Explanation:

Hirakud Dam is built across the Mahanadi River, about 15 kilometres (9 mi) from Sambalpur in the state of Odisha in India. Behind the dam extends a lake, Hirakud Reservoir, 55 km (34 mi) long. It is one of the first major multipurpose river valley projects started after India's independence.Before the devastating floods of 1936, Sir M. Visveswararya proposed a detailed investigation for storage reservoirs in the Mahanadi basin to tackle the problem of floods in the Mahanadi delta. In 1945, under the chairmanship of Dr. B. R. Ambedkar, the Member of Labour, it was decided to invest in the potential benefits of regulating the Mahanadi for multi-purpose use.