The Rivière à Mars is a tributary of the Baie des Ha! Ha! Crossing the borough La Baie, in Saguenay (city), in the administrative region of Saguenay–Lac-Saint-Jean, in Quebec, in Canada. The "rivière à Mars" is a tributary of the Saguenay River and has its source in the Laurentides Wildlife Reserve. This river to salmons was badly affected by the Saguenay Flood which occurred from July 19 to 21, 1996.