Runoff Prediction by Simple Tank Model Using Recession Curves

摘要

A simple water-tank model is constructed to simulate the rainfall-runoff process in a catchment. The water tank has a horizontal cross-sectional area, which is a function of the water depth and which may be determined from the recession curves of flood hydrographs. The total vertical depth of the water tank and the infiltration velocity, which govern the time lag between rainfall and runoff, are computed from the rising limbs of the flow hydrograph. The model is applied to two catchments, one in Japan and the other in the United States for predicting flood response to rainfall events. The results found from the tank model are in good agreement with the observed data. The parameters of the tank model have physical meanings of the catchment.