Caniapiscau River, river in Nord-du-Québec region, northern Quebec province, Canada. Rising from Lake Caniapiscau in central Quebec, it flows generally northward for 460 miles (740 km) to its junction with the Larch River, discharging into Ungava Bay via the 85-mile- (137-kilometre-) long Koksoak River. Its name is an Indian word meaning “rocky point.” Flowing for some 200 miles (320 km) through a cataract-ridden gorge, the Caniapiscau has tremendous hydroelectric power potential within easy reach of the Labrador–Ungava iron-ore mining region.