Tuolumne River

The Tuolumne is really two rivers sharing one name, with the middle skipped. Up high it's a Yosemite wild-trout stream — the Grand Canyon of the Tuolumne, a 33-mile roadless gorge of granite, cascades, and deep pools you reach on foot from Tuolumne Meadows or White Wolf, holding wild rainbows and browns that rarely see a fly. Down low, below La Grange Dam in the foothills east of Modesto, it's an overlooked tailwater — a short stretch of riffles and slow glides where wild rainbows run 12–18 inches with the odd fish past 20 and five pounds in the deeper water. In between, the middle canyon disappears under Hetch Hetchy and Don Pedro reservoirs and San Francisco's plumbing, so the fishery lives at the two ends.

The two ends fish nothing alike. The La Grange tailwater is the cold-season option: when the high country is under snow and a trickle, the lower river holds steady, wadeable flows around 160–170 CFS and stays fishable from the January 1 opener to the October 31 close — sight-nymphing and small dries to spooky, well-fed fish in clear water, best worked stealthily from ten feet back before you wade in. It's technical, not big, and treated as regulated lower-river water rather than a Sierra trout stream. Check flows first: a wet year like 2011 pushed it over 3,000 CFS from January to June and blew it out entirely.

The Grand Canyon is the opposite — a summer-and-early-fall backpacking fishery that only opens once Tioga Road clears, best when flows drop under about 400 CFS, with easy-to-please wild fish on a 3- or 4-weight and attractor dries. The easiest upper water is Tuolumne Meadows itself, right off Tioga Road, where the Dana and Lyell forks join into forgiving brook, rainbow, and brown water ideal for a casual afternoon between hikes. Pressure stays low in the canyon simply because it's work to get there: a wilderness permit and a hard hike, with Pate Valley down at 4,400 feet and the meadows up at 8,600.