LOS ANGELES — This city of nearly 4 million people imports most of its water, bringing in 80 percent of what it consumed last year.
Mayor Eric Garcetti has said that must change.
The Democrat has directed Los Angeles to shrink its water use 20 percent in two years and cut imports in half within a decade. Water leaders now are looking at a range of options to meet those mandates, including enhanced ways to capture stormwater, repairing a contaminated reservoir and even turning wastewater into drinkable water.
"Water provides economic growth, quality of life, sustainability," Adel Hagekhalil, assistant director of the Los Angeles Bureau of Sanitation, said this week at the VerdeXchange conference here. "We don’t have an infinite amount of water, so we have to find ways to capture and reuse water.
"We have to start thinking about it," he added. "It’s not something that’s going to be there forever."
Los Angles boomed in the early 20th century in large part after early water leaders used money and some subterfuge to gain the city the right to water from the Owens Valley, east of the Sierra Nevada. An aqueduct was built to funnel those supplies. The city’s goal a century later is to become more water independent. The Bureau of Sanitation is crafting a "One Water Los Angeles 2040 Plan."
Los Angeles’ commitment to develop more local water is important as the state enters its fourth year of drought, said Felicia Marcus,
chairwoman of the state Water Resources Control Board.
"We’re spending time delivering water to small communities who are running out of water," Marcus said. "If we had a large community running out of water, there’s just no way."
Los Angeles, she added, "can be a model for the nation. It’s the second largest city in the country, so it’s undeniably important."
The Los Angeles Department of Water and Power (LADWP) is finishing a stormwater master plan that will guide how it handles rain going forward. The blueprint is aimed at evaluating existing stormwater capture facilities and projects and developing alternatives, the agency said. It’s expected to be finished in mid-2015. A future goal is to capture 85 percent of the rain that falls, Hagekhalil said.
LADWP, along with the city’s Department of Public Works, Bureau of Sanitation and Bureau of Engineering in 2012, published a recycled water plan. It urged a focus on local sources.
Los Angeles gets much of its imported water from Northern California and the Colorado River, as well as the city-owned aqueduct. But there are battles over those supplies. In Northern California, local fisheries and some residents are competing with farmers who need more water for thirsty crops. And California is one of seven states relying on the Colorado River, where demand outpaces supplies. Depending on water from those places is a risk, the recycled-water plan says.
"Future water supplies from distant sources are becoming more restricted and less reliable," it says. "Environmental commitments, periods of dry years, low snowpack, and judicial decisions have all contributed towards significant cuts in imported supplies."
While some long-term planning was already underway, Garcetti’s directive in October gave a new impetus, said Nancy Sutley, LADWP’s chief sustainability and economic development officer and the former director of the White House Council on Environmental Quality.
"He’s accelerated the time frame of the existing plans," Sutley said. "He’s also put a premium on city agencies working together. It’s very helpful to have the mayor pushing."
LADWP has made conservation a priority. Through outreach to residents, the agency said, it’s been able to keep demand relatively flat from the 1970s, even as the city’s population has grown.
The agency offers incentives to cut water use, including a program that pays residents $3.50 per square foot to rip out their water-dependent lawns and put in sustainable replacements. It’s a program popular in many cities, but Los Angeles’ payment is among the highest (Greenwire, July 2, 2014).
With the drought, however, and the need to secure more local supplies, water planning has become more urgent.
"Believe me, you’re not going to get there one lawn at a time," said Mark Gold, acting director of the UCLA Institute for the Environment and Sustainability. "It’s going to have to be much bolder."
Climate change also presents challenges, said Marty Adams, LADWP’s water systems manager. It’s expected that precipitation in the future will fall more as water than snow. The snowpack in the state’s northern Sierra Nevada typically has provided water in the spring and summer as it melted, but that snowpack over the last three years of drought has been well below average levels.
"Things will not be as they have been historically," Adams said. When it rains, he said, "we’re going to have to do a much better job of capturing water right away and putting it somewhere we can use it in the future."
At the same time, he said, there are questions about how much to invest in the Sacramento-San Joaquin River Delta. That’s one source of water that’s sent south to places like Los Angeles.
"The one thing that is known is we cannot build solutions overnight," Adams said. "We are needing those things now. One of the challenges is how to invest in things we already have in place" and also in future projects.
Protection from earthquakes also is an issue, he said. LADWP’s aqueduct crosses the San Andreas Fault, known for triggering massive quakes.
"This is one of the critical resources for the future," Adams said of the aqueduct. "We cannot stop using it now as we plan for the future."
Recycled water’s PR problem
Some of the local water plans are immediately on the horizon, including stormwater capture projects, Sutley said. Others are longer-term efforts like treating a contaminated groundwater basin in the San Fernando Valley, which currently is a Superfund site. The goal is to get it online so it can store recycled water by 2021.
"We have groundwater pumping rights. We can store stormwater that we capture," Sutley said. "We can store highly treated recycled water."
The city already has a series of "purple pipes" that deliver recycled water for irrigation purposes. There’s talk of expanding the Bureau of Sanitation site in El Segundo — near Los Angeles International Airport — so that it can handle more volume.
Still under consideration is turning wastewater into drinking water.
"I think that everybody believes that the real opportunity lies in being able to really reuse that water as part of the potable water system," Sutley said.
There are two options for treating wastewater: indirect potable use and direct potable use. With indirect, wastewater goes through a treatment plant for purification. After that, it’s pumped into the ground as an "environmental buffer," before it’s pulled out again, sent back to a treatment plant, and then can be used as drinking water, said Guillaume Clairet, executive vice president at H20 Innovations, which sells wastewater treatment systems.
But Clairet said Los Angeles could save money by choosing direct potable use. In that process, the "return to nature" step is skipped and the wastewater is purified and made available for consumption.
Regulatory approval typically is needed, he said, and there’s the obstacle of public acceptance. But the water in the direct potable process is consistently monitored to make sure it meets water quality standards, he said.
"So why do we have to spend the money to pump it down into the ground, pump it back up, go to an expensive water treatment facility" because society is not yet ready to drink it, he said.