California’s thirstiest crops are under scrutiny amid the state’s severe drought. At the center of the debate are permanent crops, like almonds, that require year-round watering.
With agriculture responsible for roughly 80 percent of California’s water use, many question the practicality of crops that cannot be fallowed and the viability of producing food for export.
A crop’s water footprint—all the water needed to grow and process it—is one way of measuring its water efficiency. Almonds, in particular, have been criticized for their high water footprint, since they are one of California’s most water-intensive crops.
Around two-thirds of almonds are exported, making them the state’s leading export crop. Some critics disapprove of California sending so much virtual water to other countries in the form of food and animal feed irrigated with that water. Others have defended the growing of highly nutritious crops like almonds, noting their calorie and protein content is worth the amount of water use.
So how do California’s top export crops actually stack up when you factor nutrition into the water efficiency equation?
To answer this question, this graphic analyzes California’s top export crops as determined by the University of California, Davis. Water footprints for each crop were gathered from the Water Footprint Network, and nutrition data were obtained from the U.S. Department of Agriculture.
The intention is to compare each crop’s relative efficiency at turning water into edible material, calories, and protein. (Other important nutrients, such as vitamins, minerals, fatty acids, and antioxidants, were not considered for this ranking.)