Application of Three Parameter Muskingum Method on Karun River

An efficient modification of the Muskingum method of flood routing has been verified, which yields the coefficients of Muskingum flood routing equation directly without the use of the graphical procedure. A simple conceptual model of lateral inflow has also been incorporated to account for any lateral inflow or outflow that occurs in the given reach. The incorporation of lateral inflow has been considered through a lateral inflow parameter along with the standard storage and weighing parameters, K and x. It also presents a much effective and direct approach for estimating the routing coefficients for the Muskingum model. Application of this extended Muskingum method has been verified on Karun river of Iran and the respective 6-h hydrograph has been plotted. It showed that the usual curb on the routing coefficients to sum to unity is not applicable in case of lateral inflow. The estimated outputs showed close correlation with the observed outflow.