The main hydrographic slopes near the Rivière des Frères are: The "rivière des Frères" draws its source from agricultural streams located in the territory of the municipality of Baie-du-Febvre, southeast of the village, northeast of route 255, between chemin du Pays Brûlé and rang de la Grande Plaine.

The "rivière des Frères" flows on 4.0 kilometres (2.5 mi) towards the north-west in an agricultural zone, passing north-east of the village of Baie-du-Febvre, and crosses the route 132.

At the end of the course, the river crosses the firing range of the Ministry of National Defense.

[1] The "rivière des Frères" flows over the "Battures des Frères" on the south shore of Lake Saint-Pierre, downstream from "La Longue Pointe", north-west of the village of Baie-du-Febvre.

The toponym "rivière des Frères" was made official on August 28, 1980, at the Commission de toponymie du Québec.