The course of the Bras de Jacob Ouest crosses the northwest part of the zec Mars-Moulin.

A few other secondary forest roads serve the valley of the Bras de Jacob Ouest, especially for forestry and recreational tourism activities.

The surface of Bras de Jacob Ouest is usually frozen from the beginning of December to the end of March, however the safe circulation on the ice is generally done from mid-December to mid-March.

The main watersheds adjacent to the Bras de Jacob Ouest are: The Bras de Jacob Ouest rises at the mouth of Lac Graveline (length: 0.5 km (0.31 mi); altitude: 410 m (1,350 ft)) in a forest area in the Laurentides Wildlife Reserve.

This confluence is located at: From the mouth of Bras de Jacob Ouest, the current successively take the courses of Bras de Jacob on 9.0 km (5.6 mi) towards the east, the course of the rivière du Moulin on 37.6 km (23.4 mi) towards the north, then the course of the Saguenay River on 126.1 km (78.4 mi) towards the east until at Tadoussac where it merges with the Saint Lawrence Estuary.