Development of GIUH for the Catchment Contributing to Loktak Lake, North East India

Abstract

Severity of flood damage is highly dependent on topography. In case of wetland, which includes altered water level regimes and linked with river system, estimation of flood is very important. However, substantial uncertainty exists in the precise estimation of river discharge when catchment is ungauged or partially gauged. This paper explores the river discharge of a partially gauged catchment contributing to Loktak Lake, an important wetland of North East India. Usually for the estimation of runoff response of an ungauged catchment resulting from a rainfall event, the geomorphological instantaneous unit hydrograph (GIUH) approach is very popular. In this paper, firstly an analysis has been performed to explore the geomorphologic parameters of the mentioned catchment and later on these geomorphological parameters coupled with Nakagami-m distribution to derive of GIUHs for various dynamic velocities. Moreover, these GIUHs are compared with another synthetic unit hydrograph (SUH) developed by Central Water Commission, Govt. of India (CWC) approach to find out the exact one as any recorded storm event data was unavailable for validation. Furthermore, a sensitivity analysis of the proposed model has been conducted.