L.A. Takes a Fresh Look at Recycled Water

Facing dwindling freshwater supplies, the city is ready to stop dumping millions of gallons into the Pacific—and to follow Orange County’s lead.
Taste-testing water that 27 hours ago was raw sewage at the Orange County Water District's groundwater replenishment facility

Ana Venegas/SCNG via ZUMA Wire

For the past decade, Chapman University professor Chris Kim has been a regular on tours of the Groundwater Replenishment System at the Orange County Water District (OCWD).

“Basically, I take any opportunity I can come up with to bring students out to this facility,” says Kim, who teaches chemistry and geology.

As they make their way through the plant, one especially striking visual tends to stick with Kim’s students: three large metal sinks filled with water at various stages of purification. On the far right, the liquid has the dark shade of motor oil; the contents of the center sink are a yellowish brown; and finally, the liquid on the left is crystal clear. Not only does the facility churn out up to 100 million gallons of recycled wastewater each day for about 850,000 residents of the county, but it also shows some 5,000 annual guests that the water is perfectly fine to drink. (At the end of the tour, visitors are invited to taste it for themselves.)

Kim says he’s particularly impressed by the “feats of engineering and chemistry that are involved in purifying water at that scale,” as well as the quality controls in place. “When people can see for themselves the rigor with which they clean it, test it, and monitor it and how automated everything is, I think that allays a lot of fears of the abstract concept of raw sewage going in and water coming out,” he says. “You can see every stage of the process. You understand that ‘Oh, there's no way this water is anything but perfectly fine to drink.’”

The massive success of OCWD—and, not insignificantly, its welcoming public reception—has laid the groundwork for similar water conservation initiatives taking off in neighboring Los Angeles. In February, Mayor Eric Garcetti announced that the city will recycle 100 percent of its wastewater by 2035; this news came just days after Senators Robert Hertzberg and Scott Wiener introduced SB 332 to the California legislature. Sponsored by NRDC, the bill aims to reduce wastewater discharge to the Pacific Ocean by 95 percent by 2040.

City officials plan to achieve this goal by upgrading the city’s Hyperion Water Reclamation Plant near Santa Monica Bay. Liz Crosson, head of infrastructure for Mayor Garcetti, explains that the Hyperion plant currently receives 81 percent of L.A.’s wastewater, but recycles only 27 percent of that. That, Crosson says, is going to change following the $2 billion upgrade, to be completed over the next 16 years. “That’s really significant with regard to SB 332, because it is a coastal water reclamation plant,” she says. “Right now any water that is not recycled is discharged to the ocean.”

L.A. mayor Eric Garcetti at the Hyperion water treatment plant during the announcement that the city will recycle 100 percent of the city's wastewater by 2035

Eric Garcetti/Flickr

The city is piloting different technologies at Hyperion and its three other treatment plants. “We’re really in the testing phase and determining what is the most efficient and safe treatment train, as well as the most cost-effective way to get us to our goals,” Crosson says. The nearby example of Orange County, she says, proves it is possible to treat wastewater at the scale proposed by SB 332. “The technology’s out there,” she says. “It’s just refining it at this point.”

Once the plant’s upgrade is complete, officials expect that it will provide 35 percent of the L.A. water supply. Currently, the city’s four water treatment facilities together provide a scant 2 percent. Water diversions from around the region provide most of the rest. The Colorado River and the Sacramento–San Joaquin River Delta alone provide about 50 percent of the water supply for more than 19 million people living in Southern California.

This isn’t Los Angeles’s first attempt to cut its dependence on imported water. Back in 1995, the city spent $55 million on the so-called East Valley Water Recycling Project, which aimed to use treated wastewater to recharge the San Fernando Valley Aquifer and help make the city “drought proof.” The plan failed; local officials conducted little public outreach to convince residents of its worth and unveiled it just ahead of a mayoral race. When one candidate referred to the effort as “toilet to tap,” the term stuck. The city shut down the plant after just a few days of use.

Fortunately, a lot has changed in the years since. As Tracy Quinn, NRDC’s director of California water conservation and efficiency, notes, a number of factors have gotten Californians to rethink the importance of water recycling.

