The accident occurred in Saint-Hippolyte at about 5:30 p.m. when the driver was unable to stop the car on a slope due to the icy road, while trying to access a private entrance on 305th Avenue.
The car slid off the road and into Lac de l'Achigan, where the driver managed to exit the vehicle and attempted to rescue Péladeau.
Firefighters and police officers were called to the scene, where they managed to free 55-year-old Péladeau from the vehicle and attempt resuscitation.
Péladeau was pronounced dead when she was taken to hospital.
The driver survived and was also transported to hospital.
Investigators with la Sûreté du Québec said they will interview the driver to establish in more detail the cause of the fatal accident.
Isabelle Péladeau is the daughter of Quebecor Inc. founder Pierre Péladeau and sister to the chairman of Hydro-Québec's board of directors, Pierre Karl Péladeau.
Quebecor Inc. owns Quebec's main tabloid papers and private TV network, along with the Sun Media chain in English Canada.Suggest a correction