The lower part of the Couchepaganiche river valley is served by the route 169 which runs along the southeast shore of lac Saint-Jean.

The surface of the Couchepaganiche River is usually frozen from the beginning of December to the end of March, however the safe circulation on the ice is generally made from mid-December to mid-March.

This confluence is located at: From the mouth of the Couchepaganiche river, located on the southeast shore of Lake Saint-Jean, the current crosses this lake north on 17.6 km (10.9 mi), then follows the course of the river Saguenay via the Petite Décharge on 172.3 km (107.1 mi) to Tadoussac where it merges with the Saint Lawrence estuary.

In his deposition of 1823, the explorer François Verreault affirms that this small river is called "Koushpygish", Innu term meaning "where the water rises a little".

[2] The toponym “Rivière Couchepaganiche” was formalized on December 5, 1968, at the Place Names Bank of the Commission de toponymie du Québec.