Lower Colorado River Valley Lower Colorado River Valley The Lower Colorado River Valley ("LCRV") is the river region of the lower Colorado River of the southwestern United States in North America that rises in the Rocky Mountains and has its outlet at the Colorado River Delta in the northern Gulf of California in northwestern Mexico, between the states of Baja California and Sonora. This north–south stretch of the Colorado River forms the border between the U.S. states of California/Arizona and Nevada/Arizona, and between the Mexican states of Baja California/Sonora. It is commonly defined as the region from below Hoover Dam and Lake Mead to
Course of the Colorado River of this water is used for irrigation in the Mexicali Valley, one of Mexico's most fertile agricultural regions. Below the Morelos Dam the Colorado forms the international border for a short distance, between Baja California and Arizona, before reaching the Southern International Boundary at San Luis Rio Colorado, where it crosses entirely into Mexico. For the remainder of its course to the Gulf, the river forms the boundary between Baja California (west) and Sonora (east). "River", however, is a misnomer as the Colorado is dry or small stream most of the year, due to its flow being almost completely exhausted