Hirakud Reservoir is one of the largest man-made reservoirs in India, built across the Mahanadi River by a combination of earth and modern dams of a total length of almost 26 kilometres. The reservoir helps regulate the water level of the river and moderates the impact of floods in the Mahanadi Delta. It provides habitat for over 130 bird species and about 54 fish, with one classified as endangered and six others as near-threatened. 21 fish species are economically important to the region as they provide a total yield of 480 tonnes per year, supporting the livelihoods of over 7,000 fishermen. The reservoir also produces around 350 megawatts of hydropower and irrigates 436,000 hectares of land. The rich biodiversity and other recreational activities in and around the reservoir make it a popular tourist destination, with over 30,000 tourists visiting annually.