Channel Flow (Q) Calculator

Calculate the channel flow using Manning’s Equation:
$Q = \frac{1}{n} A R^{\frac{2}{3}} S^{\frac{1}{2}}$

* Enter the cross-sectional area $A$ (ft²), Manning’s roughness coefficient $n$ , hydraulic radius $R$ (ft), and channel slope $S$ (ft/ft).

Step 1: Enter Parameters

Cross-sectional Area,

A

(ft²):

Example: 50 ft²

Manning’s Roughness Coefficient,

n

Example: 0.015

Hydraulic Radius,

R

(ft):

Example: 3 ft

Channel Slope,

S

(ft/ft):

Example: 0.01 ft/ft