The Los Angeles Times ran an article today describing the impacts of groundwater pumping on agriculture in California’s Central Valley (link). High rates of groundwater use have caused ground levels to subside by as much as a foot a year, and have also lowered water tables, forcing farmers to pay high prices to pump water from deeper levels. This is using up water from aquifers which has been in place for as much as 20,000 years and which cannot be readily replenished. Experts say that eventually this may force farmers to abandon as much as a million acres due to the lack of readily available water supplies.
What crops are produced in this area? Marshall Shepherd, UGA atmospheric sciences professor, provided this set of maps describing the crops that grow in this region. Some of the biggest increase has been in the production of nuts, which use a lot of water and cannot be fallowed during droughts without destroying the trees. Grist posted an interesting article this morning about how the national demand for almonds and other nuts have changed the face of agriculture in California in recent years.
This week California and Washington both announced initiatives to help protect the remaining groundwater. Yahoo News has stories on California’s new regulations and Washington’s declaration of a drought emergency by their governor, due to a snow pack which is only 7 percent of normal.