Restigouche River, a river in eastern Canada. From a source about 20 miles (32 km) northeast of Edmundston, New Brunswick, the Restigouche flows northeast to the Quebec border and then east, forming part of the border between the two provinces. The river empties into Cha-leur Bay at Dalhousie. Its total length is 200 miles (320 km). The lower 25 miles (40 km) form a tidal estuary called Escuminac Bay. The Restigouche is noted for its salmon.