1990 Map of South of Somerton

About this map

San Luis Rio Colorado straddles the international boundary in this 1990 survey, marking the transition from the arid Yuma Desert into the northern reaches of the Desierto de Altar. The map illustrates a landscape shaped by binational agricultural and infrastructure projects, featuring the expansive irrigation networks of the Distrito de Riego Numero Catorce and an Aqueduct system. On the American side, the isolated Yuma Medium Security Facility (State Prison) stands near a series of sewage disposal ponds, reflecting the logistical needs of this border corridor. Sparse 4wd trails crisscross the desert floor, leading to scattered features like a Sub Station, a small cemetery, and the settlement of Las Adelitas just south of the border. This map provides a clear view of the borderlands during a period of steady growth and infrastructure development.