Tarbela Dam

Tarbela Dam
Tarbela Dam during the 2010 floods
Official name	Tarbela Dam
Location	Tarbela, Khyber Pakhtunkhwa, Pakistan
Coordinates	34°05′23″N 72°41′54″E / 34.0897222222°N 72.6983333333°E / 34.0897222222; 72.6983333333Coordinates: 34°05′23″N 72°41′54″E / 34.0897222222°N 72.6983333333°E / 34.0897222222; 72.6983333333
Construction began	1968
Opening date	1976
Construction cost	USD 1.497 billion
Dam and spillways
Impounds	Indus River
Height	143.26 metres (470 ft) from river level
Length	2,743.2 metres (9,000 ft)
Reservoir
Creates	Tarbela reservoir
Total capacity	13.69 cubic kilometres (3.28 cu mi)
Catchment area	168,000 km2 (65,000 sq mi)
Surface area	250 km2 (97 sq mi)
Power station
Turbines	10 × 175 MW 4 × 432 MW
Installed capacity	3,478 MW 6,298 MW (max)

Tarbela Dam (Urdu/Pashto:تربیلا بند) is an earth fill dam located on the Indus River in Pakistan. It is the largest earth-filled dam in the world and fifth-largest by structural volume. It is named after the town Tarbela, in Khyber Pakhtunkhwa, about 50 kilometres (31 mi) northwest of Islamabad.

The dam is 485 feet (148 m) high above the riverbed. The dam forms the Tarbela Reservoir, with a surface area of approximately 250 square kilometres (97 sq mi). The dam was completed in 1976 and was designed to store water from the Indus River for irrigation, flood control, and the generation of hydroelectric power.

The primary use of the dam is for electricity generation, the installed capacity of the 3,478 MW Tarbela hydroelectric power stations will increase to 6,298MW after completion of the ongoing fourth extension and the planned fifth extension financed by Asian Infrastructure Investment Bank and the World Bank.

The project is located at a narrow spot in the Indus River valley, at Tarbela between Haripur District and Swabi District, approximately 60 kilometers northwest of Islamabad.

The main dam wall, built of earth and rock fill, stretches 2,743 metres (8,999 ft) from the island to river right, standing 148 metres (486 ft) high. A pair of concrete auxiliary dams spans the river from the island to river left. The dam's two spillways are located on the auxiliary dams rather than the main dam. The main spillway has a discharge capacity of 18,406 cubic metres per second (650,000 cu ft/s) and the auxiliary spillway, 24,070 cubic metres per second (850,000 cu ft/s). Annually, over 70% of water discharged at Tarbela passes over the spillways, and is not used for hydropower generation.