Los Angeles plans to put recycled water in your faucet
Water has always been recycled. The water molecules in your shower or your cup of coffee could be the same molecules that rained down on dinosaurs over 65 million years ago.
However, with advances in water recycling technology, the water that went down your sink this morning could be back in your tap sooner than you think.
The City of Los Angeles and agencies in Southern California are studying what’s called “direct potable reuse,” which means putting purified recycled water back directly into our drinking water systems. This differs from indirect potable reuse, where water spends time in a substantial environmental barrier such as an underground aquifer or in a reservoir.
Water recycling experts shudder at the infamous phrase “toilet on tap,” an alliteration that became popular with politicians and headlines in the late 1990s, when projects to use recycled water for groundwater replenishment was beginning to take shape in the valley and town of San Gabriel. from Los Angeles.
Miller Brewing Co. and community groups vigorously opposed the San Gabriel Valley project, even suing the agencies involved for the environmental impact reports.
Today, recurring cycles of devastating drought as well as advances in science have softened this view.
For memory :
10:21 a.m. on July 22, 2022An earlier version of this article omitted the first name of Brad Coffey from the Metropolitan Water District of Southern California.
“There was a public health legacy where sanitary engineering practices and regulators viewed wastewater as waste, it was something to be avoided, something to be feared,” said Brad Coffey of the Metropolitan Water District. of Southern California. “Now that we have the technology…the public, the regulators, the scientific community have much more confidence in our ability to safely reuse this water supply.”
Their efforts hinge on the State Water Resources Control Board, which has been tasked by lawmakers with developing a uniform set of regulations on the direct reuse of drinking water by December 31, 2023.
The city of Los Angeles is wasting no time in preparing projects that can be launched once the regulations are adopted.
A direct drinking water reuse demonstration facility near Headworks Reservoir, just north of Griffith Park, will likely be the first state-approved direct drinking water reuse project, said Jesus Gonzalez, head of the water recycling policy at the Los Angeles Department of Water and Power. It will take advantage of recycled water produced by a facility in Glendale, but the water will not yet be added to the potable water system. However, it will serve as a proof of concept, he said.
“It will be the future of Los Angeles water, the future of the state’s water supply,” Gonzalez said.
The Headworks project is expected to go live soon after the regulations come into place — tentatively within the next five years, Gonzalez said.
But the Headworks project is just one part of the city’s ambitious plan to recycle 100% of its wastewater by 2035 – a promise made by Mayor Eric Garcetti several years ago.
To accomplish this, Hyperion’s water reclamation plant – which currently treats wastewater only to the level needed to discharge it into Santa Monica Bay – is to be converted into an advanced water purification facility that produces water clean enough to drink.
The Department of Water and Energy plans to take the water produced by Hyperion – enough for 2 million people – and put it into vast aquifers under the southern part of Los Angeles County as well as in the valley. of San Fernando.
There are also plans to implement direct drinking water reuse at the Los Angeles Aqueduct Filtration Plant in the San Fernando Valley, which currently cleans water siphoned from the Owens Valley and from the Mono Lake basin to the north.
The city is also working with the Water Replenishment District, which manages groundwater rights in the area, on a master plan to determine optimal locations for injecting recycled water into aquifers.
This massive undertaking, dubbed Operation Next, comes at an equally large price tag – more than $16 billion for the entire program, which is expected to be completed in 2058.
An advanced small-scale purification facility is already nearing completion, built in partnership with Los Angeles International Airport to produce 1.5 million gallons per day of water for non-potable uses such as toilet flushing and restroom cooling, according to Traci Minamide, COO of LA Sanitation and Environment. The project will go live in the spring of 2023 and is seen as another proof of concept for the larger Operation Hyperion.
City officials are scrambling to find sources of funding to allow Hyperion 2035 and Operation Next to move forward as planned.
“We knocked on every door, state and federal, trying to get grants or loans,” Gonzalez said.
Another advanced water purification project at the Donald C. Tillman Water Reclamation Plant in Van Nuys, which will send water spilling into groundwater basins in the San Fernando Valley, is expected to be completed in December 2026.
However, as the city pushes ahead with its ambitious plans, some have questioned its ability to properly maintain its existing water infrastructure.
Just a year ago, Hyperion’s factory suffered a catastrophic flood that spilled 17 million gallons of untreated sewage into the ocean. The failure also resulted in the diversion of millions of gallons of drinking water to uses normally served by recycled water, and residents of El Segundo sued the city for alleged exposure to toxic pollutants as a result. of the spill, according to court documents.
The plant is now fully operational again and water quality is normal, Minamide said, and diversions and emergency storage are being built in case of future incidents.
“This spill has reinforced everyone, including us, that we need monitors and alarms upstream of the sewage treatment plant to be able to identify any issues, whether they are spills or infrastructure issues,” Gonzalez said.
In the meantime, the State Water Board must consider these incidents when developing new regulations and determine how the regulations would hold up in the worst case.
“The key to what we’re trying to do is always to protect public health, so when we’re writing these regulations, we’re focused on protecting public health,” said Randy Barnard, technical operations section chief at the drinking water division of the water board. the water.
Since it is not yet possible to monitor pathogens and chemicals in real time, water treatment operators must rely on the concept of “log eliminations”, which measures the number of contaminants removed from the water at each stage of the process, rather than the number contaminants remaining in the water.
Three log removals are equivalent to removing 99.9% of the contaminant, for example. The state requires up to 20 log deletions for some viruses.
“We are sometimes accused of being too conservative, but that’s because public health is at risk,” Barnard said.
The state water board has already shown draft regulations to a panel of experts who made a preliminary finding that they sufficiently protect public health — a critical step in the process. Once officially approved, they will go through an administrative and legal process that will take about a year before being officially adopted.
Water industry leaders are eager to get to work.
“The technology is so good,” said Shane Trussell, president and CEO of Trussell Tech, which is involved in advanced water purification projects in Los Angeles, San Diego and other cities.
Once regulations are in place and big agencies launch projects, Trussell thinks smaller agencies will follow.
“I expect that by 2040 … most Southern California effluent will be recycled or on track to be recycled,” Trussell said.