|• elevation||1,524 m (5,000 ft)|
|Length||108 km (67 mi)|
The Gal Oya is a 108 km (67 mi) long river, in South east Sri Lanka. It is the 16th longest river in Sri Lanka. It begins in the hills east of Badulla and flows northeast, emptying into the Indian Ocean south of Kalmunai.
The river was dammed in 1948 as part of the Gal Oya scheme. The dam created the Senanayake Samudra — the largest reservoir in Sri Lanka, at Bintenne. Resettlement of the Tamils and Sinhalese people displaced in this scheme gave rise to among the first ethnic riots in Sri Lanka.
The Gal Oya project resulted in the formation of the 100,000 acre Gal Oya basin. This basin has since been used for cultivating paddy, chillies, sugarcane and potatoes. The Gal Oya National Park in the vicinity has a wide variety of wildlife including bears, leopards and elephants.
Uva Province is Sri Lanka's second least populated province, with 1,259,880 people, created in 1896. It consists of two districts: Badulla and Moneragala. The provincial capital is Badulla. Uva is bordered by Eastern, Southern, Sabaragamuwa and Central provinces. Its major tourist attractions are Dunhinda falls, Diyaluma Falls, Rawana Falls, the Yala National Park and Gal Oya National Park. The Gal Oya hills and the Central mountains are the main uplands, while the Mahaweli and Menik rivers and the huge Senanayake Samudraya and Maduru Oya Reservoirs are the major waterways.
Ampara is the main town of Ampara District, governed by an Urban Council.
Sri Lankan state-sponsored colonization schemes is the government program of settling mostly farmers from the densely populated wet zone in the sparsely populated areas of the dry zone in the North Central Province and the Eastern Province regions near tanks and reservoirs being built in major irrigation and hydro-power programs such as the Mahaweli project to create farming and fishing communities. This has taken place since the 1950s.
The Mahaweli River, is a 335 km (208 mi) long river, ranking as the longest river in Sri Lanka. It has a drainage basin of 10,448 km2 (4,034 sq mi), the largest in the country, which covers almost one-fifth of the total area of the island. The real beginning of Mahaweli Ganga starts at Polwathura(at Mahawila area), a remote village of Nuwara-Eliya District in bank Nawalapitiya of Kandy District by further joining of Hatton Oya and Kotmale Oya. The river reaches the Bay of Bengal on the southwestern side of Trincomalee Bay. The bay includes the first of a number submarine canyons, making Trincomalee one of the finest deep-sea harbors in the world.
The Kotmale River is the longest tributary of Mahaweli River. The river begins as the Agra Oya, in the Horton Plains. The Central Plains have an annual rainfall of between 125 and 200 inches a year. The river is approximately 70 km (43 mi) long and drains a basin of about 58,534 ha. The river flows through a traditional area of ancient villages and tea plantations. King Dutugemunu spent his youth here. The Kotmale Oya flows into the Mahaweli shortly at Pallegama. Tributaries of the Kotmale Oya include the Nanu Oya, the Pundalu Oya, the Puna Oya, and the Dambagastalawa Oya.
Monaragala is a district in Uva Province of Sri Lanka. It is the second largest of the 25 districts in Sri Lanka, with an area of 5,636 km2 (2,176 sq mi).
The 1956 anti-Tamil pogrom, also known as the Gal Oya riots, was the first organised pogrom against Sri Lankan Tamils in the Dominion of Ceylon. It began with anti-Tamil rioting in Colombo, followed by anti-Sinhalese rioting in Batticaloa. The worst of the violence took place in the Gal Oya valley, where local majority Sinhalese colonists and employees of the Gal Oya Development Board commandeered government vehicles, dynamite and weapons and massacred minority Tamils. It is estimated that over 150 people lost their lives during the violence. The police and army were eventually able to bring the situation under control.
The Samanala Dam is a dam primarily used for hydroelectric power generation in Sri Lanka. Commissioned in 1992, the Samanalawewa Project is the third-largest hydroelectric scheme in the country, producing 405 GWh of energy annually. It was built with financial support from Japan and the United Kingdom. It is notable for a large leak on its right bank. Power production continues as planned despite the leakage, and the water from the leak now provides two thirds of the water issued by the reservoir for agriculture in downstream areas.
