 Its mouth is to the southwest of the Baie des Sept-Îles.During the Holocene the Sainte-Marguerite created a delta of thick paraglacial and post-glacial sediments that completely cover the glacial landforms and glaciomarine deposits near the river mouth.The river mouth today is a haven for small boats during bad weather in the Gulf, because the basin that it forms is protected by the Pointe Sainte-Marguerite.