UC Cooperative Extension helps Californians use water wisely

Research news UC Cooperative Extension helps Californians use water wisely Marie Narlock L Marin Master Gardener Jeanne Ballesttrero, right, shows client Candace Berthrong, left, how to read her water meter for water leaks, and how to use the meter to manage water usage. Ballesttrero is one of more than 100 Master Gardeners who have been trained in water conservation by the Marin Municipal Water District water district as part of the Garden Walks program. ast year was California’s driest on record, and we are now facing our third straight year of drought. Growers have fallowed fields they can’t irrigate and ranchers have sold cattle they can’t feed, driving up food costs nationwide. Cities are feeling the pinch too because Governor Jerry Brown has asked for a voluntary 20% cut in urban water use. And rivers are so low that wildlife agencies have trucked millions of juvenile salmon from hatcheries toward the ocean. To help Califor- nia adapt to drought, UC Division of Agriculture and Natural Resources (ANR) and UC Cooperative Extension (UCCE) researchers are finding ways for Californians to use less water. “This drought is unprecedented — we’ve never had such a lack of rainfall since we started keep- ing track,” says Doug Parker, who both directs UC ANR’s California Institute for Water Resources and leads the Division’s Strategic Initiative on Water Quality, Quantity and Security. Also un- precedented is the mere trickle that California farmers are getting from the state and fed- eral projects that deliver surface wa- ter to users in the Central Valley and elsewhere. That said, drought is nothing new here. “California has always had droughts and will always have droughts,” Parker says. “It’s something we need to learn to live with.” During most years, agriculture uses 80% of the state’s developed water, which doesn’t include envi- ronmental allocations. “Farmers are looking for ways they can stretch their water budget,” he says. Those who grow annual crops can simply plant fewer acres, and he estimates that about 5% of the irrigated crop- land statewide will be fallowed this year. But not every farmer has this option. Permanent crops like almonds and grapes need some water just to stay alive, so growers often turn to groundwater when supplies of surface water are cut. “This is not sustainable in the long run but is not a bad thing in the short run,” Parker says. “It’s a loan and we need to remember to pay it back.” Downsides of overpumping 56 CALIFORNIA AGRICULTURE • VOLUME 68 , NUMBER 3 groundwater range from depleting supplies to land subsidence. Urban areas typically use 20% of developed water. While cities have more water than agriculture has this year, many are still getting far less than they’re used to. It’s not as dire as it was during the last big drought in the 1970s, however, thanks to conservation measures like low-flow toilets and showerheads. “We learned our lessons,” Parker says. “We actually use less water per person now.” Water-smart gardening There’s still plenty of room for city dwellers to conserve more water. About half of the water they use statewide — nearly 200 gallons a day per household — goes to landscaping. To help gardeners use water ef- ficiently, the Marin Master Gardeners teamed up with the Marin Municipal Water District (MMWD) to offer free water audits called Garden Walks. With training from the MMWD conservation team, well over 100 Master Gardeners visit people’s gardens to evaluate and consult on plantings and irrigation systems. “One of the biggest problems is automatic irrigation systems that aren’t maintained,” says Steven Swain, UCCE environmental horticulture advisor for Marin and Sonoma counties. “Every year, we find some that are dumping hundreds of gallons a day, but the leaks are often underground so no one knew.” Another problem that’s easy to solve is outdated controllers, which, unlike modern versions, don’t shut off auto- matically when it rains. Other fixes include xeriscaping as well as gardening in zones to make sure that water- loving plants share a dedicated irrigation circuit. Now in its fifth year, the Garden Walks program saves participating households an average of 1,000 gallons annually. “We’re saving a lot of water — about 23 million gallons over the life of the program,” Swain says. The program pencils out financially too, costing ratepayers less per gallon saved than the baseline rate for a gallon used. Other municipalities are taking note. “There’s a lot interest,” Swain says. “We’ve gotten calls from other California counties and even Tacoma, Washington.” Efficient irrigation Just as some garden plants are thirsty, there’s no getting around that some crops need plenty of water. For example, avocados are shallow-rooted trees na- tive to Central and South American cloud forests and need frequent irrigations throughout the day. Another difficulty is that California avocados grow along the coast from San Diego to Santa Cruz, where water is pricey and contains salts that can affect the trees’ productivity.