No, Almonds Don’t Use 10% of California’s Water


Almond Board of California continues to respond to inaccurate information in the media about growing almonds. This is done through letters to the editor, direct follow-up with reporters and journalists, comment section postings and more. Proactive media outreach includes desk-side briefings, orchard tours, pitching positive story ideas and expert interviews. Below is an excerpt from a response to a myth that originated in a Slate article and has since spread to other media. This response was originally posted on the ABC blog.  

Do almonds use 10% of California’s total water supply? The short answer is no.

This myth, which we’ve heard a few times in the media, seems to trace back to a Slate article from last May. Its author generally engages in a thoughtful and nuanced discussion of California’s water use. He notes that almonds are an important economic contributor in the state, and that all foods require water, including some that are far more water-intensive than almonds.

Unfortunately, in the months since the original post, others have ignored those parts of the Slate article while repeating this one claim, which doesn’t, shall we say, “hold water.”

Slate Article Claim

Here’s what the author says:          

California as a whole diverts or pumps 43 million acre-feet of water each year to supplement its meager rainfall. In total, agriculture consumes 34 million acre-feet of that. (An acre-foot is just what it sounds like: the amount of water needed to cover an acre of flat ground up to a foot, or about 325,000 gallons of water.) In 2013, there were 940,000 acres of almonds in California, according to the USDA. Each acre of almonds uses 3 to 4 acre-feet of water each year. … Almonds alone use about 10 percent of California’s total water supply each year. …

Recalcuating Almond Water Use

Water requirements vary by tree age and some other factors, but to give Slate the benefit of the doubt, let’s use the high end. That would be 4 acre-feet/acre x 940,000 acres = 3.76 million acre-feet. That’s an overestimate (keep in mind that more than 100,000 of those acres are not mature trees, so they require far less water), and it’s still not 10% of 43 million acre-feet.

But that’s just the tip of the iceberg when it comes to the problems with this calculation.

First: Forty-three million acre-feet of water is not California’s “total water supply.” In fact, from 2001 to 2010 (the most recent data available from the Department of Water Resources), the state’s total managed water supply averaged more than 80 million acre-feet.1 California’s managed water supply is divided among three sectors: urban, agricultural and environmental uses. Generally speaking, environmental use — things like managing wetlands and protecting various species of fish — is the largest of the three. That water is managed by humans — including through pumping and diversion — much like urban and agricultural water. According to the Public Policy Institute of California2, environmental use represents about 50% of the state’s total supply on average. But it’s left out of the author’s calculations completely. Accounting for environmental water as about half of the state’s total supply turns “less than 9%” into “less than 4.5%.”

Second: There’s no question that California is in the midst of a historic drought, but that doesn’t mean we should ignore the role of rainfall altogether. According to grower information collected through the California Almond Sustainability Program3, rainfall accounts for about one-quarter of almond tree water needs, on average, across the state. That means, in a normal year, the actual amount of California’s water that goes to almonds is closer to 3%. The exact number, of course, varies a bit from year to year, but you can clearly see that the 10% many have claimed is simply false.

It’s also worth noting that California farmers have steadily done more with less. In the past 40 years, the value of California agriculture has increased by more than 85%; during that period, the total California crop-applied water use fell by more than 5%.4 Even though the acreage of perennial crops in California, including almonds, increased during the 2000s, the total amount of managed water that went to farms held steady — so a shift in crops grown hasn’t meant more total water going to agriculture.1

Be a part of the conversation. Consider writing a letter to the editor; share your story with the media through the Good Neighbor program; give a presentation to a local civic organization through the newly formed Speakers Bureau; share almond-growing facts on social media. Contact Carissa Sauer to get involved with these groups, or to access key messages, fact sheets and resources.


1. California Department of Water Resources. California Water Plan, Update 2013. Volume 1, Chapter 3. October 2014.
2. Public Policy Institute of California. Just the Facts: Water Use In California. July 2014.
3. California Almond Sustainability Program, 2014.
4. California Department of Water Resources. California Water Plan, Update 2013. Volume 3, Chapter 2. October 2014.