The river rises in the Sandilands Provincial Forest near Steinbach and passes by or through the communities of Marchand, La Broquerie, Ste.

Anne, and Lorette before reaching the Red River Floodway near the Winnipeg city limits.

Within the city, the Seine travels a tortuously meandering course, reaching the Red River at St. Boniface just north of The Forks.

It is a typical meandering river with a single main channel embanked within a flat, shallow valley.

The river's banks are heavily treed, but pollution has been an issue in the city of Winnipeg.