The Hirakud Dam in Orissa stands in the Sambalpur district across the Mahanadi River. The dam was built in the year 1957 and is the largest earthen dam that exists. It is also a major multipurpose river valley project in India that was built after India was liberated from the British Rule in the year 1947. The Hirakud is 6 Kilometers from NH (National Highway) and 8 kilometers from the Hirakud railway station. It is 61 meters in height and 4801 meters in length stretching between the hills of Lamdungri in the left and the Chandili Dunguri on the right. The dam has 21 kilometers of dykes. The Hirakud is not only the longest earthen dam but also the biggest artificial lake in Asia which has a storage capacity of 743 square kilometers and a shoreline of over 640 kilometers.

The construction of the dam dates back to the period of devastating floods in the year 1937. The foundation of the dam was laid by Sir Howthrone Lewis, the then governor of Orissa on 15th of March 1946 and it was officially inaugurated by Jawaharlal Nehru in the year 1957. The project had started functioning at its full capacity from the year 1966.

The Hirakud Dam regulates the flow of the Mahanadi River and as a result alleviates the situations of floods at various regions. Not only does it control floods but also it relieves the situations of drought. Another important function of the dam is to produce hydro electricity with the help of several hydro-electric power plants.The entire project consists of three dams namely the Hirakud dam, the Tikarpara dam and the Naraj dam. It provides 1, 55,635 Hectares and 1, 08,385 Hectares of irrigation to Rabi and Kharif crops respectively in the districts of Sambalpur, Bargarh, Bolangir, and Subarnpur in Orissa. The water released through the power house irrigates a further 436000 Hectares in the Mahanadi delta. The two powerhouses at Burla and Chiplima have a cumulative installed capacity of 307.5 MW. The main aim of the Hirakud dam project is to control the flow of the Mahanadi River, which, with a catchment area of 132000 square kilometers, has alarming floods from time to time. Hirakud dam intercepts 83400 square kilometres(32200 square miles) of Mahanadi catchments.

The project provides flood protection to 9500 square Kilometers of delta area in the districts of Cuttack and Puri. The entire irrigated patch of land of the dam constitutes two canal systems. They are the Sason canal and the Bargarh canal. Each canal is of different type: the Sason canal is of the ridge type and the Bargarh canal is of the contour type. The Chief Engineer, two Superintending Engineers and seven Executive Engineers and their staff are concerned with the maintenance and repair of the dam with the funds allotted to the Chief Engineer by the State government from time to time. The difference between the ridge type canal and the contour type canal is that the ridge type canal does not have banks on either side unlike the contour type canal.

A very important benefit of the Hirakud Dam is that it has facilitated the exploitation the rich resources of Orissa like iron, coal, manganese, bauxite, chromite and limestone. At present, the Hirakud project has facilitated power supply to an aluminium plant at Hirakud paper mills at Brijrajnagar, cement works at Rajgangpur, iron and steel plant at Rourkella and several other industries in Cuttack, Puri, Sambalpur, Keonjhar, Mayurbhanj, Bolangir and other districts. In the recent years pisiculture has been a growing activity in the areas around the Hirakud Project.

Cattle Island which stands at one extreme of the Hirakud Project has become an area of tourist attraction. It is a natural wonder where presently only the cattle dwell. The island is nothing but a submerged hill. After the construction of the dam the hill was covered with waters from the reservoir and henceforth has become an island.

Hence it can be concluded that the Hirakud Dam is an asset for the state of Orissa because it is this dam that regulates the flow of water from the Mahanadi River by curtailing it during the monsoons and increasing it during the dry season.