I spend Most of My fishing time on the rivers in the great state of Idaho. There are no shortages of First class trout streams here. From the top to bottom of the state there are great opportunities to hook trout. If there is flowing water there are probably a lot of trout in it. Fly fishing in Idaho is something everyone should probably do at least once. This state is an example of great western US flyfishing paradise.
I have added several Idaho trout fishing locations on the map below, but I have not even come close yet to having every great trout fishing river listed. No matter where you are in this state there will be trout fishing available to you within an hour drive. The Idaho trout fishing rivers I have listed below are rivers that I have found to be great locations and they all have a lot of good access areas. Some of the rivers below are more for the wade fisherman and other bigger rivers such as the south fork of the snake are almost exclusively fish-able by boats. See: Boat launches on the South fork of the Snake river here.
Check here at USGS for up to date current water level information for nearly every river in the State of Idaho.
Silver creek has some pretty nice fish in it. I fished a couple sections of this river this past summer and caught some beauties. If you are looking for an ultra clear and technical dry fly river this is it. The fish in this clear creek are very skittish and well educated. Much of this river is tight and hard to cast outside of roll casting. Small dry flies and perfect presentations are required to catch nice fish here. This is a challenging fishery, but if you are up for the challenge, I recommend giving Silver creek a try.
The wild Lochsa River runs between the Selway-Bitterroot Wilderness Area and the last remaining roadless portion of the entire Lewis and Clark Trail. Here, in the mountains of north-central Idaho, the river and its valley look much as they did in 1805 This is an amazing place, with solitude and peace unmatched anywhere else in the lower 48.
The Salmon River remains one of the most free-flowing waterways in America. Set against rugged mountains and grassy meadows, the river makes a fantastic backdrop for fishing trips for those who prize beauty and adventure.
Its headwaters originate in the Sawtooth and Salmon River Mountains at elevations over 10,000 feet. Fishing can get pretty good on the payette.
The Boise River Watershed is one of Idaho’s best-kept secrets. The Boise River winds through the heart of the City of Boise, Idaho’s capital.
Owyhee River is just an hour away from Boise, Idaho However it seems like a world away when fly fishing for rising trout in the deep, desert canyon.
This is a popular area for wading. It gets good hatches and is easily accessible.
This section near Lorenzo has a different feel to it than the upper river. There are a large number of brown trout in this area. (more so than upstream) They will sit in shallow water slowly sipping flies, and eating nymphs. This area is more wade-able than the upper sections do to a large number of side channels and braids. Access is tough without a boat, although with hiking it can be done.
The Clearwater gets a run of steelhead and has plenty of local trout to hook. This is a big river, and has some wading available. Although a drift boat is ideal.
To properly fish this you will need a drift boat, and a person who knows how to row it. There is some wade fishing in the fall/winter after the water goes down. Summer and spring, you WILL need a boat to catch trout. The South fork of the snake has a very large wild trout population and hooking 20" plus trout is very common. It has a good population of Rainbows, brown trout and a lot of cutthroat. Fish with the hopper dropper rig for the best results. During the late spring and summer the fish are often eager to eat larger dry flies (Chernobyl ants). Drop a nymph or two on 3-4x tippet about 3 feet and you should have success.
Another slow water dry fly fishery. No slapping the water, and only cast to actively feeding fish and you can hook some giants here. There are plenty of wading opportunities on the Henry's fork in this area. These fish are well educated and will be put down easily by sloppy casts and dragging drifts. Bring a large assortment of small dry flies and perhaps even some 6x. A large boat launch at Osborne bridge just south of Island Park, ID gives good access to wading and easy drift boat launching. This river has a lot of grass on the bottom and the bigger fish will quickly entangle you in it if you aren't careful. Bring your 6 weight and be ready for some true trophy trout. It is not uncommon to catch fish nearing the 30" mark in this area. The main question is: Can you get them to hit your fly?