The Henry’s Fork watershed in eastern Idaho and western Wyoming encompasses 1.7 million acres and over 3,000 miles of rivers, streams and canals. High mountain streams and warm natural springs form the headwaters of the Henry’s Fork of the Snake River, which flows through deep canyons as it descends to the agricultural land of the upper Snake River Valley. This rich watershed supports healthy populations of fish and wildlife, including several threatened and endangered species, as well as high-quality recreational experiences.

 

There are about 40,000 people who live in four Idaho counties in the watershed — Fremont, Teton, and parts of Madison and Clark— plus the southwest corner of Yellowstone National Park and west slope of the Teton Range in Teton County, Wyoming. Mormon and Lutheran homesteaders, who originally settled the basin, built irrigation canals and storage reservoirs for water in the late 1800s. Canals divert water from the Henry’s Fork, Fall River, Teton River and smaller tributaries, and dams built on Henry’s Lake Outlet and the Henry’s Fork store irrigation water. Over 235,000 acres of farmland are irrigated from surface or groundwater sources in the basin; potatoes and grains are the primary crops. Other important sectors of the economy include recreation and tourism services, government, timber products and livestock.