Preparation of flood Inundation Map for Dhora dam using HEC-RAS 2D

Abstract

The Dhora Dam is an earthen dam situated in the Rudrapur block of the Udham Singh Nagar District (Uttrakhand) in the hamlet of Najimabad. Its coordinates are 28°56'18" N and 79°34'56" E. The dam is 16.15 m tall and 9050 m long, with a reservoir capacity of 44.89 million cubic meters. This dam is mostly used to irrigate the area of Uttarakhand and Uttar Pradesh. If Dhora dam fails then it causes devastating consequences at the downstream areas. Therefore, the dam breach simulation and determine the flood impacts are crucial for reducing the negative impacts of dam failure. This research conducted a dam breach analysis considering overtopping failure at full reservoir level using HEC-RAS 2D software version 6.4.1. It provides specific information regarding flood characteristic such as flow depth, velocity of flow, flow rate and water surface elevation values. The main goal is to create an inundation map for the downstream areas of dam and it is prepared using QGIS. In times of emergency, these maps can aid local government and other stakeholders save lives by providing early warning.