 With a wide network, Tremblay decided to enter politics and was elected in 1996 as mayor of the city of Chicoutimi, serving from 1997 to 2001.Tremblay strongly supported the 21st-century merger of seven municipalities (Chicoutimi, Jonquière, La Baie, Laterrière, a portion of the territory of Canton-Tremblay, Lac Kénogami and Shipshaw) into a new city, later named Saguenay.His office issued the document entitled "Le courage de changer les choses" (The Courage to Change Things), to explain the benefits of creating the new city of Saguenay through improved administration and cost savings, and gained the support of regional voters for the measure.