisions, roads, or urban catchments.
Fill in the required fields to see your result.
Key differences
| Storm Water Runoff Calculator | Storm Water Drainage Calculator | |
|---|---|---|
| Category | Civil | Civil |
| Inputs required | 3 | 5 |
| Result | Peak Runoff Flow (cfs) | Required Pipe Diameter (mm) |
| What it does | Estimate peak stormwater runoff flow from a drainage basin using the Rational Method. Ideal for sizing storm drains, culverts, and detention ponds for small urban and suburban catchments under 200 acres. | Estimate peak stormwater runoff and determine the minimum pipe diameter needed to handle it. Used by civil engineers and drainage designers when sizing pipes for subdivisions, roads, or urban catchments. |