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THE FEUTEX TOOLKIT

Rational Method Peak Runoff

Estimate peak runoff and event volume under a constant-intensity assumption.

Civil Engineering workspace● Runs in your browser
01 Your input
02 Your result
View or copy raw result data
FormulaQ=C i A/360 for mm/h and hectares.
Sources and model references

Worked example

Inputs

Runoff coefficient
0.6
Rainfall intensity
50 mm/h
Catchment area
2 ha
Uniform rainfall duration
30 min

Expected results

Peak discharge estimate
0.1666666667 m³/s
Constant-intensity runoff volume
300 m³

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter every input in the labeled units; use measured or independently specified properties.
  2. Check the stated model assumptions before calculating.
  3. Interpret the output as a model estimate and verify it independently for the intended application.

Try this example

{
  "coefficient": 0.6,
  "intensity": 50,
  "area": 2,
  "duration": 30
}

Accuracy and scope

Small catchment rational-method assumptions; storm duration must meet time-of-concentration criteria. No rainfall frequency selection or hydrograph routing. Educational engineering estimate only; not structural or safety certification, equipment selection, or operating recommendations.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.