Rational Method Runoff
Calculate peak stormwater discharge using the Rational Method (Q = CIA/360). Estimate runoff from rainfall intensity, runoff coefficient, and catchment area.
Inputs
Results
Peak Discharge
0.694 m³/s
Peak Discharge
694.44 L/s
How to Use This Calculator
- Enter Rainfall Intensity, Runoff Coefficient (C), and Catchment Area.
- Review Peak Discharge (m³/s) and Peak Discharge (L/s).
- Use Peak Discharge (Imperial) (cfs) and Flow Rate (GPM) to inform your decision.
- Use the chart to visualize the results and explore different scenarios by adjusting inputs.
Formula
Q = C × I × A / 360Related Calculators
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