Identical linear reservoir model of geomorphologic instantaneous unit hydrograph: A review

Planning, design and management of water resources projects require proper estimation of runoff generated from particular catchment, to make the structures stable to dispose off high runoff volume safely. To accomplish this task, hydrologists apply different rainfall-runoff estimation models, which require estimation of different input parameters to be calculated from the data obtained from gauged basins. But for ungauged basins, geomorphological instantaneous unit hydrograph (GIUH) has proved to be an effective tool to predict the hydrologic response as it does not rely on the measured data sets. GIUH is derived from geomorphological characteristics of a basin and is said to be the link between hydrology and basin geomorphology. This paper discusses the systematic progress made by researchers in derivation of GIUH, the limitations emphasized and modifications suggested by different scientists in determination of various parameters of the linear reservoir model of GIUH, and application of linear reservoir model of GIUH to different watersheds.