Longest Rivers In Sri Lanka

Rivers in Sri Lanka include the Kelani, which flows through the capital city of Colombo.
Rivers in Sri Lanka include the Kelani, which flows through the capital city of Colombo.

Sri Lanka is a country in South Asia located south of India. The Mahaweli, Sri Lanka’s longest river, flows for 208 miles between the central highlands and the Bay of Bengal. Sri Lanka boasts 103 river basins and, through the use of modern technologies, some of these rivers are being regulated by use of dams and reservoirs. Most of Sri Lanka’s land mass is arid, and the rivers are important for irrigation and water supply.

Longest Rivers In Sri Lanka


The Mahaweli River flows from the Hatton Plateau in the country’s western region to the Bay of Bengal and covers a distance of 208 miles. The river has supplied water for agriculture in the adjacent areas throughout centuries. A network of dams was constructed starting in the 1970s to siphon large quantities of water for irrigation in the surrounding sands. The river has also been tapped to supply hydroelectric power in the country. The river is home to numerous freshwater fish species, and it supports pockets of plantations and grassland along its shores as well as flowering plants and ferns. Major threats to the river include pollution, human encroachment, alien species, illegal development in the river’s reservation region, and excess hydropower projects.

Malvathu River

The Malvathu River flows for 102 miles from the North Central Province to the Palk Strait. The city acts as a link between Anuradhapura City and Mannar Coast. Anuradhapura was Sri Lanka’s capital for more than 15 centuries and the ancient Kings commissioned the construction of canals on the river to feed the rice plantations and sustain the population. The river thus has historical significance in Sri Lanka. The river’s aquafauna is being threatened by pollution and increased sedimentation.

Kala Oya

Kala Oya River flows for 92 miles from Dambulla to Wilpattu in northwestern Sri Lanka. The river gets about 75% of its water from the Mahaweli River and the rest from rainfall. The river’s catchment area gains an estimated 3,169 million cubic meters of rain annually. Water in the river’s lower basin is primarily tapped for rice irrigation, which is done both in large and small scale. Nearly 65% of the river’s water is diverted to large-scale irrigation projects.


Kelani River flows for 90 miles from the Sri Pada Mountain Range in the country’s central region to Colombo. The river has religious and cultural significance to the inhabitants of Kelani Valley, who observe the Sinhala Buddhist traditions of the country. A Kelani temple stands on the river’s banks, and it is revered as a sacred site. Throughout its course, the river sustains the livelihood of many people as it is used for fishing, irrigation, and transportation. The river also contributes a significant portion of Colombo’s power requirements through the hydropower stations built along its course. Sand mining is done along the river’s shores, and it has had negative impacts on the river’s health. The river is also threatened by pollution and urban development.

Other Rivers in Sri Lanka

The rest of Sri Lanka’s rivers are Yan Oya (88 mi); Deduru Oya (88 mi); Walawe Ganga (86 mi); Maduru Oya (84 mi); Maha Oya (83 mi), and Kalu Ganga (80 mi). The rivers in Sri Lanka are continuously threatened by invasive species, domestic and industrial pollution, deforestation, habitat degradation, and use of pesticides.

Longest Rivers In Sri Lanka

RankLongest Rivers in Sri LankaLength
208 miles
2Malvathu102 miles
3Kala Oya92 miles
4Kelani90 miles
5Yan Oya88 miles
6Deduru Oya88 miles
7Walawe Ganga86 miles
8Maduru Oya84 miles
9Maha Oya83 miles
10Kalu Ganga80 miles

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