The rivière des Mares is a tributary of the west bank of the lower part of the Rivière du Gouffre, flowing entirely in the town of Baie-Saint-Paul, in the Charlevoix Regional County Municipality, in the administrative region of Capitale-Nationale, in the province from Quebec, to Canada.

The water level of the river varies with the seasons and the precipitation; the spring flood generally occurs in April.

The latter takes its name from a small body of water located at the bottom of the valley.

The use of the name "Rivière de la Mare" is old since it is found mentioned in the delimitation of the lands of Baie-Saint-Paul in 1716.

[2][3] The toponym "Rivière des Mares" was formalized on March 25, 1997, at the Place Names Bank of the Commission de toponymie du Québec.