Open Channel Flow Calculator (Manning's Equation)

Calculate discharge, velocity, hydraulic properties, or normal depth with Manning's equation for rectangular, trapezoidal, triangular, parabolic, and surveyed station/elevation channel shapes.

Input Parameters

Channel Shape

Flow Parameters

ft

Known water depth; discharge will be computed

ft/ft

Longitudinal slope of channel bed

Roughness coefficient for channel material

View Manning's n Reference Table

Channel Geometry

ft

Width of the channel bottom

Ready to Calculate

Enter your channel parameters and click Calculate to see results.

For educational purposes only. Not a substitute for professional engineering judgment.

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