The Piponisiw River is a tributary of Simard Lake (Gouin Reservoir) located in the western part of the Gouin Reservoir, flowing entirely into the forest zone in the town of La Tuque, in the administrative region of Mauricie, Quebec, Canada. The Piponisiw River flows successively in the canton of Lacasse. Forestry is the main economic activity of this valley; recreational tourism activities, second. The surface of the Piponisiw River is usually frozen from mid-November to the end of April, however, safe ice circulation is generally from early December to late March.