The image above represents discharge | slope area method.

To compute for discharge | slope area method, four essential parameters are needed and these parameters are **Manning’s Co-efficient (N), Area (A), Hydraulic Radius (R)** and** Slope (S).**

The formula for calculating discharge | slope area method:

Q = (^{A} / _{N}) R^{2/3} S^{1/2}

Where;

Q = Discharge

N = Manning’s Co-efficient

A = Area

R = Hydraulic Radius

S = Slope

Let’s solve an example;

Find the discharge when the manning’s co-efficient is 4, the area is 30, the hydraulic radius is 15 and the slope is 22.

This implies that;

N = Manning’s Co-efficient = 4

A = Area = 30

R = Hydraulic Radius = 15

S = Slope = 22

Q = (^{A} / _{N}) R^{2/3} S^{1/2}

Q = (^{30} / _{4}) (15)^{2/3} (22)^{1/2}

Q = (7.5) (6.08) (4.69)

Q = 213.96

Therefore, the **discharge** is **213.96.**

Continue reading How to Calculate and Solve for Discharge | Slope Area Method | Water Budget