Impacts of California Water Supply on Agriculture

The State of California is among the most productive farming regions in the world.  Rich soils and a Mediterranean Climate enable California farmers to produce more than 400 crops that literally feed the nation and large parts of the world.  Data from the California Department of Food & Agriculture (CDFA) indicate the state’s farmers produce more than one-third of the fresh vegetables and more than two-thirds of the fresh fruits and nuts consumed in the United States.  According to CDFA, in 2019, the last year before the global COVID-19 global pandemic, the value of California’s agricultural international exports exceeded $21.7 billion.

All this bounty depends on an adequate supply of water for irrigation.  Historically, water supplies for irrigated agriculture were not an issue.  Two major water projects, the Central Valley Project (CVP), which is operated by the United States Bureau of Reclamation (Reclamation), and the State Water Project (SWP), which is operated by the California Department of Water Resources (DWR), as well as local water projects operated by numerous irrigation districts, were able to meet the demands of farmers throughout the state.  The CVP and SWP, which capture runoff from the Cascade and Sierra Nevada Mountains and transport that water to distant regions of the state, were able to adequately supply irrigation water to nearly 4 million acres of farmland.  By itself, the CVP, has the capacity to meet the demands of approximately one-third of the agricultural land in California.

Much has recently been written about the “aridification” of the west.  It is beyond reasonable dispute that climate change is affecting water supply.[1]  However, as depicted in the bar chart below, California has had, at least since at least 1906, a history of varying hydrology.

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[1] In California, the "water year" is defined as the period from October 1 of one year through September 30 of the following year.  Based on long-term precipitation data, each Water Year is classified as: critical, dry, below normal, above normal, or wet.

 

Over the last three decades, the ability of the CVP and SWP to meet the demands of irrigated agriculture has diminished not because of a reduction in supply. Rather, the capability of the CVP and SWP, as well as other water project, to deliver water has been reduced primarily due to restrictions imposed on their operations for the ostensible protection of at-risk native fish species. 

The CVP is a case in point.  Reclamation developed the CVP to ensure it had capability to deliver sufficient water on an annual basis even if there were a severe, multi-year drought – Reclamation assumed a repeat of the extended 1928 through 1934 drought, which remains one of the worst droughts on record in the Sacramento River watershed.  And, prior to the implementation of federal and state environmental laws beginning in the early 1990s, the CVP was, in fact, able to make full deliveries even during dry or critical years.  The only exception was in 1977, the driest year on record, when Reclamation provided CVO agricultural contractors with a 25% allocation.  Yet, because of restrictions imposed on operations of the CVP under the federal Endangered Species Act, the federal Clean Water Act, the federal Central Valley Project Improvement Act, and the state Porter-Cologne Water Quality Act, even in a wet years like 2019, the CVP is unable to make full allocations.  In 2019, the allocation for many agricultural contractors was 75%.  In an average year, like 2010, the allocation to agricultural contractors was only 45%. In 2020, the allocation for CVP agricultural contractors was 20%, which is remarkable because although 2020 was dry, 2019 was an exceptionally wet and ended with storage in CVP reservoirs near capacity.  In exceptionally dry years, like 2014, 2015, 2021, and 2022, the allocation was zero.  These more recent allocations lead to the inescapable conclusion that the CVP is broken.

 

As a consequence of policy decisions to reallocate water from historic uses, primarily from irrigation to the environment, today the single largest user of CVP water is the environment.  This does not mean that the environmental use of water is bad public policy or that water should be supplied without regard to the impact of CVP and SWP operations on the environment, but it is disingenuous to assert that California lacks the water resources required to serve both the needs of people, including the irrigation needs of farmers to produce food, and the environment.  Undoubtedly, the water shortages currently being experienced by the state’s farmers, as well as urban users, are a consequence of climate change and hydrology; but the shortages and their impacts could have been mitigated or avoided if decisions regarding how water are managed were more considerate of the impact of the reallocation of water on irrigated agriculture and if actions had been taken to improve the existing and construct new water supply infrastructure.

In May 1957, DWR issued Bulletin No. 3, the California Water Plan.  In the foreword of that publication, DWR observed:

California is presently faced with problems of a highly critical nature—the need for further control, protection, conservation, and distribution of her most vital resource—water. While these problems are not new, having been existent ever since the advent of the first white settlers, never before have they reached such widespread and serious proportions.  Their critical nature stems not only from the unprecedented recent growth of population, industry, and agriculture in a semiarid state, but also from the consequences of a long period during which the construction of water conservation works has not kept pace with increased need for additional water.  Unless correct action is taken—and taken immediately—the consequences may be disastrous.

Bulletin No. 3 ultimately led to the approval and construction of the SWP.  What the existing drought should make clear is that history is repeating itself; unless correct action is taken, and taken immediately, the consequences may be disastrous.

California League Of Food Producers