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THE FEUTEX TOOLKIT

Manning Trapezoidal Channel

Estimate uniform-flow area, hydraulic radius, discharge and velocity.

Hydraulics workspace● Runs in your browser
01 Your input
02 Your result
View or copy raw result data
FormulaQ=(1/n)AR^(2/3)S^(1/2), SI formulation.
Sources and model references

Worked example

Inputs

Bottom width
2 m
Water depth
1 m
Side slope horizontal per vertical
1
Energy slope
0.001 m/m
Manning roughness
0.03 s/m^(1/3)

Expected results

Flow area
3 m²
Hydraulic radius
0.6213203436 m
Discharge
2.30255696 m³/s

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter every input in the labeled units; use measured or independently specified properties.
  2. Check the stated model assumptions before calculating.
  3. Interpret the output as a model estimate and verify it independently for the intended application.

Try this example

{
  "bottom": 2,
  "depth": 1,
  "side": 1,
  "slope": 0.001,
  "n": 0.03
}

Accuracy and scope

Steady uniform free-surface flow; supplied roughness is site-specific and not selected by this tool. Educational engineering estimate only; not structural or safety certification, equipment selection, or operating recommendations.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.