Flood Frequency Analysis
Estimate the design flood discharge for a given return period using a simplified log-Pearson Type III frequency analysis.
Inputs
Results
Design Discharge
293 m³/s
Annual Exceedance Probability
1%
How to Use This Calculator
- Enter Mean Annual Peak Flow, Standard Deviation, and Return Period.
- Set Skew Coefficient.
- Review Design Discharge (m³/s) and Annual Exceedance Probability (%).
- Use Non-Exceedance Probability (%) and Frequency Factor (K) to inform your decision.
- Use the chart to visualize the results and explore different scenarios by adjusting inputs.
Formula
log Q = log μ + K × log σ (Log-Pearson Type III)Related Calculators
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