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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 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.

Key differences

Culvert Design CalculatorCulvert Sizing Calculator
CategoryCivilCivil
Inputs required54
ResultRequired Culvert Diameter (m)Required Culvert Diameter (inches)
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 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.