Shoshone Falls

The Snake River here drops two hundred twelve feet over a basalt rim that stretches nearly a thousand feet across, forty-five feet higher than Niagara Falls, and for most of American history utterly unknown to anyone east of the Rockies.

Shoshone Falls was carved by one of the most violent geological events in North American prehistory. About fourteen thousand years ago, an ice dam holding ancient Lake Bonneville collapsed catastrophically, sending a wall of water larger than all of today's Great Lakes combined roaring down the Snake River canyon. That flood scoured the basalt, reshaped the canyon, and left behind the falls you're looking at. For thousands of years afterward, Shoshone people and other tribes gathered here to fish the salmon runs and trade. The falls marked the upper limit of salmon migration on the Snake. Above them, no fish could pass.

European-American explorers documented the falls as early as the eighteen forties, and they became a tourist destination almost immediately. By the eighteen seventies, steamboats brought visitors up from Portland on the Columbia River, and the falls had acquired their grand nickname: the Niagara of the West.

Then irrigation arrived. On March first, nineteen oh five, a contractor named Frank Buhl pulled the wheel on a headgate at Milner Dam, twelve miles upstream. The Snake River was diverted into a thousand miles of irrigation canals across Magic Valley, and that night Shoshone Falls went dry. The surrounding desert bloomed into farmland. The falls returned only in wet years, when irrigation canals could not absorb the full flow.

Today the falls run at their full volume in late winter and early spring, roaring back to something like their primeval self before the irrigation season pulls the river down again. It is a seasonal rhythm between spectacle and silence that Idaho has lived with for over a century.