A Checklist of the 36 Major Rivers of Sri Lanka

1
DEDURU OYA
At one hundred and forty-two kilometres, the Deduru Oya is the country’s fifth equal longest river, collecting its waters in the Gommuna Mountains near Kurunegala, the start of a catchment area one and a half thousand square kilometres in size. Harnessed by massive hydroelectric structures and vast reservoirs and fed by over three thousand million cubic metre of rain annually, it delivers over a quarter of its total water to the sea at Chilaw on the eastern seaboard, to feed the brackish lagoons for which Chilaw is famous and where live – perhaps, still – that most elusive and endangered of sea beasts, the dugong.

2
GAL OYA
At one hundred and eight kilometres, the Gal Oya is the country’s sixteenth longest river, collecting its waters in the mountains around Badulla, a town built on tea. The town is also home to two of the country’s most notable shrines: Muthiyangana temple, one of the sixteen places on the island that Buddhists believe to have been visited by the Lord Buddha himself; and the Badulla Kataragama Devalaya, a shrine dedicated to Kataragama, a Tamil goddess who transitioned into Buddhism. The river flows out into the Indian Ocean near the Eastern Province town of Kalmunai, a place noted for its Muslim community. The river’s journey is as fine a meander through the country’s varied religions traditions as it is possible to have

3
GIN GANGA
At one hundred and thirteen kilometres, the Gin Ganga is the country’s fourteenth longest river, collecting its cool waters from the mountains around the Sinharaja Forest. The Gin Ganga flows south, pausing briefly at Thelikada where it has been dammed to create a reservoir, before flowing towards Gintota, a little village near Galle famous for where many of the country’s plywood tea chests are made.

4
KALA OYA
At one hundred and forty-eight kilometres, the Kala Oya is the country’s third longest river, collecting its waters in the Omaragolla Mountains in the centre of the island and snaking its way through the flat dry zone to drain into the Puttalam Lagoon near Kalpitiya. At Kalpitiya its seeps out into the ocean through reefs, saltpans, mangroves swamps, and marshes creating an environment perfect for nature spotters of all sorts.

5
KALU GANGA
At one hundred and twenty-nine kilometres, the Kalu Ganga is the country’s tenth longest river, collecting its waters in Seetha Gangula near Adam’s Peak, moving on to flow through Sinharaja, Ratnapura, Richmond Castle, and the western seaboard at Kalatura, home to the mangosteen.

6
KELANI GANGA
At one hundred and forty-five kilometres, the Kelani River is the country’s fourth longest river. As Colombo has grown exponentially, the river has become ever more its work horse, used for everything from sewage disposal and mining to hydroelectricity production, transport and – of course the supply of (in this case) eighty percent of the city’s water needs.

7
KIRINDI OYA
At one hundred and seventeen kilometres, the Kirindi Oya is the country’s eleventh longest river, collecting its waters in Namunukula. The Kirindi Oya then flows out into the Indian Ocean at Bundala, whose almost 4,000 square hectares of wetland supports a glamorous roll call of rare native and distinguished international visitors, including the always-welcome but increasingly rare pink flamingo.

8
KUMBUKKAN OYA
At one hundred and sixteen kilometres, the Kumbukkan Oya is the country’s twelfth longest river, collecting its waters near of Lunugala and flowing out into the India Ocean at Kumana National Park through a series of lagoons and tanks of shallow brackish water.

9
MADURU OYA
At one hundred and thirty-six kilometres, the Maduru Oya is the country’s eighth longest river, collecting its waters in the mountains beyond Mahiyanganaya, halfway from Kandy to the Indian Ocean at Batticaloa. The river drains out at Kalkudah, a small town surrounded by beaches still abandoned since the ending of the civil war.

10
MAHA OYA
At one hundred and thirty-five kilometres, the Maya Oya is the country’s ninth longest river, collecting its waters in the Rakshawa Mountains. It supplies water to such major centres as Kurunegala, Gampaha, and Kegalle and providing, en route, multiple sites for sand, and clay mining. It flows out on to the western seaboard near Negombo at Kochchikade.

11
MAHAWELI RIVER
At three hundred and thirty-five kilometres, the Mahaweli River is, by a long shot, the country’s greatest river. Twice as long as its nearest rival, it winds down from Horton Plans, through Kandy before its jubilant union with the ocean at Trincomalee.

12
MALVATHU RIVER
At one hundred and sixty-four kilometres, the Malvathu River is the country’s second largest river. Spiling from the streams of the Inamaluwa Mountains around Dambulla and Sigiriya, it flows onto Anuradhapura, connecting it with Mannar.

13
MENIK GANGA
At one hundred and fourteen kilometres, the Menik Ganga is the country’s thirteenth longest river, collecting its waters in Namunukula and draining then out at Yala via Kataragama, and into the Indian Ocean, offering to Neptune just ten percent of the waters it has captured along its way.

14
MI OYA
At one hundred and nine kilometres, the Mi Oya is the country’s fifteenth longest river, collecting its waters in the flatlands halfway between Kurunegala and Anuradhapura. Although it receives over one and a half thousand cubic metres of rain a year in a catchment area of over a thousand square kilometres, it releases a mere three percent of what it gains into the Palk Straights on the western seaboard near Puttalam.

