California is a force of nature when it comes to almonds. The state’s farmers produce virtually the entire US almond crop and dominate the international market. As the market has grown, almonds have become California’s largest single crop—now accounting for about 12% of irrigated acreage, with more than 1.2 million acres harvested in 2016. Availability of water is clearly a major issue for the industry, since the trees must be irrigated throughout the long spring and summer dry season. At a May event on water issues organized by the Almond Board of California, I was asked for some thoughts on the water realities almond growers must grapple with in coming years. Here are three key takeaways.

• Growers in the San Joaquin Valley must address a long-term groundwater deficit. More than 80% of almond acreage is in the San Joaquin Valley (see map). Decades of unchecked pumping in the valley have resulted in a chronic groundwater deficit averaging nearly 2 million acre-feet per year—equivalent to about two Folsom reservoirs. Groundwater sustainability agencies must now devise plans to comply with the state’s 2014 groundwater law by bringing their water supply and use into balance over the next two decades. This means both augmenting supplies and reducing water use. Almond growers—along with others—need to be engaged in this process.
• Augmenting local supplies can fill some of the gap––and almond growers can help. Up to a quarter of the San Joaquin Valley’s groundwater deficit could be eliminated by replenishing aquifers during high-flow events and wet winters like 2017. Spreading water on farmland is a cost-effective way to capture this water. Almond orchards are good candidates for such a process, given the suitability of much of the land for recharge (see map). Moreover, almond trees are dormant in winter and early spring, when extra water is most often available. Pilot projects and groundwater-recharge research are helping establish best practices and addressing ongoing questions among growers about the impact of winter flooding on almond crops. Almond growers also need to support other types of groundwater banking projects—such as recharge basins—that can help maximize available water supplies.
• Managing demand will also be essential for reaching sustainability. Water use will need to fall to reduce the groundwater deficit. While this will pose some challenges, the good news is that farmers have been managing water demand for decades in this water-scarce region. Since the early 1980s, irrigated crop acreage in the San Joaquin Valley has hovered around 5 million acres, while the value of valley agriculture has roughly doubled (in today’s dollars). Farmers have responded to water scarcity by investing in crops and practices that generate more dollars per drop. The expansion of crops like almonds—and the corresponding decline in cotton and other field crops that bring in less revenue—reflects this shift. During the recent drought, farmers also used tools such as water trading and selective fallowing of less-productive lands. These same tools can help smooth the transition to balanced groundwater use, given the willingness of  water users who benefit most from using scarce supplies—for instance, those who need to keep orchards thriving during droughts—to compensate others who can use less.

Almonds are expected to remain a top crop in the state, and a leading source of farm revenues, for decades to come. But water stress will be an increasingly important factor for California’s almond growers and for the San Joaquin Valley more generally. The farm sector’s water challenges can’t be addressed farm by farm, or crop by crop. Cooperative approaches—including trading and groundwater recharge—will be essential to a smooth landing for the valley’s almond industry and the regional economy overall.