Floods can play great havoc including loss of life, damage to property and agricultural crops, health hazards and disruption of human. The information such as peak flow and its volume are required in the design phase of irrigation, hydro-power and flood control projects. Hydrological models are widely used for the computation of flows in response of precipitation in the catchment and help to understand the characteristics behavior of a stream over a long period of time. The inputs for such models include long term records of stream flow, meteorological data and catchment characteristics. This book includes hydrological analysis of the Kanshi River catchment in Pakistan using TOPMODEL. The model predicts catchment water discharge and spatial soil water saturation pattern based on precipitation and evapo-transpiration time series and topographic information. The results of this study may be helpful to hydrologists, engineers and policy makers in water resources field.