Flood Routing Simulation and System Customization for a High-Leakage River Channel in China.

Leakage is a major factor impacting the evolution of flood in a highly permeable river. By integrating a mathematical model with data provided by a monitoring database, a flood routing system was developed for the Dagu River in China. The aim of this study was to calculate the leakage discharge and to discuss the effect of leakage for flood modeling within a high-leakage riverbed. This system was implemented for application of a flood-diversion experiment in 2003, which accessed data automatically and used estimated coefficients to calculate leakage discharge. The results showed that simulated discharge values fit well with the measured values, with an average relative error less than 10%, and the leakage average relative error was approximately 2%. The infiltration experiments showed that the leakage coefficient could be treated as a constant when the dynamics in the initial phase of a short flood event was stimulated. The initial water level and leakage and roughness coefficients were the main factors required to accurately determine the discharge of river seepage. [ABSTRACT FROM AUTHOR]