Shoshone Falls

Shoshone Falls runs on a timetable. Twenty-four miles upstream, Milner Dam sends most of the Snake into the canals that made the Magic Valley, and in late summer the riverbed below it can run dry. Directly above the falls, Idaho Power's plant has taken its share since 1907. What spills over the 212-foot rim is whatever is left.

In a big snow year that can be more than 20,000 cubic feet a second, a wall of water across the whole canyon; a typical spring peaks around 10,000 to 12,000. After that the utility is bound only to a daytime "scenic flow" of 300 cubic feet a second from April through Labor Day, and in dry years even that is hard to find. The falls you see depend less on this week's weather than on water rights filed a century ago.

The best shows now come from an odd source. Each spring, and often again in early summer, the Bureau of Reclamation releases stored water from the upper Snake to help young salmon and steelhead down the lower Snake and Columbia to the sea. For a few weeks that water pours over the one barrier no salmon ever climbed, the falls that marked the upper end of the runs for the Newe who fished below them.

The City of Twin Falls runs the park on the south rim east of town, with an overlook platform, a rim trail and a day-use fee per vehicle. Check the posted flow before driving out. Late September sometimes brings a second rise, when the irrigation season ends and the canals stop drawing.