2020 Map of Big Lost River Sinks

About this map

The Lemhi Range terminates into the desert floor here, where the hydrology of Butte County takes a peculiar turn. The map documents the Big Lost River Sinks, a terminal drainage point where surface water vanishes into the volcanic aquifer of the Snake River Plain. This arid landscape is defined by the Dry Channel Big Lost River, which cuts across the terrain as a reminder of the seasonal and historical water flow that once reached these flats more frequently. Human activity is sparse and primarily limited to utility and transport corridors like Lincoln Blvd and Cinder Butte Rd, which navigate the open land south of the mountains. The map provides a clear view of the public land survey system divisions, including t6n r30e and t5n r31e, illustrating the vast, unpopulated character of this high-desert region.