The Past and Future of California Groundwater

Artist Mark Clark’s rendition of California in 1851.

Just a little more than two generations ago, you could take a boat from Bakersfield to Stockton. During
this trip, you would have passed Alpaugh Island while travelling through Tulare Lake, which was the largest freshwater lake west of the Mississippi at the time. In the early 20th century, Tulare Lake was drained to feed California’s irrigation projects and sustain a booming population and agricultural
development. Since then, California’s population has grown from around 100,000 to nearly 40 million, and agricultural production has grown from around 2 million acres to nearly 30 million.

California’s foundation in agriculture was established on bountiful sources of freshwater and their replenishment through a reliable Sierra snowpack. Things have changed. Our current water storage and delivery system was developed to sustain 20 million less people than currently reside in California, and it doesn’t have a chance at keeping up with agriculture. As a result, California famers have begun supplementing surface water with groundwater, and during a drought, there are consequences when supplementing becomes replacing. In a normal year, groundwater accounts for about 40% of the water supply, and during drought, it has increased to about 75%. This has significantly impacted our groundwater reserves and water quality. Land subsidence (the drop in elevation due to groundwater pumping) has historically occurred at about a foot per year, and it is likely to accelerate with the increase in new wells being installed. As we drill more and deeper to find new groundwater, a few other things happen: salt concentrations, energy costs and water treatment expenses all increase significantly, while crop yields continue to decline.

In response to these issues, California passed a $7.5 billion dollar water bond, one-third of which will be
allocated to surface water development. Following this measure, California enacted the Sustainable Groundwater Management Act in early 2015. The act is the first law in California history designed to manage groundwater resources. However, it will be some time before farmers begin to feel the impact of this new legislation. Initial steps mandate that local groundwater sustainability agencies be formed by mid-2017. Once formed, these agencies will also be tasked with “correcting overdraft conditions by 2040.”

Farmers will likely face more water regulations over the next twenty-five years as this new legislation is
implemented. Staying informed of new developments is the best way to plan for future changes that impact your operation.  There are excellent sources of information within your own community such as local water coalitions. Success in California agriculture is contingent on the community using history to predict the future, staying informed, making our voices heard and adapting.

- Chad Lessard, Southern California Agronomist