15
WALAWE RIVER
At one hundred and thirty-eight kilometres, the Walawe River is the country’s seventh longest river, collecting it waters off Adams Peak at Belihul Oya. It is an area of waterfalls one, the Bambarakele Ella, the highest in the land at over eight hundred and sixty feet high. The river drains out into the Indian Ocean at Ambalantota, once the great port city of the ancient Kingdom of Ruhuna.

16
YAN OYA
The Yan Oya, at 142 kilometres, is the island’s fifth-longest river. It begins near Polonnaruwa and follows the Mahaweli further north to spill out onto the remote beaches of Pulmoddai whose black sand, unmined since the civil war, contains large deposits of ilmenite rutile and zircons.


COLOSSAL

1.MAHAWELI RIVER - 335 KM) RUNNING FROM HORTON PLAINS TO TRINCOMALEE.


CAPACIOUS

2.MALVATHU RIVER - (164 KM) RUNNING FROM THE INAMALUWA MOUNTAINS TO VANKALAI.
3.KALA OYA - (148 KM) RUNNING FROM THE OMARAGOLLA MOUNTAINS TO KALPITIYA NORTH.
4.KELANI RIVER - (145 KM) RUNNING FROM BATHTHULU OYA TO COLOMBO.
5.YAN OYA - (142 KM) RUNNING FROM RITIGALA TO PULMODDAI.
6.DEDURU OYA - (142 KM) RUNNING FROM THE GOMMUNA MOUNTAINS TO CHILAW.
7.WALAWE RIVER - (138 KM) RUNNING FROM BELIHUL OYA TO AMBALANTOTA.
8.MADURU OYA - (135 KM) RUNNING FROM THE AKURUGALA MOUNTAINS TO KALKUDAH.
9.MAHA OYA - (134 KM) RUNNING FROM THE RAKSHAWA MOUNTAINS TO KOCHCHIKADE.
10.KALU GANGA - (129 KM) RUNNING FROM SEETHA GANGULA TO KALUTARA. GOODLY
11.KIRINDI OYA - (117 KM) RUNNING FROM NAMUNUKULA TO BUNDALA.
12.KUMBUKKAN OYA - (116 KM) RUNNING FROM LUNUGALA TO KUMANA.
13.MENIK GANGA - (114 KM) RUNNING FROM NAMUNUKULA TO YALA.
14.GIN GANGA - (113 KM) RUNNING FROM THE KABARAGALA MOUNTAINS TO GINTOTA.
15.MI OYA - (109 KM) RUNNING FROM THE KUDA MADAGALA MOUNTAINS TO PUTTALAM.
16.GAL OYA - (108 KM) RUNNING FROM THE HEWA ELIYA MOUNTAINS TO OLUVIL.


LARGE

17.ATTANAGALU OYA - (76 KM) Running From The Kegalle District To The Negombo Lagoon.
18.NILWALA GANGA - (72 KM) Running From The Rakwana Mountains Into The Indian Ocean.
19.KANAKARAYAN ARU - (70 KM) Running From Semamadu Kulam To The Chundikkulam Lagoon.
20.KOTMALE RIVER - (70 KM) Running From Horton Plains National Park Into The Mahaweli River.
21.PARANGI ARU - (60 KM) Running From Near Vavuniya Into The Palk Strait.
22.KEHELGAMU OYA - (50 KM) Running From Horton Plains Into The Kelani River.
23.PALI ARU - (50 KM) Running From Puliyankulam Into The Palk Strait.


MODERATE

24.MASKELIYA OYA - 40 KM) Running From The Peak Wilderness Sanctuary Into The Kelani River.
25.NAY ARU - (40 KM) Running From Near Vavuniya Into The Palk Strait.
26.PER ARU - (32 KM) Running From Vavuniya To The Nanthi Lagoon.
27.MANDEKAL ARU - (30 KM) Running From Near Mullaitivu Into The Palk Strait.
28.NANU OYA - (27 KM) Running From Pidurutalagala Into The Kotmale River.
29.PALLAVARAYANKADDU ARU - (27 KM) Running From Near Mullaitivu To The Palk Strait.


SMALL

30.AKKARAYAN ARU - (25 KM) Running From Near Mullaitivu To The Jaffna Lagoon.
31.NETHELI ARU - (24 KM) Running From Near Mullaitivu To The Chundikkulam Lagoon.
32.THERAVIL ARU - (23 KM) Running From Near Mullaitivu To The Chundikkulam Lagoon.
33.NAY ARU - (20 KM) Running From Near Mullaitivu To The Nai Aru Lagoon.
34.PIRAMENTHAL ARU - (20 KM) Running From Near Mullaitivu To The Chundikkulam Lagoon.
35.KODALIKKALLU ARU - (19 KM) Running From Near Mullaitivu To The Nanthi Lagoon.
36.VALUKKAI ARU - (16 KM) Running From Near Jaffna To The Jaffna Lagoon.