In the face of megadroughts, LA is transforming how it uses water

After the Metropolitan Water District of Southern California told 6 million residents on Wednesday that they can water their lawns only once a week, the district’s general manager declared it a wake-up call: “The amount of water we have available to us right now,” he said at a press conference, “is not going to be enough to carry us through the entire year unless we do something different.”

There’s a chance that the current megadrought in the Western US (the worst drought in the region in 1,200 years) might last until 2030. And climate change is making severe droughts in the area even more likely in the future. As a result, cities like LA are undergoing redesign initiatives—including lawn-free landscaping, streets that can better capture stormwater, and new water recycling technology—to deal with shortages in ways that go beyond the temporary new restrictions.

“will keep experiencing long drought, LA worsened by climate change,” says Peter Gleick, senior fellow and past president at the nonprofit Pacific Institute “It is not only necessary for LA, and all of California, to adapt to these changes, but it is possible.”

Rethinking laws is an obvious first step; around half of the water used in urban areas ends up on outdoor ornamental landscaping. “We don’t need these green carpets of lawn that take up the lion’s share of that water,” says Felicia Marcus, the former board president of LA’s Department of Public Works and former chair of the California State Water Resources Control Board, who is now a visiting fellow at Stanford University. “There’s an enormous amount of water that we’re spending not just on lawns but on keeping those lawns a certain shade of green during the summer—anytime in the summer, let alone in what may be the worst drought in modern history.”

LA County runs a “cash for grass” program that gives residents a rebate for replacing grass with drought-tolerant plants, which has already eliminated more than 2 million square feet of turf. But it could go further, and local governments might eventually decide to ban “nonfunctional grass,” following the example of Las Vegas, where lawns are now banned for decoration at offices or in medians. In the area managed by the Metropolitan Water District of Southern California, a total ban on watering lawns may be introduced by the fall, though there are currently no proposals to ban lawsns themselves.

California cities can also save water by plugging leaks in pipelines and homes. Inside, switching to more efficient washing machines, showers, dishwashers, and other equipment can help reduce water use; along with reducing outdoor watering and fixing leaks, a recent Pacific Institute report estimates that such measures could allow cities to cut water use by 30% to 48%.

Los Angeles already uses less water than it did 20 years ago, despite having more than a million new residents, because of more efficient appliances. And technology keeps improving. (One shower available in Europe, for example, filters water as it falls so that it can be reused in a loopcutting use by 90%.)

Bigger changes can happen in urban infrastructure. Climate change is also making more extreme rainfall when it happens, and variable: In December, Los Angeles got 9.6 inches of rain. In January, February, and March, it typically wet months in the region, it got almost no rain. When the rain fell in December, an estimated 29.5 billion gallons flowed down the LA River—a concrete channel—and landed in the ocean instead of in groundwater that could later be used. LA County is now planning major projects that could eventually capture as much as 98 billion gallons of water per year. Another water recycling project in the area will add more capacity.

Some changes are simple, like cutting openings in curbs that can let rainwater flow from streets into gardens instead of into storm drains. Permeable pavement on parking lots or sidewalks can let water seep underground. In parks, large underground tanks can capture rain that can later be used to irrigate trees.

Some of the changes have been happening at a small scale for years, including an entire neighborhood that was retrofitted to capture stormwater in 2010. But new funding from a tax passed in 2018 is providing hundreds of millions of dollars a year to help it happen more broadly across the city. Because of the lengthy planning process—including a commitment from agencies to equity as it rolls out new infrastructure—the complete transformation will take decades.

The area is also planning to make a major shift to recycled water. Hyperion, a sewage treatment plant near the beach next to Los Angeles International Airport, currently treats wastewater and then dumps it into the ocean. But new technology being installed at the plant will filter and treat the water so that it’s clean enough to send into groundwater instead, for eventual reuse. By 2035, the project expects to produce more than 200 million gallons of water per day, enough to meet nearly a third of LA’s water demand. Local water authorities are also beginning to work to clean up contaminated groundwater, a process that is expensive but now worth doing in the face of extreme water shortages.

Eventually, the area may also use desalination plants that process ocean water into drinking water, though the technology still has challenges.

“Right now [desalination is] Neither environmentally nor economically good enough to do, and I think we should do other things first,” says Gregory Pierce, an urban planning professor and director of the Human Right to Water Solutions Lab at UCLA’s Luskin Center for Innovation. The process is very energy-intensive and creates concentrated brine that can be harmful to marine life when it’s added back into the ocean.

At some point, though it’s very controversial, the state may also rethink how water is used by agriculture, Pierce says. Some 80% of the state’s water goes to farming, not cities, and arguably some of the produce grown in California’s Central Valley might make more sense to grow in regions that get more rain (or, potentially, in indoor vertical farms that use 90% less water than traditional field farms).

The local plans for recycling and stormwater capture mark a shift away from the area’s reliance on water from outside sources, from an aqueduct built in 1905 to siphon water from the Owens Valley—in a ruthless process that inspired the plot of the 1974 film Chinatown—to another aqueduct that pulls water through the desert from the Colorado River, and a massive third system, built in the 1960s, that pumps water from Northern California over the mountains.

“The bottom line is the potential for LA to really live more within its water means is tremendous, but we need to do a lot,” Marcus says, “and we need to do it even faster than we’re doing it right now. That way, we’re on the way.”

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