| Deduru Oya | |
|---|---|
 Aerial view of the mouth of Deduru River, Chilaw. | |
  | |
| Physical characteristics | |
| Source | |
| • location | Kurunegala District |
| Mouth | |
• location | Chilaw |
• coordinates | 07°36′50″N 79°48′12″E / 7.61389°N 79.80333°E |
• elevation | Sea level |
| Length | 142 km (88 mi) |
| Basin size | 2,620 km2 (1,010 sq mi) |
The Deduru Oya is the sixth-longest river of Sri Lanka. The 142 km (88 mi) long river runs across four provinces and five districts.
Its catchment area receives approximately 4,313 million cubic metres of rain per year, and approximately 27 percent of the water reaches the sea. It has a catchment area of 2,620 square kilometres.[1]