It flows in the municipalities of Saint-Agapit and Saint-Apollinaire in the Lotbinière Regional County Municipality, in the administrative region of Chaudière-Appalaches, in Quebec, in Canada.

The main neighboring watersheds of the Red River are: The Red River has its source in the municipality of Saint-Agapit, on the boundary with the municipality of Saint-Apollinaire.

This head area is located south of highway 20, southeast of the village center of Saint-Apollinaire and north-west of the village of Saint-Agapit.

From its source, the Red River flows over 10.3 kilometres (6.4 mi) divided into the following segments: The Red River empties on the west bank of the Beaurivage River north of the hamlet "Pointe-Saint-Gilles", in Lévis.

The toponym "rivière Rouge" was made official on October 6, 1983, at the Commission de toponymie du Québec.