Watershed Bounded Network Model (WBNM) for Runoff Prediction of Large Basins

Applicability of a nonlinear version of the watershed bounded network model (WBNM) for large basins namely Shellbyville (1,246 km²), Columbia (3,129 km²), Centreville (5,304 km²) and Hurricane Mills (6,536 km²) of Duck River basin, to predict flood hydrograph based on rainfall excess hyetograph is investigated. Boyd et al. (1979) have applied this model for basins with areas ranging from 0.4 to 251 km² and recommended a constant value for the model parameter namely, c. In this investigation, c is found to vary from basin to basin and in a given basin it varies with rainfall excess volume. The effect of subdividing the basin into a finer mesh on the reproduction of the observed flood hydrograph is also investigated and the results discussed.