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Civil

Culvert Sizing Calculator

Calculate the required culvert diameter to safely pass design stormwater flows under roads, driveways, or embankments. Helps engineers and contractors avoid undersized culverts that cause flooding or washouts.

Fill in the required fields to see your result.
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.

Key differences

Culvert Sizing CalculatorCulvert Design Calculator
CategoryCivilCivil
Inputs required45
ResultRequired Culvert Diameter (inches)Required Culvert Diameter (m)
What it doesCalculate the required culvert diameter to safely pass design stormwater flows under roads, driveways, or embankments. Helps engineers and contractors avoid undersized culverts that cause flooding or washouts.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.