Side weirs are widely used control structures in irrigation and drainage systems. The relationship between the discharge coefficient and flow, geometrical specifications of side weirs plays a vital role in estimation of discharge passing through the side weir. Generalized Reduced Gradient (GRG) technique is known to be a powerful optimization technique, it has therefore, been used in the present study to establish the relationship between discharge coefficient and flow, geometrical specifications of side weir. A comparative analysis of the equations developed by earlier researchers and present equation (GRG technique) on the basis of root mean square error (RMSE), percent bias (PBIAS) and Nash efficiency reveals that the discharge estimated using the discharge coefficients obtained by GRG technique was most accurate. Published laboratory data of flow through the side weirs was used in the present study.
Side weir, Discharge coefficient, GRG, Optimization
