UC Delivers

CIMIS conserves water and increases water availability for urban users

The Issue

The Colorado River is the only source of irrigation and drinking water in the Imperial Valley and the main source in Mexicali, Mexico. As much as 4.5 million acre-feet of Colorado River water is used every year to irrigate more than 500,000 acres in the Imperial Valley and in the Mexicali Valley, Mexico. Growers in Southern California are under continuous pressure to conserve water and transfer some of the agricultural water to urban regions of the state. The current water transfer agreement between the Imperial Irrigation District and the San Diego County Water Authority calls for transfer of up to 200,000 acre-feet annually of Imperial Valley-Colorado River water. Increased irrigation efficiency using CIMIS-based irrigation scheduling techniques and other water conservation practices is needed to supply the water demand in Southern California and northern Baja California.

What Has ANR Done?

UCCE initiated and coordinated meetings between scientists from California Department of Water Resources, University of Baja California, and the state of Baja California to install and calibrate two CIMIS weather stations in the Mexicali Valley. UC scientists developed bilingual computer programs and publications that are used to educate growers in the region about how they can improve water use efficiency and increase the availability of Colorado River water to urban areas in Southern California and northern Baja California.

The Payoff

Mexicali Valley CIMIS weather station and bilingual information cut water use

The additional weather stations and irrigation scheduling programs help growers in both Baja California and Southern California conserve water. Growers in California extensively use evapotranspiration information from CIMIS. Parker et al. (California Agriculture journal, 2000) estimated that California growers save approximately $64.7 million per year in water and energy savings by using CIMIS. The estimated benefit to growers in our region is $6.5 million in water and energy savings. In addition to water savings, reduction in agricultural water use also reduces fertilizer usage and surface and ground water pollution. In light of this data, our best management practices to conserve water and improve irrigation efficiency were included in Regional Water Quality Control Board - Region 7 Silt/Sedimentation TMDL standards.

Contact

Richard L. Snyder,(530) 752-4628, rlsnyder@ucdavis.edu

Khaled M. Bali,(760)352-9474, kmbali@ucdavis.edu