Gal Oya Dam

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Gal Oya Dam
Gal Oya Dam.JPG
Gal Oya dam in Senanayake Samudhraya
Sri Lanka rel-2 location map.svg
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Location of Gal Oya Dam in Sri Lanka
Country Sri Lanka
Location Gal Oya National Park
Coordinates 07°12′37″N81°32′10″E / 7.21028°N 81.53611°E / 7.21028; 81.53611 Coordinates: 07°12′37″N81°32′10″E / 7.21028°N 81.53611°E / 7.21028; 81.53611
Purpose Irrigation, Power
Construction beganAugust 24, 1949 (1949-08-24)
Opening date1953
Owner(s) MIWRM
Dam and spillways
Type of dam Embankment dam
Impounds Gal Oya
Height (thalweg)140 ft (43 m)
Length3,600 ft (1,100 m)
Dam volume2,000,000  cu yd (1,500,000  m3)
CreatesSenanayake Samudhraya
Total capacity770,000  acre⋅ft (950,000,000  m3)
Surface area35 sq mi (91 km2)
Inginiyagala Power Station
Coordinates 07°12′51″N81°32′14″E / 7.21417°N 81.53722°E / 7.21417; 81.53722
Operator(s) Ceylon Electricity Board
Commission dateJune 1963 (1963-06)
Type Conventional
Installed capacity 11 MW

The Gal Oya Dam (also known as Inginiyagala Dam) is an embankment dam in the Uva Province of Sri Lanka. The dam creates one of the largest reservoirs in the country, the Gal Oya Reservoir. Water from the reservoir is used primarily for irrigation in the Uva and Eastern provinces, in addition to powering a small hydroelectric power station. Construction of the dam and reservoir began in August 24, 1949, completing four years later in 1953. [1]


Dam and reservoir

The dam is constructed between two hills at the small town of Inginiyagala, measuring 3,600 ft (1,100 m) and 140 ft (43 m) in length and height respectively, consisting of 2,000,000  cu yd (1,500,000  m3 ) of soil. The dam, built by Morrison-Knudsen company, creates the Gal Oya Reservoir. [1]

The reservoir, also known as the Inginiyagala Reservoir, and more commonly as the Senanayake Samudraya (after D.S. Senanayake), has a total storage of 770,000  acre⋅ft (950,000,000  m3 ) and a surface area of 35 sq mi (91 km2). [1] [2]

Power station

In addition to downstream irrigation, water from the reservoir is used to power the Inginiyagala Power Station, a hydroelectric power station located immediately downstream of the dam. The power station consists of four units of (2.475MWx2 & 3.15MWx2)11.25 MW , commissioned in 1952 unit 1,2 & 1962 unit 3,4. [1] [3]

See also

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  1. 1 2 3 4 "Senanayake Samudhraya". Ministry of Irrigation and Water Resources Management. Archived from the original on 4 March 2016. Retrieved 14 February 2014.
  2. Liyana Arachchi (19 August 2013). "Strength of Senanayake Samudraya dam". Daily News . Archived from the original on 22 February 2014. Retrieved 14 February 2014.
  3. "CEB Generation Network". Ceylon Electricity Board. Archived from the original on 16 January 2014. Retrieved 14 February 2014.