White Chuck RiverThe White Chuck River is a river in the U.S. state of Washington. It is a tributary of the Sauk River.CourseThe White Chuck River originates on the slopes of Glacier Peak in the Cascade Range, near White Chuck [Cinder Cone]. It flows generally northwest to join the Sauk River south of Darrington. The Sauk River in turn joins the Skagit River, which empties into Skagit Bay, part of Puget Sound.