It receives the Teton River from the east approximately west of Rexburg. It joins the Snake from the northeast approximately southwest of Rexburg, just below . Island Park Reservoir, a component of the Minidoka Project, is used for irrigation in the Snake River Plain. Its drainage provides one of the most important rainbow trout fisheries in Idaho in terms of habitat, fish populations, and use by anglers. The section of the river between Henry's Lake and Big Springs is a major spawning area for trout and is closed to fishing. Henrys Fork has long been noted for its superb fishing, especially its dry fly fishing. Bing Lempke, a pipefitter from nearby Idaho Falls, was considered the local dean of the fishery, until he died in 1990.