Title: Irrigation Issues in the San Joaquin Valley: Evapotranspiration, Soil Salinity, and Water Quality

Author: Jody Lowes

Abstract:

The nature of the San Joaquin Valley, California is both a blessing and a curse for agriculture in the region. The soils are rich and good for growing but the availability is not sufficient for the crops that are being grown there. In comparing evapotranspiration rates of crops during the year to the availability of water, there is an inverse relationship. When water availability is low, water need for the crops is high. This dependency on irrigation in such a dry place as the San Joaquin Valley creates a problem with salinization of the soil and harm to the crops. To combat soil salinity, over-irrigation and artificial drainage are instituted. The San Luis Drain is an example of this drainage “fix.” The San Luis Drain flows directly to the Kesterson National Wildlife Refuge and has ultimately created a pooling area for harmful agricultural runoff and other toxins, specifically selenium. These pollutants disrupt the ecology of this system and lead to deformities and mortality in some waterfowl and fish.

Key References:

Banhgoo, M. et al. (1994). Effect of soil salinity and irrigation levels on kenaf production in the San Joaquin Valley, California. California Agricultural Technology Institute. Retrieved April 29, 2006, from http://cati.csufresno.edu/ip/rese/94/940102/

Cech, Thomas, (2005). Principles of Water Resources. Hoboken, NJ: John Wiley & Sons Inc.

Lara, D. et al. (2003). San Joaquin Valley drainage monitoring program. Dept. of Water Resources.

Van Schilfgraarde, J. et al. (1989). Irrigation-induced water quality problems. Washington D.C.: National Academy Press.

Return to Water Resources Papers page.

---

Date: May 2006
Student: jlowes@willamette.edu
ENVR 327: Water Resources
Instructor: Dr. Karen Arabas
http://www.willamette.edu/~karabas/courses/envr327w