Lake Cascade (or originally “Cascade Reservoir”) is located on the North Fork of the Payette River in Valley County, Idaho, USA, in the Boise National Forest. It is the fourth largest lake or reservoir in the state. The closest cities are Cascade, Donnelly, and McCall.The lake contains perch, trout, smallmouth bass, Kokanee, and Coho Salmon for anglers and there is a winter ice fishing beautiful season.
Lake Cascade State Park has several units around the lake.The lake experienced a bloom of blue-green algae in 1993 caused by low water, high phosphorus content, and hot weather. Studies of water quality found phosphorus to be present in high levels which contributed to the algal bloom. The defunct Tamarack Resort (2004–09) is located on the west shore of the reservoir, southwest of Donnelly. The term "Lake Cascade" came into use during this time period.