Bakhtiari Dam

Preliminary studies for the dam began in 1996 and were carried out by Mahab Qods Consulting Engineers. The studies were carried out over a period of 33 months and in March 2000, the results were given to Iran Water & Power Resources Development Co (IWPCO). In May 2005, IWPCO awarded consultation services for the project to Moshanir Consulting Engineers, Dezab Consulting Engineers, Econo-Electrowatt/Boyri and Stucky Pars Consulting Engineers.[2] On April 30, 2007 the construction contract was awarded to China's Sinohydro Corporation.[3] The contract is worth $2 billion and was to be funded with direct investment from China.[4][5] Sinohydro signed the 118-month contract on March 15, 2011 and was expected to be working with Iran's Farab.[6] But the Iranian government rejected Sinohydro's bid in late May 2012 and handed the project over to Khatam-al-Anbiya (KAA), which is controlled by the Iranian Revolutionary Guard Corps.[7] The KAA commander announced on 19 December 2012 that construction of the dam had begun with access roads leading to the project site.[8] On 25 March 2013, Iranian President Mahmood Ahmadinejad attended a groundbreaking ceremony for the dam, initiating its construction.[9]

During construction, a total of six bridges will be built to support workers, vehicles and equipment in addition to various access roads. To divert the river, two tunnels, 1,151 m (3,776 ft) and 1,180 m (3,871 ft) in length will be constructed at the dam's left abutment. They will have discharge capacities of 2,090 m³/s (73,808 cu ft/s) and 1,680 m³/s (59,329 cu ft/s) respectively. To divert the water, two roller-compacted concrete cofferdams will be constructed. The upstream cofferdam will be 51 m (167 ft) high and the downstream 25 m (82 ft). Material to construct the dam including aggregate will come from the actual excavation of the dam site along with three quarries in the area.[10]

The Bakhtiari will be a 325 m (1,066 ft) tall and 434 m (1,424 ft) long variable-radius arch dam. It will be 10 m (33 ft) wide at its crest and 30 m (98 ft) wide at its base while being composed of 3,100,000 m³ (109,475,467 cu ft) of concrete. The dam's reservoir will have a normal capacity of 4,845,000,000 m³ (3,927,905 acre⋅ft) and an active or "useful" capacity of 3,070,000,000 m³ (2,488,890 acre⋅ft). At a normal elevation of 830 m (2,723 ft) above sea level, the reservoir will have a surface area of 58.7 km² (23 sq mi), maximum width of 1 km (1 mi) and length of 59 km (37 mi). Its catchment area will be 6,288 km² (2,428 sq mi).[10]

The dam will contain two spillways. The main service spillway will be an 11 m (36 ft) diameter tunnel in the right abutment with two flood gates. The discharge capacity of this spillway will be 5,830 m³/s (205,885 cu ft/s). The second spillway will be two radial gates on the dam's orifice with a discharge capacity of 1,510 m³/s (53,325 cu ft/s). The dam's powerhouse will be located underground at the left abutment. It will be 161 m (528 ft) long, 64 m (210 ft) high and 24 m (79 ft) wide; containing 6 x 250 MW vertical Francis turbine-generators. Before reaching the power station, water will be transferred by six 51 m (167 ft) long penstocks. Feeding water to the penstocks is a 504 m (1,654 ft) long headrace tunnel with a three gate intake structure.[10]

• List of power stations in Iran
• International rankings of Iran
• Dams in Iran