Numerical Modeling of Flood Propagation through System of Reservoirs

Abstract

An explicit numerical flow‐routing model is developed based on the second order McCormack scheme. This paper describes the use of the finite difference scheme for the solution of the St. Venant equations of the one‐dimensional unsteady open channel flow, and the treatment of the boundary problem by the method of characteristics. A case study is presented using the system of reservoirs and the fluvial network of tributaries of the left‐hand side of the Ebro River valley in Spain. To get an estimate of the regulating action provided by those reservoirs during the strong rainfall of the first days of November 1982, the registered inflow and outflow hydrographs are used for the simulation of the propagation of the waves along the watercourses. Results of flow computations are presented and compared with field measurements to show that this model can be considered a suitable technique for hydraulic studies involving rapidly varying flows.