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Civil

Culvert Design Calculator

Size a circular or box culvert to pass a design stormwater discharge using Manning's equation. Essential for highway engineers, drainage designers, and land developers ensuring roads stay clear during storm events.

Fill in the required fields to see your result.
Civil

Culvert Flow Calculator

Calculate the full-flow discharge capacity of a circular culvert using Manning's equation. Used by drainage engineers to check whether an existing or proposed culvert can pass a design flood without overtopping.

Fill in the required fields to see your result.

Key differences

Culvert Design CalculatorCulvert Flow Calculator
CategoryCivilCivil
Inputs required54
ResultRequired Culvert Diameter (m)Flow Rate (cfs)
What it doesSize a circular or box culvert to pass a design stormwater discharge using Manning's equation. Essential for highway engineers, drainage designers, and land developers ensuring roads stay clear during storm events.Calculate the full-flow discharge capacity of a circular culvert using Manning's equation. Used by drainage engineers to check whether an existing or proposed culvert can pass a design flood without overtopping.