Problems on flood forecasting in the semi-arid region

The characteristics of the semi-arid region are shortage of rainfall and the non uniformity of spatio temporal distribution.Conditions of catchment underlay differ from humid regions.It is difficult to forecast flood in the semi-arid region,which is non uniformity of infiltration capcity,computation of water content in surface soil,leakage calculation and non-unifority of rainfall.The preliminary methods for overcoming above difficulties are also discussed.