
Tarbela Dam
Earth and Rock-fill dam · Khyber Pakhtunkhwa, Pakistan
Tarbela Dam is an earth and rock-fill dam on the Indus in Khyber Pakhtunkhwa, Pakistan, standing 143 m (469 ft) high and completed in 1976. It carries an installed hydroelectric capacity of 4,888 MW. The structure impounds Tarbela Lake.
Tarbela Dam (Pashto: د توربېلې بند, Hindko: تربیلا بند) is an earth-filled dam on the Indus River in Pakistan's Khyber Pakhtunkhwa province. It is mainly located in Swabi Tehsil. The dam lies in the vicinity of the town of Topi, 105 km (65 mi) northwest of Islamabad and 125 km (80 mi) east of Peshawar. It is the largest earth-filled dam in the world. The dam is 143 metres (470 ft) high above the riverbed, and its reservoir, Tarbela Lake, has a surface area of approximately 250 square kilometres (97 sq mi).
The Tarbela Dam is located where the Indus River emerges from the foothills of the Himalayas and enters the Pothohar Plateau. The dam has a reservoir that stores water for irrigation, flood control, and hydroelectric power generation, capturing monsoon flows and releasing water during the low-flow winter period. The average annual flow available is 101 billion cubic meters (3221 m3/sec). It has a storage capacity of 11.9 billion cubic meters. The dam was completed in 1976.
Adapted from Wikipedia: Tarbela Dam (CC BY-SA 4.0).
- Dam type
- Earth and Rock-fill
- Structural height
- 143 m (469 ft)
- Installed capacity
- 4,888 MW
- Impounded river
- Indus
- Reservoir
- Tarbela Lake
- Location
- Khyber Pakhtunkhwa, Pakistan
- Year completed
- 1976
- Height rank
- #35 of 115 indexed
- Output rank
- #16 of 102 indexed
- Coordinates
- 34.0886°, 72.6975°
Notable: Largest earth and rock-fill dam in the world by structural volume.
Among the 115 dams indexed in YearMaps, Tarbela Dam ranks #35 by structural height, behind Jinping-I Dam (305 m). By installed generating capacity it ranks #16, behind Three Gorges Dam (22,500 MW).
Nearest cities: Abbottabad (47 km), Mansehra (54 km), Islamabad (61 km).
More about Tarbela Dam
Background
Tarbela Dam was constructed as part of the Indus Basin Project after signing of the 1960 Indus Waters Treaty between India and Pakistan. The purpose was to compensate for the loss of water supplies of the eastern rivers (Ravi, Sutlej and Beas) that were designated for exclusive use by India per terms of the treaty. By the mid-1970s, power generation capacity was added in three subsequent hydro-electrical project extensions which were completed in 1992, installing a total of 3,478 MW generating capacity.
Construction
Construction of Tarbela Dam was carried out in three stages to meet the diversion requirements of the river. Construction was undertaken by the Italian firm Salini Impregilo.
In the first stage, the Indus River was allowed to flow in its natural channel, while construction works commenced on the right bank where a 1,500 feet (460 meters) long and 694.8 feet (211.8 meters) wide diversion channel was being excavated along with a 105 feet (32 meters) high buttress dam that was also being constructed. Stage 1 construction lasted approximately 2½ years.
The main embankment dam and the upstream blanket were constructed across the main valley of the river Indus as part of the second stage of construction.
Project description
The dam is at a narrow spot in the Indus River valley, named after the village of Tarbela in the Swabi Districtwithin the Khyber Pakhtunkhwa province of Pakistan.
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 near the auxiliary dams rather than the main dam. The main service 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 without being used for hydropower generation.
Sections adapted from Wikipedia: Tarbela Dam (CC BY-SA 4.0).
Tarbela Dam: Key Facts
| Crest length | 2,743 m |
|---|
Facts from Wikidata Q1551258 (CC0).
