Flash Flood Forecasting Model for Small Mountain Watershed

Small and medium sized rivers are usually in the mountain area, and lack. Flash flood is a frequent disaster phenomena in the small mountain watersheds, which often induces other natural disasters, such as landslide, debris flow and collapsing. Flood forecasting is one of the dominanting measures for flash flood mitigation, but there are challenges on forcasting the flash flood in these watersheds due to the lack of adquent hydrological observation and appropriate hydrologcial model. Flash flood could not be florecated effectively by employing the conventional flood forecasting model, such as the lumped hydrological model due to the lack of hydrological and other data. Based on the physically based distributed hydrological model framework, this paper proposed a flash flood forecasting model for small mountain watersheds. This model sets up the model spatial structure with satellite remotely sensed data and GIS technique, derives model parameters directly from the terrain properties, and optimize the parameters in data sparse catchments. The model has been tested in several southern China’s small watersheds including the data sparse and date plenty ones, and the results show that it is a good options for small mountain watersheds flash forecasting. Based on the super computers deployed in the author’s lab, the parallel computing algorithm for small watershed flash flood forecasting has been developed, and a cloud system for real-time forecasting has been set up.