In 1882, the post office opened, using the English name Lake St. Mary and renamed to Lac-Sainte-Marie in 1916.

Ninety percent of the village had to be relocated to higher ground, including the church (St-Nom-de-Marie parish) located in the centre of the old town.

[4] St-Nom-de-Marie parish was built in 1904-1905 and then moved to its actual site because of the Paugan dam construction, completed in 1929.

[4] The submerged town attracted the attention of many tourists from the cities of Ottawa and Gatineau, and in 1975, Lac-Sainte-Marie became the official name, which paid tribute to a forgotten pioneer, Marie Léveillée, mother of Jean-Marie Léveillée who was the first settler in the area.

[1] Private dwellings occupied by usual residents (2021): 374 (out of 930 total)[3] Mother tongue languages (2021):[3]