Despite Drought Relief, California's Water Footprint Remains High

Alfalfa fields under irrigation in central California.

What a difference a winter makes for California's dire drought situation. Just last year, waterways had slowed to a trickle and reservoirs were near historic lows. A couple of years ago there was almost no snowpack in the Sierras, which accounts for 30 percent of California's water. But the winter of 2016-17 was another story entirely, with record-setting "Pineapple Express" precipitation that filled reservoirs with rain and piled snow atop the Sierra Nevada mountains.

As it stands now, snowpack has accumulated to more than 144 percent of the April average and reservoirs have risen to levels not seen in many years. There was such a torrent of rain that flooding was the main concern as places in northern California like San Jose were inundated by swollen rivers. All this water is a welcome change for the California drought, and everyone from community residents to farmers to state water managers are wondering if the emergency drought regulations will remain in place. These rules have largely been successful in curbing water waste and encouraging more efficient water use throughout all sectors.

Rain: Easy Come, Easy Go?

Of course, just as quickly as the rain came, it can also go, particularly as California's climate is projected to be both warmer and drier. This means that water awareness must be part of daily life and that Californians should continue their water consciousness to make sure the supply stretches to meet demand. But state water use is immense and touches on almost all aspect of social, economic, human and environmental health. Water footprints are one good way to measure water consumption comprehensively, which was done in the 2012 report, California's Water Footprint, by the Pacific Institute, a water and environmental think tank.

Overall, the Pacific Institute states that:

Our assessment finds that California's total water footprint is about 64 million acre-feet per year, or 20 trillion gallons of water per year, which is more than double the annual average combined flows of the state's two largest rivers, the Sacramento and San Joaquin Rivers. California's water footprint is a function of its consumption of goods and has an internal and an external component. The internal water footprint is the water required to make the goods that are produced and consumed within California, as well as the direct use of water inside the state. The external water footprint includes the water required to make goods that are imported from other places and then consumed in California.

When it's broken down on a per person level, the average water footprint (WF) is 1,500 gallons of water per person per day (not including the grey, or pollution, WF). Looking closely at where the majority of the water goes, over 90 percent of California's WF is related to food and agricultural products, with meat and dairy products holding the biggest WFs based on the large amount of both rainwater and irrigated water needed to produce animal feed. The rest of the WF is consumed directly by households, mainly for lawn and garden watering, and for other industrial products like clothing, consumer products and electronics.

Leading on the Water Footprint of Food

Since California is the leading agricultural state in terms of revenue and production for fruits, vegetables, nuts and dairy, what happens in the Golden State matters for the rest of the country. Interestingly, because the state is so dry it irrigates more (also called blue WF) than much of the rest of the country, which means it depends less on rainfall (green WF) for production and more on water withdrawals that increase competition between farmers, ranchers, cities and the environment. Without a doubt, farmers and ranchers have found ways to become more efficient and productive with more limited water supplies by deploying better irrigation systems and switching crops, among other conservation practices. Despite the state's major restrictions and cuts in water deliveries over the last few years, it has buffered its water deficits by importing virtual water through the import of often less valuable goods (everything from grain to socks) and by pumping groundwater from the Central Valley aquifer system in that extremely fertile agricultural hub.

California is golden not just because of its beautiful land and perfect sunsets, but also because the state has developed a water conservation ethic, even if it tends to wax and wane.

While importing goods and becoming more productive with the water available is key, the drought has also laid bare the over-exploitation of the Central Valley aquifer system, an area that encompasses about one-sixth of the country's irrigated land and around one-fifth of the groundwater that it pumps. This matters tremendously, as over-pumping leads to water wells running dry and the state literally sinking lower because of subsidence. It takes years to replenish these aquifers, not one wet winter. Groundwater levels remain historically low despite the water riches on the surface.

Because where California leads, the rest of the US often follows, we depend on the state to show us the best way forward on water use. For instance, if the state and its people can lower their water footprint, especially when it comes to food and agriculture, we will all benefit. If state farmers can figure out ways to reduce irrigation and make the most productive use of what little rainfall they have available at any given time, that could point the rest of the US towards more productive ends. On the consumer side, of course it's important to water lawns, flush less, buy water-friendly appliances and fix leaks, but water use goes far beyond these direct uses. Peoples' choices about what they eat can make a collectively significant impact on their state's water resources.

California is golden not just because of its beautiful land and perfect sunsets, but also because the state has developed a water conservation ethic, even if it tends to wax and wane. When it comes to water, our most precious resource, instilling a conscientious mindset and set of behaviors is the least we can do.


Image "Alfalfa fields under irrigation" by Ken Figlioli on Flickr used under a Creative Commons Attribution-ShareAlike 2.0 Generic license.