Drip irrigation provides the salinity control needed for profitable irrigation of tomatoes in the San Joaquin Valley

• Published in: California agriculture (Berkeley, Calif.) Vol. 63; no. 3; pp. 131 - 136
• Main Authors: Blaine Hanson, Don E. May, Jirka Simnek, Jan Hopmans, Robert Hutmacher
• Format: Journal Article
• Language: English
• Published: University of California Agriculture and Natural Resources 01-07-2009
• ISSN: 0008-0845; 2160-8091
• DOI: 10.3733/ca.v063n03p131

Despite nearly 30 years of research supporting the need for subsurface drainage-water disposal facilities, the lack of these facilities continues to plague agriculture on the San Joaquin Valley's west side. One option for coping with the resulting soil salinity and shallow water-table problems is to convert from furrow or sprinkle irrigation to drip irrigation. Commercial field studies showed that subsurface drip systems can be highly profitable for growing processing tomatoes in the San Joaquin Valley, provided that the leaching fraction can achieve adequate salinity control in the root zone. Computer simulations of water and salt movement showed localized leaching fractions of about 25% under subsurface drip irrigation, when water applications equaled the potential crop evapotranspiration. This research suggests that subsurface drip irrigation can be successfully used in commercial fields without increasing root-zone soil salinity, potentially eliminating the need for subsurface drainage-water disposal facilities.