Development of emergency action plan (EAP) for Tilaiya Dam - A case study

Dams, crucial structures erected across rivers, serve various purposes for the well-being of humanity. Typically, of-substantial size, these constructions store significant water volumes. The failure of such structures is marked by the-abrupt, uncontrolled discharge of stored water, often coinciding with severe climatic events. This can result in catastrophic-consequences, causing substantial loss of lives, property, and severe environmental impacts. Consequently, it becomes-imperative for dam owners to formulate and execute an Emergency Action Plan (EAP) to mitigate the potential-repercussions of an unlikely dam failure event. This paper delves into the development of a Tier-I EAP for Tilaiya Dam, owned by the Damodar Valley Corporation (DVC) and situated in Hazaribagh and Koderma districts of Jharkhand. The process of creating the EAP for Tilaiya Dam entailed-documenting the dam's operational and safety evaluation procedures, identifying potential emergencies, and classifying their severity levels, estimating conse-quences through Dam Break Analysis for two failure scenarios (overtopping and sudden failure) and Large Controlled releases, delineating the roles and responsibilities of relevant authorities during-emergencies, and identifying available resources. Numerical simulations, utilizing the HEC-RAS computer program, were-employed to simulate dam failure floods and large controlled releases based on two-dimensional, depth-averaged flow-equations. The Damodar Valley Corporation developed Hazard classification, evacuation, and mitigation plans using information derived from inundation maps. The finalized EAP will be shared with all stakeholders for review and approval before its official endorsement.