FLOOD MODELING OF RIVER GODAVARI USING HEC-RAS

Abstract

Many cities and towns are developed on downstream side of dams. Some of them are established on the banks of river. During the monsoon period, when the dam is full at its Maximum Reservoir Level (MRL) and still the surplus floods are approaching into dam submergence, the maximum discharge is released from the dam to avoid the overtopping. This results into floods on downstream and may cause the disaster in cities or towns settled on banks of rivers. To facilitate the appropriate measures for effective flood mitigation in advance, there is a need to model the flood plain. With the advent of modern technology, the use of sophisticated softwares in flood modeling helps in getting an idea of extent of flood at its submergence. This paper presents a case study of Godavari river flood modeling using HEC-RAS software. The flood released for Gangapur dam, which is constructed on upstream of Nashik city at 14 km distance is considered for the modeling. The flood discharge is based on the worst discharge of 1969 flood. The river, 14 bridges across the river and the flood plain are modeled. The model facilitates to locate the flood plain and its extent for effective flood mitigation measures.