The small valley of the Bras Sec is served by a few secondary forest roads, especially for forestry and recreational tourism activities.

The surface of the Dry arm 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.

This landlocked lake between the mountains is located at the southwestern limit of the zec Mars-Moulin, that is to say: From Lac Catellier, the Bras Sec flows over 26.2 km (16.3 mi) with a drop of 341 m (1,119 ft) entirely in the forest zone, according to the following segments: Upper course of the Bras Sec (segment of 18.1 km (11.2 mi)) Lower course of the Bras Se (segment of 8.1 km (5.0 mi)) The Sec arm flows into a bend in the west bank of the rivière du Moulin, near (west side) of Coupau lake.

This confluence is located at: From the mouth of the Sec arm, the current successively follows the course of the rivière du Moulin on 52.7 km (32.7 mi) generally north, then the course from the Saguenay River on 126.1 km (78.4 mi) eastwards to Tadoussac where it merges with the Saint Lawrence Estuary.

The toponym "bras Sec" was formalized on June 29, 1983, at the Place Names Bank of the Commission de toponymie du Québec.