Mangla dam is the first-ever mega multipurpose project in Pakistan comprising of water storage & four power generating units of 100 MW each completed in 1967. Like Tarbela dam, Mangla dam is also brain-child of replacement works of Indus Water Basin Treaty signed on 19th September 1960 at Karachi by Indian Prime minister Pandat Johar Lal Nehru and President of Pakistan Field Marshal Muhammad Ayub Khan. Subsequent to completion of its up-raising project, Mangla dam has become the biggest water reservoir of Pakistan, surpassing Tarbela which has a live storage capacity of 6.45 MAF.
|Location:||Mangla, Azad Jammu & Kashmir|
|Located:||Jhelum River in the Mirpur District of Jammu & Kashmir, Pakistan|
|Local Language Name:||منگلا بند|
|Coordinates :||33.142083°N 73.645015°E|
|Construction began :||1961|
|Opening date :||1967|
|Type of dam :||Embankment dam|
|Impounds :||Jhelum River|
|Height :||147 m (482 ft)|
|Length :||3,140 m (10,302 ft)|
|Creates :||Mangla Lake|
|Total capacity :||9.12 km3 (7,390,000 acre·ft)|
|Surface area :||97 sq mi (251 km2)|
|Turbines :||10 x 100 MW|
|Installed capacity :||1,150 MW (15% overload) , 1,500 MW (max. planned)|
|Constructed Cost:||Rs. 15.587 billion (US$1.473 billion)|
|Funding By:||Funding being provided by the World Bank and the Asian Development Bank|
|Constructed Duration:||Between 1961 and 1967|
|Components include :||Main embankment, intake embankment, main spillway, emergency spillway, intake structures, 5 tunnels|
|Cubic Yards:||Total of 120 x 106|
|Award of Contract:||January 20, 1962|
|First Impounding:||February 21, 1967|
History of Mangla Dam
As a consequence of partition of the Indo-Pakistan Sub-Continent in 1947, India and Pakistan became two independent sovereign states. The Irrigation System which existed at the time of partition in 1947 was divided between the two countries without any regards to the irrigation boundaries resulting in an international water dispute which was resolved by signing of the Indus Water Treaty in 1960 under the aegis of World Bank. The Treaty assigned three Eastern rivers (Ravi, Beas and Sutlej) to India and three Western rivers (Indus, Jhelum & Chenab) to Pakistan. IBIS ManglaIt also provided construction of replacement works called Indus Basin Project (IBP) to compensate for perpetual loss of Eastern river’s water. The works proposed under the Treaty included two multipurpose dams from one of which is Mangla Dam on Jhelum river having the provision of Power Generation.
Construction work on Mangla dam commenced on March 1963 and was completed in just 4 years and three months in June 1967 at the cost of $ 434.505 million with water storage capacity of 5.88 MAF and power generation capacity of 400 MW with units 1-2-3 & 4 each of 100 MW. Its generation capacity was enhanced in 1974 by commissioning two more units i.e. 4 and 5 each of 100 MW. In 1981, the power generation capacity was further augmented by installing units 7 and 8 each of 100 MW. In view of the daily surging demand of electricity, units 9 and 10 were erected in the year 1993-1994 each of 100 MW. The cumulative production from all the ten operating units is 1000 MW.
With the passage of time the storage capacity came down to 4.67 MAF due to the natural phenomenon of silting/sedimentation. To increase its live storage capacity and maximize the hydropower potential of river Jhelum, Mangla dam up-raising project was initiated in July 2004 at a cost of Rs. 96.853 billion. The project was completed in December 2009 with the raised height of dam equal to 30 feet a d maximum permissible water level of 1242 feet (above mean sea level). Storage capacity of the raised Mangla dam is 7.48 MAF. Net increase in storage capacity is 7.48 – 4.67 = 2.81 MAF (i.e. one foot of water standing over 2.81 million acres of land). Whereas the additional 2.81 MAF of water will irrigate 1.31 million acres of land and generate 644 million more energy units per year, the raised Mangla dam has played a significant role in mitigating the flood miseries by holding in its reservoir a huge quantum of water. Had the Mangla dam not been raised to the height of 30 feet, the devastation in terms of loss of human life and livestock and damages to corps and property would have been more than what was experienced during the raging floods of September 2014.
Generally the hydroelectric generators have a useful life of 35 years but generators at Mangla are almost 50 years old and still operating efficiently and effectively. Keeping in view the growing age of the hydropower generating equipment, a plan has been devised to systematically refurbish the generators in next five years. As such the Mangla refurbishment project is in place to increase the generation capacity of Mangla hydel power station to 1310 MW from existing 1000 MW. The project, which is being implemented by WAPDA, is to be completed phase-wise on a fast-track basis. Power generation units will be refurbished by closing one tunnel (two generating units at a time). Units 5 and 6 will be refurbished by the year 2018 and Units 1 to 4 by the year 2020. Mangla refurbishment project shall stand completed by the year 2022 when all the ten units are refurbished. The latest technology will be used to optimize the generation capacity of Mangla hydel power station. With the use of this technology, the volumetric flow rate of water for generating 1310 MW of electricity shall be the same as required for generating 1000 MW of electricity.
In addition to planting 1.325 million saplings spread over and area of 1960 acres, WAPDA is also aimed at constructing soil conservation structures equivalent to 3.774 million cubic feet and 183 engineering structures during the current fiscal year 2015-2016 under the programme of watershed management. All these well-planned and concerted efforts shall go a long way towards managing the sediments and hence the enhancement of reservoir’s life by another 100 years from 100 to 110 years as earlier envisaged by the consultants in the design of Mangla dam project.
Mangla Dam was constructed between 1961 and 1967 across the Jhelum River, about 67 miles (108 km) south-east of the Pakistani capital,in Mirpur District of Azad Jammu & Kashmir. The Mangla Dam components include a reservoir, main embankment, intake embankment, main spillway, emergency spillway, intake structures, 5 tunnels.There was a total of 120 x 106 cubic yards (cu yds) of excavation for the reservoir whereas the total fill amounted to 142 x 106 cu yds and concrete to 1.96 x 106 cu yds respectively. The main embankment is earthfill with clay as the core material. Gravel and A-type sandstone are applied on the shoulders. The maximum height of embankment above the core trench is 454 feet and the length is 8,400 feet. The intake embankment is earthfill type with B-type sandstone as the core material. Gravel is applied on the shoulders. The maximum height of intake embankment above the core trench is 262 feet and the length is 1,900 feet. Sukian Dam is earthfill with B-type sandstone as the core material. A-type sandstone is applied on the shoulders. The maximum height of the intake embankment above the core trench is 144 feet and the length is 16,900 feet.