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Rainfall Runoff Calculator

Estimate peak runoff, runoff volume, and runoff depth using the Rational Method, runoff coefficient volume, and the NRCS Curve Number method.

Peak Flow Runoff Volume Curve Number CSV Table

Runoff Estimator & Scenario Builder

Choose a method, enter your catchment area and storm inputs, and get peak discharge, runoff depth, and total runoff volume with unit conversions.

Drainage area

Area unit

Runoff coefficient (C)

Rain input type

Rainfall intensity

Intensity unit

Rainfall depth

Depth unit

Duration

Duration unit

Decimals

Export

Drainage area

Area unit

Rainfall depth

Depth unit

Runoff coefficient (C)

Add initial loss

Initial loss depth

Loss unit

Decimals

Export

Drainage area

Area unit

Rainfall depth (P)

Depth unit

Curve Number (CN)

Initial abstraction ratio

Decimals

Export

Scenario method

Range variable

Start value

End value

Step

Range unit

Max rows

Decimals

Export

Rainfall Runoff Calculator

Runoff Estimator & Scenario Builder

Peak flow (m³/s)

Peak flow (cfs)

Used intensity

Catchment size

Runoff volume (m³)

Runoff volume (liters)

Runoff volume (gallons)

Runoff depth

Runoff depth (mm)

Runoff depth (in)

Runoff volume (m³)

Effective runoff fraction

Rainfall Runoff Calculator

Runoff Estimator & Scenario Builder

Peak flow (m³/s)

Peak flow (cfs)

Used intensity

Catchment size

Runoff volume (m³)

Runoff volume (liters)

Runoff volume (gallons)

Runoff depth

Runoff depth (mm)

Runoff depth (in)

Runoff volume (m³)

Effective runoff fraction

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