Stormwater Runoff Calculator

Stormwater Runoff Calculator

Estimate the peak runoff rate using the Rational Method:
\[ Q = 1.008 \times C \times I \times A \] where: - \( C \) is the runoff coefficient, - \( I \) is the rainfall intensity (in/hr), and - \( A \) is the drainage area (acres).

* Enter values in SI units: coefficient (0–1), intensity (in/hr), and area (acres).

Step 1: Enter Parameters

Example: 0.5

Example: 2 in/hr

Example: 5 acres

Formula: \( Q = 1.008 \times C \times I \times A \)