Nagarjuna Sagar DamEdit profile
Nagarjuna Sagar Dam (Telugu: నాగార్జునసాగర్ ఆనకట్ట) is the world's largest masonry dam built across Krishna River in Nagarjuna Sagar, Nalgonda District of Andhra Pradesh, India, between 1955 and 1967. The dam contains the Nagarjuna Sagar reservoir with a capacity of up to 11,472 million cubic metres. The dam is 490 ft (150 m). tall and 16 km long with 26 gates which are 42 ft (13 m). wide and 45 ft (14 m). tall.
Nagarjuna Sagar was the earliest in the series of large infrastructure projects initiated for the Green Revolution in India; it also is one of the earliest multi-purpose irrigation and hydro-electric projects in India. The dam provides irrigation water to the Nalgonda District, Prakasam District, Khammam District and Guntur District and electric power to the national grid.History
The proposal to construct a dam to use the excess waters of the Krishna river was put forward by the British rulers in 1903. Since then, various competing sites in Siddeswaram, Hyderabad and Pulichintala were identified as the most suitable locations for the reservoirs. The perseverance of the Raja of Muktyala paved way for the site identification, design and construction of the dam. Nagarjunasagar was the earliest in the series of "modern temples" taken up to usher in the Green Revolution in India.
Project construction was officially inaugurated by Prime Minister Jawaharlal Nehru, on 10 December 1955, and proceeded for the next twelve years. The reservoir water was released into the left and right bank canals by the then Prime Minister, Indira Gandhi in 1967. Construction of the hydropower plant followed, with generation increasing between 1978 and 1985, as additional units came into service.
The construction of the dam submerged an ancient Buddhist settlement, Nagarjunakonda, which was the capital of the Ikshvaku dynasty in the 1st and 2nd centuries, the successors of the Satavahanas in the Eastern Deccan. Excavations here had yielded 30 Buddhist monasteries, as well as art works and inscriptions of great historical importance. In advance of the reservoir's flooding, monuments were dug up and relocated. Some were moved to Nagarjuna's Hill, now an island in the middle of the reservoir. Others were moved to the mainland.Effect of the project
The project benefited farmers in the districts of Guntur, Prakasam, Krishna, Nalgonda and Khammam. The right canal (a.k.a Jawahar canal) is 203 km long and irrigates 1.113 million acres (4,500 km²) of land. The left canal (a.k.a Lalbahadur Shastri canal) is 295 km long and irrigates 0.32 million acres (800 km²) of land in Nalgonda and Khammam districts of Telangana region. The project transformed the economy of above districts. 52 villages were submersed in water and 24000 people were affected. The relocation of the people was completed by 2007.Power Generation
The hydroelectric plant has a power generation capacity of 815.6 MW with 8 units (1x110 MW+7x100.8 MW). First unit was commissioned on 7 March 1978 and 8th unit on 24 December 1985. The right canal plant has a power generation capacity of 90 MW with 3 units of 30 MW each. The left canal plant has a power generation capacity of 60 MW with 2 units of 30 MW each.
The dam is constructed on the border of Guntur and Nalgonda districts. The dam also provides drinking water to the Nalgonda town.Statistics
- Catchment Area : 215000 km² (83012 sq mi)
- Masonry dam
- Spillway of dam : 471 m
- Non-over flow dam : 979 m
- Length of Masonry dam : 1450 m
- Maximum height : 125 m
- Earth dam
- Total Length of Earth dam : 3414 m
- Maximum height : 28 m