Year
1967Duration
6 yearsCost
£1.1bn (£7.9bn today)Location
PakistanProject achievements
Economy boosted
More crops produced, energy provided.
Solved the problem
How to increase agricultural production with better water control.
Used engineering skill
Built a dam to store water and provide electricity.
Take control of Pakistan’s rivers and boost the ability to irrigate growing crops
The Mangla dam is a multipurpose dam on the river Jhelum in the Mirpur district of Pakistan.
The 7th largest in the world, the dam is named after the nearby village of Mangla. It is used for irrigation and producing hydro-electric power.
The scheme was designed by London firm Binnie and Partners, led by engineer Geoffrey Binnie, an ICE Fellow.
The structure was built to give farmers in Pakistan more water during crucial growing seasons. Before the dam's construction the country's irrigation system was dependent on the unregulated flows of the river Indus and its tributaries.
Pakistan’s agricultural output was very low often because there wasn’t enough water to irrigate fields while crops were growing. Things were often made worse by flooding during monsoon season and a lack of reservoirs to store water when rivers were high.
The Mangla project was developed after Pakistan and India signed the Indus Water Treaty in 1960. That gave Pakistan rights to the 3 western rivers of India – the Jhelum, Chenab and Indus.
Mangla was the first of 2 dams built to strengthen Pakistan’s ability to irrigate its crops. The other was the Tarbela dam on the river Indus.
Did you know …
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More than 280 villages were submerged by water when the Mangla dam was built. The towns of Mirpur and Dadyal were also flooded. Around 110,000 people had to move out of the area.
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Some of the people affected were given work permits for the UK. The government was one of the international guarantors for the project and migrant status was part of a compensation package for locals.
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Around 70% of Britain’s Pakistani community originate from the Dadyal-Mirpur area affected by the dam. According to the 2011 census there are 747,000 Mirpuris in the UK.
Difference the dam has made
The Mangla project has boosted the volume of water that can be used for irrigation from the river Jhelum and its tributaries. The dam can currently irrigate up to 1.3m acres of land.
The dam is credited with saving lives and reducing damage to property by storing and holding back storm waters – e.g during the floods that hit Pakistan in September 2014.
The scheme has produced hydro-electricity for over 50 years. Energy bosses say it’s generated up to 8% of the country’s electricity needs in some years.
How the work was done
The Mangla dam is 3,140m long and 147m high. It covers a surface area of 251km². It was designed to withstand earthquakes stronger than any experienced in the region.
Engineers working on the project used clay and sandstone bedrock excavated near the site of the dam. Gravel for the scheme was taken from the bed of the river Jhelum.
Challenges engineers faced included the discovery of shear zones – weaknesses – in the region’s clay beds during survey work for the project.
The discovery of the shear zones meant a toe weight had to be placed on the upstream side of the dam. A toe weight is a heavy structure at the base of a dam which gives it extra support.
Engineers built the scheme’s power house at the foot of the structure and constructed 5 steel tunnels to carry water to the plant. The station now has 10 electricity-generating turbines.
People who made it happen
- Designer: Geoffrey Binnie, ICE Fellow
- Contracting engineers: Mangla Dam Contractors, a consortium of 8 US companies
