At the base of Palisades Dam, the Snake River becomes the legendary South Fork, and for the next 16 miles or so, the “upper river” flows through the idyllic alpine country of Irwin and Swan Valley. It’s one the most iconic stretches of river in the American West. Tight and fast in some reaches and wide and sweeping in others, it’s the river other rivers wish they could be.
Big, tailwater browns, rainbows and cutthroats can be pulled from the river using nymph rigs and streamers — this is big-fish water loaded with oxygen and food, like mysis shrimp, that pumps into the river from Palisades Reservoir. It’s also cold, even on the hottest summer days, because it enters the river from the chilly depths of the lake.
Below the confluence with Palisades Creek, the river tightens up a bit, and for the next four or five miles, it becomes an intimate float where anglers can throw dries at the banks.
During the salmonfly hatch in late June and into July, and again in August and into September, when big terrestrials are around, anglers can throw big dry flies for large, aggressive trout.
The river opens up, coursing its way over a braided network of riffles and runs and breaking into smaller channels and backwater sloughs. Here is where anglers will see the iconic Fall Creek Falls, and on this stretch of river, anglers can get out of the boat and enjoy some of the best walk-and-wade fishing for wild trout anywhere in the West.
Right around the Spring Creek Bridge, the river comes back into a tighter route, but it still sports plenty of character. This 2-mile stretch is serious trophy trout water. Depending on the time of year and what’s hatching, this reach, from the bridge to the takeout just below South Fork Lodge, can make a great day on the river absolutely unforgettable.