Los Angeles is moving forward with a water recycling project
Los Angeles will soon begin construction on a $740 million project to convert wastewater into clean drinking water in the San Fernando Valley, augmenting the city’s water supply in an effort to prepare for a worsening drought linked to climate change.
The city plans to begin construction next month on new facilities at the Donald C. Tillman Water Reclamation Plant in Van Nuys. Once completed, these facilities will treat wastewater and produce 20 million liters of drinking water per day, enough to supply about 250,000 people.
The drinking water produced by the plant will be piped 10 miles northeast to LA County’s Hansen Spreading Grounds, where it will flow into basins and tap into an underground water aquifer for storage. The Los Angeles Department of Water and Power will later pump water from the wells, and after further testing and treatment, the water will enter pipes and be delivered to taps.
“It’s a big step forward for this city,” said Jesus Gonzalez, DWP’s water resources manager. With this project, he said, the city will start using recycled water as “a new source of sustainable, drought-proof drinking water.”
LA has been recycling wastewater for decades but previously used clean water to irrigate outdoor areas such as golf courses and parks. With this new plant, which is scheduled to be completed in 2027, the city will for the first time start using recycled water as part of its drinking water supply.
Step, called LA Groundwater Replenishment Projectwas approved last month by the city’s Board of Water and Power Commissioners. LA Mayor Karen Bass and other city officials have they call it an important part of their efforts investing in local water resources and reducing dependence on growing imports being less honest about climate change.
This project has been thirty years in the making. The city built part of the infrastructure, including pipelines and pumping stations, in the 1990s, but efforts were scrapped in 2000 when a debate erupted over newspaper headlines. called the “toilet-to-tap” project.. The problem was that caught up in the mayoral campaign and a 2001 ballot measure calling for the Valley to separate from the city. The plan was then set asidedelaying it for years.
Meanwhile, Orange County moved forward with its development Groundwater Replenishment Programthe world’s largest project of its kind, now recycling 130 million liters of water per day. The system cleans the wastewater using an advanced three-step treatment process, and the water is then drilled and injected into an underground water well, where it becomes part of the supply.
“We’re going to build the same kind of treatment system that Orange County has now had for 15 years of success,” Gonzalez said.
An extensive treatment and purification process, in addition to testing, will ensure that the drinking water will be “incredibly safe once it’s released and served to our customers,” he said.
The Tillman facility is one of four wastewater treatment facilities operated by LA Sanitation and Environment.
Currently, treated effluent from the plant is discharged into the Los Angeles River in the Sepulveda Basin, which provides a significant portion of the river’s flow during dry periods. The water recycling project was designed so that as clean water is pumped out, a stream of clean wastewater will still flow to sustain the LA River and its wildlife habitat, Gonzalez said.
To help cover the cost of the new construction, the city received more than $400 million in federal and state grants and the Metropolitan Water District of Southern California.
The project has been a long time coming, said Mark Gold, director of water scarcity solutions for the Environmental Defense Council.
“This is recycled water that should have been in the city’s pipeline 20 years ago, but water politics got in the way,” Gold said. “It’s great that it’s finally happening and it will be finished soon.”
City leaders are investing in the facility and are planning a major effort to convert sewage into clean drinking water. With a project called Clean Water Los Angelesthey plan to treat recycled water from the Hyperion Water Reclamation Plant, the city’s largest wastewater treatment plant, and use that water — 230 million gallons a day — to supply about a third of LA’s drinking water.
UCLA researchers recently analyzed project plansformerly known as Operation Next, and found to significantly strengthen local water sustainability and deliver long-term economic benefits by significantly reducing the risks of water shortages.
Researchers at UCLA’s Luskin Center for Innovation examined nearly 100,000 scenarios, including shortages caused by drought or major earthquakes that could burst waterways and cut off supplies. They found themselves in their own reportsponsored by the DWP and released this week, that having Clean Water LA online will greatly increase the resilience of the city’s drinking water supply in all situations.
“Any way you cut it, our estimates are that the benefits will far outweigh the costs,” said Gregory Pierce, research director of the Luskin Center.
In recent years, Los Angeles has been importing about 90 percent of its water, drawing supplies from the Eastern Sierra, the Sacramento-San Joaquin River Delta and the Colorado River.
“Because the uncertainty of the weather will be the main cause of water shortages in the city, the city must adapt by building a reliable local supply,” said Pierce. “It’s important to make that investment even though it’s very expensive up front.”
The cost of clean water in LA has not been determined. In recent years, various initial estimates have ranged from $6 billion to $20 billion.
The DWP at the moment to fix the system describing project options. City officials said it will help move LA toward the goal of 100% recycling of city wastewater in 2035.
While most of the treated water is planned to be used to recharge groundwater basins, the DWP also plans to consider incorporating “direct potable reuse,” which involves delivering treated water directly to customers or mixing it with other materials.
Last year, the California State Water Resources Control Board adopt the country’s leading regulations which allows water utilities to begin developing facilities that put ultra-pure recycled water straight into drinking water. Gonzalez said the DWP will soon open a small demonstration center on the department’s campus near Griffith Park to develop treatment technologies and monitoring methods that ensure the protection of public health.
As the city turns to developing what could be the largest water recycling project in the nation, several questions remain to be answered, including where the treatment facilities will be located, how the water distribution system will be designed, and what the construction timeline will be. , said Gold.
“A clear roadmap and implementation plan for Pure Water LA is still lacking,” he said.
Gold said another important question is how the city’s project at the Hyperion plant in Playa Del Rey will fit with the Metropolitan Water District’s separate plan for another recycling plant in Carson, called Southern California Clean Water. According to MWD’s latest estimate, that project will cost $8 billion when fully constructed and produce 150 million gallons of water daily.
“My concern is, are we running out of time to make those decisions so that we don’t become a completely different system,” said Gold. “Because it’s very important, not only in LA but in the region, for the systems to be integrated.”
He said it is important for LA officials to make a decision quickly because the MWD project is currently at least five years away from the city’s construction.
“There are still a lot of questions, because of the urgency of making LA a climate-resilient city when it comes to water supply,” he said.
Others raise more questions about the city’s approach.
Melanie Winter, who leads a non-profit organization called the River Project and promotes environmental changes in the LA River watershed, said she is happy that the city is following the completion of the water restoration project in the San Fernando Valley, but it should also be LA. focus more on better rainwater management. He advocated removing concrete and footpaths from parts of the river to capture rainwater naturally and recharge groundwater.
“We have to have a large portion of our groundwater coming from stormwater management, from removing impervious surfaces and allowing them to flow in,” Winter said. “We have to have rainwater as a big part of that equation.”
Regarding future water recycling projects, Winter said he thinks Los Angeles should focus on developing small-scale facilities to ensure reuse, rather than planning to rely on a large centralized system that he says could be at risk of failure due to earthquakes or otherwise. accidents. He pointed out that the existing infrastructure in the Hyperion industry has a history of failures and sewage spills.
“We need to think in a more distributed way than the centralized systems that are currently being considered and proposed,” Winter said. “If you have a decentralized network, then it’s more stable. And they weren’t thinking about it the way they should be looking at it.”
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