The decline of the Salton Sea’s size, water quality and habitat will reach a tipping point after 2017, when mitigation flows to the Salton Sea cease and the local impacts of the largest agriculture-to-urban water conservation and transfer program rapidly materialize.

The mitigation deliveries were initiated to address the effect of a series of agreements signed in 2003 (known as the Quantification Settlement Agreement, or QSA). These agreements, signed by the Imperial Irrigation District, the Coachella Valley Water District, the Metropolitan Water District, the San Diego County Water Authority, the U.S. Department of Interior and California state agencies, served to quantify and limit California’s draw on the Colorado River to 4.4 million acre-feet per year.

tipping_imageThe linchpin of the QSA is the largest agricultural-to-urban water transfer in the nation’s history: approximately 400,000 acre-feet per year of conserved water from Imperial Valley farms to urban water agencies, primarily in the San Diego region. To date, the conserved water flowing to San Diego has been generated primarily through a land fallowing program, allowing IID to continue delivering water to the Sea in amounts equal to historic farm-field runoff.

On January 1, 2018, the fallowing program for mitigation water to the Salton Sea will end. By order of the State Water Resources Control Board, water conservation through fallowing will be replaced with system-wide and on-farm efficiency measures that will reduce the total amount of water used to irrigate farmland. Starting in 2018, approximately 200,000 acre-feet per year of inflows to the Sea will cease as a result of these conservation measures. By 2026, the reduction of water inflows will total 300,000 acre-feet per year.

As the Sea dries up, it will expose more than 50,000 acres of lakebed made up of fine-grain soil particles that contain farm-field sediments, including salts, fertilizers and pesticides. Winds in Imperial and Riverside counties moving across the “playa” will cause fine dust and toxins to become airborne, posing a significant threat to public health, agriculture and the local economy.

Already, Imperial County is deemed a “non-attainment” area for air quality by the U.S. Environmental Protection Agency, with childhood hospitalizations for childhood asthma at nearly three times the statewide average. Air quality in Riverside County consistently ranks among the worst in the nation.

It was understood when the QSA was signed that it would accelerate the Sea’s decline, which is why the agreement included a commitment to finance mitigation and, ultimately, restoration of the Sea. The water agencies agreed to finance up to $133 million to mitigate transfer impacts, with the State of California committing to plan for and finance any mitigation costs above that amount. As for restoration, that obligation was to have been entirely borne by the state.

To date, various state and local plans have been developed and some habitat conservation projects have begun, however, no comprehensive restoration plan has been implemented or funded in the decade since the QSA was signed.