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Civil

Culvert Flow Capacity Calculator

Estimate the full-flow discharge capacity of a circular culvert using Manning's equation. Used by civil engineers and hydrologists to size culverts for road crossings, drainage channels, and stormwater systems.

Fill in the required fields to see your result.
Civil

Pipe Flow Capacity Calculator

Determine water flow rate (in GPM) through circular pipes using Manning's equation. Used by civil engineers and plumbers to size pipes for gravity-fed drainage, sewer, and stormwater systems.

Fill in the required fields to see your result.

Key differences

Culvert Flow Capacity CalculatorPipe Flow Capacity Calculator
CategoryCivilCivil
Inputs required34
ResultFlow Capacity (cfs)Flow Capacity (gallons per minute)
What it doesEstimate the full-flow discharge capacity of a circular culvert using Manning's equation. Used by civil engineers and hydrologists to size culverts for road crossings, drainage channels, and stormwater systems.Determine water flow rate (in GPM) through circular pipes using Manning's equation. Used by civil engineers and plumbers to size pipes for gravity-fed drainage, sewer, and stormwater systems.