The Tehri Dam is the highest dam in India, 2nd highest in Asia and 8th highest in world. It is a multi-purpose rock and earth-fill embankment dam on the Bhagirathi River near Tehri in Uttarakhand, India. It is the primary dam of the THDC India Ltd. and the Tehri hydroelectric complex. Phase 1 was completed in 2006, the Tehri Dam withholds a reservoir for irrigation, municipal water supply and the generation of 1,000 MW of hydroelectricity. One more project of the installed capacity of 1,000 MW pumped storage hydroelectricity are under construction. |
A preliminary investigation for the Tehri Dam Project was completed in 1961 and its design was completed in 1972 with a 600 MW capacity power plant based on the study. Construction began in 1978 after feasibility studies but was delayed due to financial, environmental and social impacts. In 1986, technical and financial assistance was provided by the USSR but this was interrupted years later with political instability. India was forced to take control of the project and at first it was placed under the direction of the Irrigation Department of Uttar Pradesh. However, in 1988 the Tehri Hydro Development Corporation was formed to manage the dam and 75% of the funding would be provide by the federal government, 25% by the state. Uttar Pradesh would finance the entire irrigation portion of the project. In 1990, the project was reconsidered and the design changed to its current multi-purpose. Construction of the Tehri Dam was complete in 2006 while the second part of the project, the Koteshwar Dam, is nearly complete with two out of four generators operational. The other two are expected to be commissioned in March 2012 while the pumped storage power planned is slated for commissioning in February 2016. Technical description
The dam is a 260.5 metres (855 ft) high rock and earth-fill embankment dam. Its length is 575 metres (1,886 ft), crest width 20 metres (66 ft), and base width 1,128 metres (3,701 ft). The dam creates a reservoir of 2.6 cubic kilometres (2,100,000 acre·ft) with a surface area of 52 square kilometres (20 sq mi). The installed hydrocapacity is 1,000 MW along with an additional 1,000 MW of pumped storage hydroelectricity. The Tehri Dam and the Tehri Pumped Storage Hydroelectric Power Plant are part of the Tehri Hydropower Complex which also includes the 400 MW Koteshwar Dam downstream. The complex will afford irrigation to an area of 270,000 hectares (670,000 acres), irrigation stabilization to an area of 600,000 hectares (1,500,000 acres), and a supply of 270 million imperial gallons (1.2×106 m3) of drinking water per day to the industrialized areas of Delhi, Uttar Pradesh and Uttarakhand. Environmental issues
The Tehri Dam has been the object of protests by environmental organizations and local people of the region. In addition to the human rights concerns, the project has spurred concerns about the environmental consequences of locating a large dam in the fragile ecosystem of the Himalayan foothills. There are further concerns regarding the dam's geological stability. The Tehri dam is located in the Central Himalayan Seismic Gap, a major geologic fault zone. This region was the site of a 6.8 magnitude earthquake in October 1991, with an epicenter 500 kilometres (310 mi) from the location of the dam. Dam proponents claim that the complex is designed to withstand an earthquake of 8.4 magnitude, but some seismologists say that earthquakes with a magnitude of 8.5 or more could occur in this region. Were such a catastrophe to occur, the potentially resulting dam-break would submerge numerous towns downstream, whose populations total near half a million.
The protest message against Tehri dam, which was steered by Sundarlal Bahuguna for years. It says "We don't want the dam. The dam is the mountain's destruction." The relocation of more than 100,000 people from the area has led to protracted legal battles over...