Henry’s Fork of the Snake River
By, Robert Deen
The perfect river designed by a committee of dry fly fisherman would look very much like the Henry’s Fork of the Snake River.
The headwaters of the Henry’s Fork begin at the edge of the continental divide in Idaho – ultimately flowing to the Pacific. Just 10 miles across the continental divide are the headwaters of the Missouri – the Red Rock and Madison rivers – that flow to the Gulf of Mexico.
The Henry’s Fork country encompasses 1.7 million acres and over 3,000 miles of rivers and streams in eastern Idaho and western Wyoming. Henry’s Fork is best known for big, wild rainbows and browns. The river is a fly fisherman’s dream, flowing through scenic canyons and gentle ranch country.
Rainbow trout were introduced into the watershed in the late 1800s. Unfortunately they gradually replaced the region’s native cutthroat trout, although efforts are currently underway to restore the Yellowstone cutthroat.
In addition to wild rainbow trout, the lower river (below Mesa Falls to the confluence with the main stem of the Snake) is particularly known for excellent brown trout fishing. Browns are a fairly recent addition, introduced in the early 1980s by local fisherman and Trout Unlimited. The Idaho state record brown trout was caught on the lower Henry’s Fork in 2008, weighing in at 27 pounds 3 ounces.
Brook trout – introduced in the late 1800’s from the east coast – are present in more stream miles in the Henry’s Fork watershed than any other trout species. Brookies have displaced cutthroat trout from most headwater streams, and rarely exceed 8 inches in the small, cold streams they frequent.
Like most rivers in the Mountain West, fishing conditions can depend on snowfall. In March and April snow will melt in the lower valleys while continuing to fall in the high country. Fishing can be at its best before the major snowmelt run-off. In a typical year most snow will melt by late May and the rivers will run full. By June weather and river conditions are near perfect.
The Henry’s Fork of the Snake River is named for Colonel Andrew Henry, a fur trader for the Missouri Fur Company that entered the Snake River plateau in 1810. He explored the Idaho-Montana wilderness, discovered the lake that also bears his name, and established the Fort Henry trading post on the upper Snake River.
A great source of information is the Henry’s Fork Foundation – a non-profit dedicated to preserving the river and its outstanding fishing. The website offers fishing reports and a “hatch chart” anglers can use to determine what insects the trout may be feeding on at any given time and place. It also provides trip-planning information including maps and a directory of local services.
The website for the Three Rivers Ranch offers a boat access map and hatch charts for the Lower Henrys and the Upper Henry’s.
The Henry’s Fork watershed without doubt offers some of the best fly fishing in the United States – some would say in the world. If you’re a fly fisherman, you owe it to yourself to give it a try.