HARIPUR: The year 2024 shows a significant milestone for the development of water and hydropower resources in Pakistan as the Tarbela Dam turns 50 this year.

After the completion of civil work by Wapda in the third quarter of 1974, the filling of the Tarbela Dam’s reservoir began 50 years ago, the project’s media wing said in a statement.

It declared Tarbela Dam a symbol of national pride in the last five decades and said the reservoir was the capstone of the Indus Basin Plan to ensure the continued and improved supply of water to millions of acres of irrigated land in Pakistan, mitigate floods and generate green, clean and most affordable hydro-electricity to move the wheel of the economy.

“Tarbela Dam Project has played an instrumental role for economic development and social uplift in Pakistan during the last 50 years. The contribution of Tarbela Dam Project has made towards progress in the country can be judged from the fact thatit has released 406 million acre feet (MAF) of stored water from the reservoir for agriculture and contributed 590,361 million units of low-cost and environment friendly hydel electricity to the national grid.”

$406bn benefits drawn from project in 50 years, says its media wing

According to the media wing, the economic and financial benefits of one MAF of water are estimated at $1 billion, so the benefits from Tarbela Dam in the last 50 years total $406 billion.

Tarbela Dam, the largest earth and rock-fill dam in the world at the time of its completion, is located across the River Indus 64km northwest of Islamabad. Work on the dam commenced in 1968, while all civil works were completed in 1974. The development of powerhouses commenced in phases starting from 1974.

The project consists of a 9,000 feet long and 470 feet high embankment across the entire width of the river. It has two spillways with a cumulative discharge capacity of 1,500,000 cusecs. Two auxiliary embankment dams close the low level ridges in the left bank valley. A group of four tunnels, each 0.8km long through the right abutment, were constructed for irrigation releases and power generation.

Initially, the reservoir, spread over 259 square kilometres, had a live storage of 9.68MAF. However, it later reduced to 5.77MAF due to sedimentation.

The dam’s media wing said a power station on the right bank near the toe of the main dam housed 17 power units at tunnels 1, 2, 3 and 4.

It added that Tarbela was the biggest electricity generation facility in Pakistan with installed capacity of 4888MW – 51.6 per cent of Wapda’s total hydel capacity.

The wing said the cost of the Tarbela Dam Project, including power units 1-14, totalled $2,630 million.

It added that the Tarbela 4th Extension Hydropower Project, with power units 15-17, cost $1,075 million and the under-construction Tarbela 5th Extension, with power units 18-20, $807 million.

Published in Dawn, September 13th, 2024