Construction of Mangla Dam West pakistan 1961 to 1967 Part - 1/4

Construction of Mangla Dam West pakistan 1961 to 1967 Part - 2/4

Construction of Mangla Dam West pakistan 1961 to 1967 Part - 3/4

Construction of Mangla Dam West pakistan 1961 to 1967 Part - 4/4

Power House

The Power House has been constructed at the toe of intake embankment at the ground surface elevation of 865 ft. S.P.D. The water to Power House is supplied through five steel lined tunnel of 30/26 ft. diameter. Each tunnel is designed to feed two generating units. The Present installed capacity at Power Station is 1000 Megawatts with 15% over load generating capacity at high reservoir level. The Power House tailrace discharges into New Bong Canal which has a length of 25,000 ft. with discharge capacity of about 49,000 cusecs, and terminates at an automatic gate control headworks at 7miles downstream located near old Bong Escape headworks.

Main Dam

The Main Dam is located at Mangla on the river Jhelum.

It is an earth-fill type dam with maximum height of 380 ft. above river bed with a crest length of 11,000 ft (3,353 meters).The Main Spillway is a gated concrete structure of submerged orifice type with nine radial gated 36'x40' capable of passing a peak flood of 870,000 cusecs at maximum conservation level of 1202 ft. S.P.D. The Main spillway consists of an approach channel head works, two-stage stilling basin with too chutes and pools separated by a weir and a tailrace channel leading into the river Jhelum.

MAIN IDEA OF CONSTRUCTION

Mangla Dam project was actually conceived in 1950's as a multipurpose project to be constructed at a place called Mangla across river Jhelum located 20 miles upstream of Jhelum town. The initial investigation and its feasibility studies were completed in 1958. The project was later included in the Indus Basin project which was completed during 1960-71 except Tarbela Dam Project which started partial operation in 1975-76.

History of Mangla Dam

As a consequence of the partition of the indo-Pakistan Sub-Continent , in 1947 India and Pakistan became independent sovereign states. The irrigation system which existed at that time was divided between the two countries which resulted in an international water dispute which was finally resolved by signing of the Indus Water Treaty in 1960 under the aegis of World bank. The treaty assigned to India the three eastern rivers (Ravi, Beas and Sutlej) and to Pakistan the three Western rivers (Indus, Jhelum and Chenab, and provided for construction of transfer of irrigation supplies from the western rivers to areas in Pakistan formerly served by the eastern rivers. In addition it included construction of some development works to compensate for perpetual loss of eastern river's water. The works proposed under the Treaty were two dams, five barrages, one siphon and eight inter-river link canals. Mangla Dam on Jhelum and Tarbela on Indus river were the tow dams.

Mangla Dam

The Mangla Dam is the twelfth largest dam in the world. It was constructed in 1967 across the Jhelum River, about 67 miles (100 km) south-east of the Pakistani capital,Islamabad in Mirpur District of Azad Kashmir, Pakistan. The main structures of the dam include 4 embankment dams, 2 spillways, 5 power-cum-irrigation tunnels and a 1,000 MWpower station.

The main dam is 10,300 feet (3140 m) long and 454 feet (138 m) high (above core trench) with a reservoir of 97.7 square miles (253 km²). Since its first impounding in 1967, sedimentation has occurred to the extent of 1.13 million acre feet(1.39 km³), and the present gross storage capacity has declined to 4.75 million acre feet (5.86 km³) from the actual design of 5.88 million acre feet (7.25 km³). The live capacity has declined to 4.58 million acre feet (5.65 km³) from 5.34 million acre feet (6.59 km³). This implies a reduction of 19.22% in the capacity of the dam.

The power station of Mangla dam consists of 10 units each having capacity of 100 MW.

In order to remedy the storage capacity decreases, the Pakistani government has decided to raise the dam by 40 feet (12 m), to 494 feet (151 m) high. This will increase the reservoir capacity by 18% and provide an additional 644 MWh of power, but will displace 40,000 people currently living near the reservoir.

The project was designed primarily to increase the amount of water that could be used for irrigation from the flow of the Jhelum and its tributaries. Its secondary function was to generate electrical power from the irrigation releases at the artificial head of the reservoir. The project was not designed as a flood control structure, although some benefit in this respect also arises from its use for irrigation and water supply. The Government of Pakistan had agreed to pay royalties to the Government of AJK (Azad Jammu and Kashmir) for the use of the water and electricity generated by the dam. Over 280 villages and the towns of Mirpur and Dadyal were submerged and over 110,000 people were displaced from the area as a result of the dam being built. Some of those affected by the dam were given work permits for Britain by the Government of Pakistan, and as a result, in many cities in the UK the majority of the 'Pakistani' community actually originated from the Dadyal-Mirpur area of the disputed region of Jammu & Kashmir.

Mangla Dam is approx 67 miles (100 km) south-east of the Pakistani capital, Islamabadwhile Tarbela Dam is 60 miles (100 km) northwest.