Rivière L'Assomption is a significant river system flowing through the Lanaudière region of Quebec, Canada, eventually confluencing with the Rivière des Prairies near the coordinates 45°42'52"N, 73°28'52"W. The river drains a broad watershed that encompasses a diverse mix of agricultural, urban, and natural landscapes, and it supports a surprisingly varied community of fish species that draws anglers from across the region. From its upper reaches down through its lower sections near the St. Lawrence lowlands, the river offers multiple fishing experiences across different habitat types and seasons.