Breathing Hazard: Air Pollution in the Salton Sea Region

The Salton Sea, California’s largest lake, has shrunk by more than 70 square miles (19%) in the past 30 years. Colorado River water irrigates more than half a million acres of productive farmland in the Imperial and Coachella valleys, in southeastern California (Figure ES-1). Runoff from these fields sustains the lake but has decreased by almost 20% since the 1990s (Figure ES-2) as a result of agreements transferring water out of the region. Continuing efforts to protect Lake Mead and Lake Powell have incentivized farmers to further reduce their use of Colorado River water, accelerating the decline of the Salton Sea and exposing additional lakebed (known as “playa”). More playa means more dust in an area already suffering from bad air quality and some of the highest respiratory hospitalization rates in the state. Expected additional water use reductions will accelerate the Salton Sea’s decline and increase the amount of playa exposed, affecting the health of the 560,000 people in the region.