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Issue link: http://wateronline.epubxp.com/i/694011
back to water restrictions and unplanted crops in the state. Worse, climate models predict wider swings in weather, with the potential for bigger storms and drier droughts. That's a huge threat in an agricultural basin that is the envy of the world for its combination of great weather, great soils, and great irrigation infrastructure. Ironically, many farmers reacted to previous droughts by adopting more precise irrigation technologies, including drip and microsprinklers. To get a return on their investment in these expensive systems, they shifted from annual crops like cotton or melons to permanent crops like wine grapes, almonds, and fruit trees. The downside: In a drought like the most recent one, it's possible to take a one-year economic hit and just not plant cotton or melons, but it's a devastating blow to consider drying up an orchard just part-way into its productive life — maybe before it has even produced an economic return. Water-savvy farmers were faced with a kind of Sophie's Choice: kill their crops (and maybe destroy their entire business) or pump groundwater to eke by. Meanwhile, a whole generation of urban residents had already installed low- flow showerheads, low-use toilets, and xeriscapes, making it tougher to squeeze much more conservation from municipal water districts. Of course, water issues in California go well beyond supply. Environmental issues like smog and greenhouse gas emissions are linked to agricultural water. Addressing environmental needs — an ongoing tug-of-war between farmers and fish — is a massive challenge that demands attention not just to maintaining river flows and reservoir levels, but also to safeguarding water quality. Meanwhile, Western water law discourages conservation and, often, even measurement of withdrawals. On the plus side, nurturing the soil ecosystem, which is key to productivity and sustainability, is directly tied to water. California farmers need top-shelf agricultural water technology. They should be getting it from the inventors and innovators that have made the state famous for generations. Instead, Israel and Singapore, among others, have emerged as the Silicon Valleys of Water. It's ironic. Alternative Water Sources The first key shift California needs to make is located directly between the ears — not in a technological, innovation- challenge sort of way, but in a change of mindset. While farmers and planners look to the hills to seek places to site new reservoirs for water capture (and environmentalists draw lines in the sand at every turn), the state must look at alternative water sources that are already right under their noses. Throughout farm country, lagoons at dairy farms, wastewater ponds beside every vegetable processing plant, and municipal wastewater treatment aeration tanks represent millions of gallons of available water. That wastewater has already been pumped to the surface or conveyed to the site. It's already been counted out of river flows or groundwater reserves. Rather than seeking even more water from the environment — while releasing wastewater back to the ecosystem — it makes more sense to treat effluent for reuse as irrigation water. There's plenty of precedent. Israel, by far the world leader in water reuse, sends 90 percent of its wastewater to treatment plants; of that, a staggering 85.6 percent is reused. Think about that. For every gallon of water that comes through an Israeli tap, more than three quarts is reused. More than half of the desert nation's irrigation water is treated, recycled wastewater. Even better, a study by the Galilee Technology Center demonstrated that irrigation with treated wastewater eliminated the need to flush fields with additional water to reduce soil salinity — which is also an issue in many areas of the Central Valley. Emerging Technologies There are some bright spots on the horizon. The California State University and University of California systems have scores of dedicated researchers committed to improving water efficiency. Their efforts range from breeding more water- efficient crops and improving irrigation timing — the demand side of the equation — to advancing water delivery systems on the supply side. Some especially exciting technologies focus at the intersection of our understanding of irrigation management and our growing awareness of the complexities of soil biochemistry. California farmers need top-shelf agricultural water technology. They should be getting it from the inventors and innovators that have made the state famous for generations. The San Joaquin River, dried in long stretches by diversions and drought, epito- mizes the challenges facing California. 38 wateronline.com n Water Innovations WATERSUPPLY&MANAGEMENT;