Mahanadi

River rising in Raipur district of Chhattisgarh state, central India; length 880 km/546 mi. It flows northeast to the Hirakud reservoir, then southeast through Orissa state to the Bay of Bengal. The Hirakud Dam, over 60 m/200 ft high and 3,500 m/11,400 ft long, was built in 1957 partly to combat catastrophic flooding of the delta region.

The dam has a 270,000 kW hydroelectric power station, and water from the reservoir is used to irrigate 900,000 ha/2.2 million acres of land, mainly in the delta area.