 | This article may require cleanup to meet Wikipedia's quality standards. The specific problem is: latitude and longitude need rounding down per WP:COORDS to more realistic values: 0.000001° is 100 millimetres and 0.000000000001° is 100 nanometres. (April 2020) |
| L'Assomption River Rivière L'Assomption | |
|---|---|
_2005-08-22.jpg) Assomption River at Chutes Monte-à-Peine Park in Matawinie Regional County Municipality | |
 | |
| Location | |
| Country | Canada |
| Province | Quebec |
| Region | Lanaudière |
| Physical characteristics | |
| Source | L'Assomption Lake |
| • location | Saint-Guillaume-Nord |
| • coordinates | 46°27′45″N 74°03′16″W / 46.46250°N 74.05444°W |
| Mouth | Rivière des Prairies |
• location | Repentigny |
• coordinates | 45°42′52″N 73°28′51″W / 45.71444°N 73.48083°W |
| Length | 200 km (120 mi) |
| Discharge | |
| • location | Rivière des Prairies |
The Assomption River (in French Rivière l'Assomption, named after the Assumption of Mary) is the most important waterway in the Lanaudière region of Quebec, Canada. It is over 200 kilometres (120 mi) long, and has a drainage basin (watershed) of 4,220 square kilometres (1,630 sq mi). Its source is the Mont Tremblant massif. Seven significant rivers flow into the Assomption (de la Boule, Versailles, Noire, la Chaloupe, Ouareau, Saint-Esprit, and Achigan) before it flows into the Rivière des Prairies at Repentigny, Quebec.
About 150,000 people live in the drainage area of this river.