Q=1/n*R^(2/3)*S^(1/2)*A

n= manning coefficient
S=hydraulic gradient(m/m)
R=hydraulic radius(m)
A=area of section(m²)

n= R=
S= A=
Q= m³/s



 Q=1.49/n*R^(2/3)*S^(1/2)*A

n= manning coefficient
S=hydraulic gradient(ft/ft)
R=hydraulic radius(ft)
A=area of section(ft²)

n= R=
S= A=
Q= m³/s