Broad Crested Weir Calculator  

Where,
q = Water Flow Rate
C_{d} = Discharge Constant
b = Width of the Weir
g = Gravity (9.81 m/s^{2})
h_{1}, h_{2} = Head 1 and Head 2 on the Weir
Example:
Calculate the Broad Crested Weir for the given details.
Width of the Weir (b) = 5 m
Head 1 on the Weir (h_{1}) = 3 m
Head 2 on the Weir (h_{2}) = 1 m
Discharge Constant (C_{d}) = 10
Solution:
Apply Formula:
q = C_{d} × b × h_{2} × (2g (h_{1}  h_{2})) ^{1/2
}Water Flow Rate (q) = 313.20919526731655 m^{3}/s