The idea for a dam on the Beas at the Pong site was first proposed in 1926 and subsequent surveys of the Indus River and its tributaries were ordered by the Punjab Government in 1927. Interest in the dam declined after the report deemed the project difficult because of flood waters. In 1955, geological and hydrological studies were carried out on the Pong site and an embankment design was recommended. In 1959, extensive studies were carried out and recommended an embankment dam with a gravity section. A final design was issued and construction began in 1961 on the dam which was called Beas Project Unit II - Beas Dam. The Pandoh Dam upstream being the Beas Project Unit I. It was completed in 1974 and the power station was later commissioned between 1978 and 1983. About 150,000 people were displaced by the dam's large reservoir under a poorly planned and executed relocation program.
Design
The Pong Dam is a tall and long earth-fill embankment dam with a gravel shell. It is wide at its crest and wide at its base. The total volume of the dam is and its crest sits at an elevation of above sea level. The dam's spillway is located on its southern bank and is a chute-type controlled by six radial gates. Its maximum discharge capacity is. The reservoir created by the dam, Maharana Pratap Sagar, has a gross capacity of of which is active capacity. The reservoir has a normal elevation of and catchment area of. The reservoir reaches from the dam to upstream in length and covers a surface of. Located at the base of the dam is its power house. It is supplied with water via three penstocks which each meet a 66 MW Francis turbine-generator located inside the Bhatoli phakorian. The dam's elevation to the power house provides a maximum of in hydraulic head.
Displacement of people
The large reservoir created by this dam resulted in a major displacement of people from the state of Himachal Pradesh. A total of 90,702 people were displaced and 339 villages affected. The displaced people were to be resettled in Rajasthan. However, as of February 2014, 9732 requests for land allotment were still pending. Himachal Pradesh threatened Rajasthan that they will file a contempt of court in Supreme Court if land is not allotted.
