Carheil Lake (French: Lac Carheil) is a lake in the Côte-Nord region of Quebec, Canada. It is just south of Fermont, and is the source of the Carheil River, which runs south to the Aux Pékans River. The lake has been polluted with phosphorus from wastewater effluent from Fermont, causing algal bloom. This is cause for concern since the lake is among the headwaters for the wild and unspoiled Moisie River.