Diamer Bhasha is a multi-purpose mega-dam project planned to be developed on the Indus River near Chilas, in the Khyber Pakhtunkhwa and Gilgit-Baltistan regions of Pakistan.
It is the biggest ever dam project undertaken in Pakistan. Standing 272m-tall, Diamer Bhasha is also expected to be one of the tallest dams in the world.
Pakistan’s Water and Power Development Authority (WAPDA) proposes to develop the dam with an investment of £10.6bn ($14bn). The project will have a power generating capacity of 4.5GW, apart from providing water storage and flood mitigation facilities for Pakistan.
Construction on the project is expected to be started in 2020 with completion expected in 2029.
Diamer Bhasha Dam location and site details
The Diamer Bhasha Dam, with a huge reservoir, will be located on the Indus River, in the Diamer district of Pakistan’s Gilgit-Baltistan province, approximately 315km upstream of the Tarbela Dam and 40km downstream of the Chilas town.
The two powerhouses of the project are proposed to be developed in Kohistan, in the neighbouring Khyber Pakhtunkhwa (KP) province.
The project area will encompass approximately 110km², extending 100km from the dam site up to the Raikot Bridge on the Karakoram Highway.
A total of 32,139 acres of land including 31,977 acres in Gilgit-Baltistan and 162 acres in Khyber Pakhtunkhwa was acquired as of January 2019, which comprises approximately 86% of the total land required for the project.
Controversy over Diamer Bhasha Dam
The Diamer Bhasha Dam project has drawn controversy because of its location in Gilgit Baltistan, a disputed territory between India and Pakistan. India calls Gilgit Baltistan as the Pakistan-occupied Kashmir (PoK) and alleges that Pakistan is illegally holding this territory that originally belonged to its northernmost state Jammu and Kashmir.
India has voiced concern with Pakistan as well as with China, US and global financial institutions requesting not to fund any infrastructure project in the PoK.
Situated near the Himalayan peak Nanga Parbat, the dam project is also alleged to be in a high seismic zone. It is apprehended to have ecological fallout such as landslides and floods that might affect the adjacent areas in Pakistan as well as in India.
Bilateral territorial dispute and the seismicity of the project area have refrained the World Bank, the Asian Development Bank (ADB), as well as other international donor agencies from providing financial assistance to the controversial project.
The Diamer Bhasha project has also triggered significant local resistance, as it is estimated to displace more than 4,200 families in nearby areas and submerge a huge part of the Karakoram Highway to China.
Moreover, since part of the project area lies in Khyber Pakhtunkhwa (KP), it has led to a domestic dispute between two Pakistani provinces Gilgit Baltistan and KP with both the provinces contesting for claims over the royalty from the dam. The boundary issues between the two provinces remain unsettled.
Diamer Bhasha Dam project development details
The dam project was conceived as part of the Water Vision 2025 presented by WAPDA in July 2001.
Diamer Bhasha was the first and the biggest among the five multi-purpose dam projects to be undertaken as part of the North Indus River Cascade scheme announced by the Pakistani Government in January 2006.
The Diamer Bhasha project, however, remained in limbo for a long time due to the non-availability of funds.
The initiative received fresh impetus with the inauguration of China’s Belt and Road Initiative (BRI) in 2017, as China expressed its willingness to support the North Indus River Cascade projects under the Pakistan Economic Corridor (CPEC), a flagship framework under the BRI.
Pakistan, however, withdrew the Diamer Bhasha Dam from the CPEC projects list in 2018, due to China’s strict monetary conditions as well as its ambition to hold ownership of the mega project. Nevertheless, Pakistan is determined to proceed with the dam project.
The Chief Justice of Pakistan initiated a crowd-funding campaign for the Diamer Bhasha Dam Project in October 2018.
In August 2019, WAPDA received bids from two joint ventures, each comprising a Chinese and a local company, for constructing the dam. One joint venture includes China Gezhouba Group Company and Pakistan’s Ghulam Rasool & Company (GRC), while the other joint venture is between Power Construction Corporation of China and Pakistan’s Frontier Works Organization (FWO).
The dam construction contract is expected to be awarded in the first half of 2020.
Diamer Bhasha dam and reservoir details
Diamer Bhasha will be a roller compacted concrete (RCC) gravity dam with a crest length exceeding 1km and a maximum height of 272m.
The reservoir created by the dam will impound up to 7,500,000 acre-feet of water accounting for approximately 15% of the annual river flow. The gross storage capacity of the reservoir will be ten billion cubic metres (bcm), of which 7.9bcm will be the live storage capacity.
Spillways of the dam will comprise of 14 radial gates, each measuring 16.25m-high and 11.5m-wide. The maximum water discharge capacity of each gate will be 18,128m³/s.
Diamer Bhasha power plant make-up
The Diamer Bhasha hydroelectric facility will consist of two underground powerhouses on either bank of the Indus River, with an installed capacity of 2,250MW each.
Each powerhouse will be equipped with six turbo-generator units of 375MW capacity each. The power intake structure for each powerhouse will include two surge tanks and two 15.3m-diameter headrace tunnels connected to three penstocks each.
Each underground powerhouse will have separate transformer and switchgear caverns.
Water from each powerhouse will be discharged back to the river through two 18.8m-diametre tailrace tunnels.
The Executive Committee of the National Economic Council (ECNEC) of the Government of Pakistan, approved £2.34bn (PKR474bn) for the preliminary dam construction phase of the Diamer Bhasha project in April 2018. A revised initial cost of PKR479.68bn (£2.37bn) was approved in November 2018.
The US Agency for International Development (USAID) approved £15.31m ($20m) for conducting a feasibility study for the project in 2013.
The USAID contracted Mott MacDonald to review the dam design in June 2015. Malcolm Dunstan & Associates (MD&A) served as the RCC specialist for Mott MacDonald.
MWH Global, in consortium with National Engineering Services Pakistan (NESPAK) and Associated Consulting Engineers (ACE), completed environmental and social impact assessment (ESIA) for the project in August 2016, under a $17.9m contract awarded by the USAID.