Gal Oya National Park in Sri Lanka was established in 1954 and serves as the main catchment area for Senanayake Samudraya, the largest reservoir in Sri Lanka. Senanayake Samudraya was built under the Gal Oya development project by damming the Gal Oya at Inginiyagala in 1950. An important feature of the Gal Oya National Park is its elephant herd that can be seen throughout the year. Three important herbs of the Ayurveda medicine, triphala: Terminalia chebula, Terminalia bellirica and Emblica officinalis are amongst the notable flora of the forest. From 1954 to 1965 the park was administrated by the Gal Oya Development Board until the Department of Wildlife Conservation took over administration. The national park is situated 314 km (195 mi) from Colombo.
Lahugala Kitulana National Park is one of the smallest national parks in Sri Lanka. Despite its land area, the park is an important habitat for Sri Lankan elephant and endemic birds of Sri Lanka. The national park contains the reservoirs of Lahugala, Kitulana and Sengamuwa and they are ultimately empties to Heda Oya river. Originally it was designated as a wildlife sanctuary on July 1 of 1966. Then the protected area was upgraded to a national park on October 31 of 1980. Lahugala Kitulana is situated 318 km east of Colombo.
Maduru Oya National Park is a national park of Sri Lanka, established under the Mahaweli development project and also acts as a catchment of the Maduru Oya Reservoir. The park was designated on 9 November 1983. Providing a sanctuary to wildlife, especially for elephants and protecting the immediate catchments of five reservoirs are the importance of the park. A community of Vedda people, the indigenous ethnic group of Sri Lanka lives within the park boundary in Henanigala. The park is situated 288 kilometres (179 mi) north-east of Colombo.
Senanayake Samudraya is the biggest reservoir and man-made lake in Sri Lanka. It is locally known as the sea. Senanayake Samudraya was opened on 28 August 1949 under the Gal Oya Multipurpose Scheme, which was completed in 1953 by D. S. Senanayake.
The Kehelgamu Oya is a major upstream tributary of the Kelani River. The tributary measures 50 km (31 mi) in length, originating from the hills of the Horton Plains National Park, before passing through the Castlereigh Reservoir. Kehelgamu Oya converges with the Maskeliya Oya at Kalugala, forming the 100 km (62 mi) long Kelani River. The river is heavily used for hydroelectric power generation.
The Gal Oya Dam is an embankment dam in the Uva Province of Sri Lanka. The dam creates one of the largest and most iconic 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.
The Deduru Oya Dam is an embankment dam built across the Deduru River in Kurunegala District of Sri Lanka. Built in 2014, the primary purpose of the dam is to retain approximately a billion cubic metres of water for irrigation purposes, which would otherwise flow out to sea. Site studies of the dam began in 2006 and construction started in 2008. It was ceremonially completed in 2014, with the presence of the then President Mahinda Rajapaksa.
The Rambakan Oya Dam is an embankment dam in Maha Oya, Eastern Province, Sri Lanka. The reservoir was designed and constructed by the Sri Lanka Mahaveli Authority and currently functions under the direction of the Ministry of Irrigation and Water Resources Management. It have been created by building an Earthen dam of which is about 1225m in length across the river of Mundeni Aru.
The Mahaweli Development program is known as the largest multipurpose national development program in the history of Sri Lanka and is also considered as the keystone of the government's development program that was initiated in 1961.
The Uma Oya Hydropower Complex (also internally called Uma Oya Multipurpose Development Project or UOMDP) is a irrigation and hydroelectric complex currently under construction in the Badulla District of Sri Lanka. Early assessments of project dates back to 1989, when the first studies was conducted by the country's Central Engineering and Consultancy Bureau. The complex involves building a dam across Dalgolla Oya, and channelling water over a 3,975 m (13,041 ft) tunnel to Mathatilla Oya, both of which are tributaries of the Uma Oya. At Mathatilla Oya, another dam is constructed to channel 145,000,000 m3 (5.1×109 cu ft) of water per annum, via a 15,290 m (50,160 ft) headrace tunnel to the Uma Oya Power Station, where water then discharged to the Alikota Aru via a 3,335 m (10,942 ft) tailrace tunnel. The Alikota Aru is a tributary of the Kirindi Oya.
The Kala Oya is the third longest river in Sri Lanka. It is approximately 145 km (90 mi) in length. The river has a basin size of 2,873 km2 (1,109 sq mi), and more than 400,000 rural population live by the river basin.