Little Lost River
General data
- Name: Little Lost River
- Water system: Columbia River
- Water type: River
- Progression: Snake River (Columbia River tributary) -> Lake Wallula -> Columbia River -> Columbia River Estuary -> Pacific Ocean -> Planet Earth
- Climates: Temperate
- Continents: North America
- Countries: United States of America
The Little Lost River is a river in the central part of the U.S. state of Idaho. It is approximately 49 miles (79 km) long and drains an arid farming valley, the Little Lost River Valley, bordered by the Lost River Range on the west and Lemhi Range on the east.
Instead of emptying into a larger body of water, it disappears into the ground at the edge of the Snake River Plain, a phenomenon that gives it its name. The water feeds into the Snake River Aquifer, eventually reaching the Snake River through a series of springs farther west.