For one, California only recently emerged from a punishing six-year drought, one of its worst in recorded history. The first four years were the driest since recordkeeping began, in 1895. In response, then-governor Jerry Brown declared a statewide emergency in 2014, asking residents to cut their water use by 20 percent. Even now, Quinn says, more than a million Californians still don’t have access to safe drinking water. “We know that climate change is making the supplies that we’ve relied on for decades, if not over a century, unreliable,” she says. “We have to do more.”

To start with, Los Angeles can follow Orange County’s example, just as San Diego did. San Diego Mayor Kevin Faulconer toured the OCWD plant while he was a city council member and has since shepherded his city to its own water purification program, which is currently on target to produce 30 million gallons of purified water daily starting in 2023.

The OCWD began promoting treated water a full decade before its system became operational to prepare its residents for the shift, and Los Angeles must do the same. Aside from proving to Angelenos that drinking recycled water is safe, the city must also explain the economic and conservation values of recycled water.

The arguments in its favor are pretty simple, says Drevet Hunt, a senior attorney in NRDC’s Nature program. As of now, the Hyperion plant discharges about 75 percent of the water it treats—around 190 million gallons daily—into the Santa Monica Bay. “There’s a lot of money and energy spent on that treatment,” Hunt says. With additional purification, that water could simply be reused to create a local, reliable source of water. “Going one step higher doesn’t necessarily mean twice as much cost,” he adds. “It can often just be an incremental change.”

The Hyperion water treatment plant

Doc Searls/Flickr

Importing water is also costly for California’s natural resources, often reducing once-great rivers, such as the Colorado, to a trickle. “It’s really harmful to the environment, the ecology, in those rivers,” Hunt says. Water diversions have had an especially deleterious effect on salmon runs and other native fish habitat and exacerbated toxic algae blooms that have flourished in the California Delta. For those who depend on these resources, the results have been devastating: Years of droughts, coupled with demands from Central Valley agribusinesses for more water, are swiftly depleting what were once robust fisheries.

California’s water woes won’t get better on their own. Quinn points out that the Sierra snowpack, which feeds the delta and provides around a third of California’s water, is expected to diminish by 65 percent by the end of the century. Climate change has rendered the future of the Colorado River, already drubbed by a 19-year drought, uncertain. She says water agencies, including in Los Angeles, have stored water to prepare for “when water was not available to be imported here.”

Even so, “there’s only a limited capacity for storage,” Quinn notes, so “having a local supply is critical.”

Mayor Garcetti’s office is banking on the hope that Angelenos will agree. Crosson feels confident that the recent drought helped cement a new public understanding of the importance of water conservation, and with it the recognition that “this is the new normal.”

Protect Clean Water

Southeast Dispatch

As droughts parch the Southeast, interstate squabbles heat up over the Tennessee River (and the Chattahoochee . . . and the Flint . . . and the Apalachicola).

Western Dispatch

Residents of the city’s affordable housing units don’t normally get prioritized for energy efficiency upgrades. That’s about to change.


By relying on plants, soil, and natural systems to manage rainfall runoff, green infrastructure tackles urban water woes and boosts climate resilience. Here’s how.

Western Dispatch

Farms drink up a majority of the state’s water supply, but the details are murky. Most of the largest irrigation districts aren’t reporting how much water they delivered to farmers.

Western Dispatch

Photographer Max Whittaker shows us the many faces of the delta, including its strange and fascinating history and the challenges complicating its future.

Western Dispatch

Since this giant salty lake in the desert lost its water supply, its bird habitat has been shrinking and more toxic dust is wafting up from its dry lake bed. Can the Salton Sea be saved?


Ditch-diggers and cement trucks? Try trees and rainwater cisterns. City planners across the country are realizing that green infrastructure is the key to climate resilience.


Drought affects more people globally than any other natural disaster. Here’s what causes these prolonged dry spells and how we can mitigate their impact.


An NRDC lawsuit has led to the comeback of the Golden State’s second-largest river (and its salmon).

onEarth Story

The Los Angeles River—as faded and forgotten a Hollywood starlet as there ever was—could be poised for a comeback.

Western Dispatch

The state knows a thing or two about creating a climate policy that’ll keep battling carbon pollution—even if the feds cut and run.

Join Us

When you sign up you'll become a member of NRDC's Activist Network. We will keep you informed with the latest alerts and progress reports.