1956 Map of Obsidian Butte

About this map

Salton Sea National Wildlife Refuge dominates this mid-century survey, documenting the expansive shoreline and engineering of the Imperial Valley basin. Recorded during a period when the water level stood at elevation 235 feet below sea level, the map reveals a landscape defined by an intricate network of irrigation and drainage infrastructure including the Estelle Drain, Vail Cut Off Drain, and numerous controlled laterals. The prominent volcanic landform Obsidian Butte stands near the edge of the water, accompanied by a local Quarry and Pumice Rd, indicating active mineral extraction at the time. The southern entry of the New River into the sea and the presence of various Pump stations and levee systems illustrate the ongoing efforts to manage water and salinity in this unique desert depression.