2D Flood Analysis of Rel River using HEC RAS

Abstract

Floods are common in India, with 60% of flood-prone cities experiencing flash floods due to heavy rainfall or glacial outbursts. This case focuses on a flash flood in Banaskantha, triggered by heavy rainfall in the Aravalli Hills. A semiarid region, Banaskantha experienced similar events in 2015 and 2017. To assess flood hazards, the catchment area is divided into 52 micro-watersheds, allowing for 2D flood simulations using rainfall data. The HEC-RAS system analyzed Rel river’s unsteady flow, while ArcGIS identified flood-prone zones. The model's accuracy was validated by comparing it with past flood events.