What to know before California votes to approve “toilet-to-tap” projects

In only a few years, some Californians may have to flush down their toilets to access a future source of drinking water, provided that the much-anticipated “toilet-to-tap” laws are approved next week.

Tuesday’s groundbreaking proposal to expedite “direct potable reuse” (DPR), which allows treated wastewater to be released directly into a public water system or just upstream from a treatment facility, will be discussed by the California State Water Resources Control Board.

According to Darrin Polhemus, deputy director of the board’s drinking water division, “it’s a real important step for just adding to the portfolio that we can use here in the West,” he told The Hill.

He clarified that these skills might improve California’s water resilience, offer several environmental advantages, and lessen the need for long-distance water transportation.

Polhemus declared, “We’re not using it once and throwing it in the ocean.”

Although these rules would be a significant step forward for the state’s water recycling program, utilities in California are not new to using sewage for other purposes.

They have been using “indirect potable reuse” for years, which involves injecting treated wastewater into lakes, rivers, or groundwater aquifers as environmental buffers before releasing it into a municipal system.

Having handled sewage in some form or another since the 1970s, Orange County today possesses the largest indirect potable reuse water purification system in the world. As of right now, the county says it is recovering all of its wastewater.

DPR, on the other hand, doesn’t require the usage of an environmental storage barrier or an underground aquifer, in contrast to indirect potable reuse.

DPR systems won’t start appearing overnight, even if the board does pass the regulations on Tuesday. And even when they do, wastewater won’t actually be flowing straight from a toilet to a tap.

The state’s Office of Administrative Law would first need to approve the regulations, which Polhemus said would happen by the summer or fall of the following year. Utilities could then start working on these massive, intricate projects, the majority of which would take six or seven years to finish, he claimed.

Therefore, Polhemus continued, “no one will be drinking direct potable reuse in the near future.”

repeatedly utilizing a system that already exists

Although California frequently leads the country in environmental legislation and regulation, the Golden State was not the first to establish DPR regulations.

After upgrading its drinking water requirements in January, Colorado approved DPR regulations; however, as of yet, no utilities are using these restrictions. Texas released case-by-case regulatory advice for DPR, while Florida and Arizona are now developing corresponding regulations.

On the other hand, it is anticipated that California’s laws would be the most stringent and that they will cater to a number of commercial projects that are currently in the development stages.

The 2017 A.B. 574 bill, which required the water resources board to create “uniform water recycling criteria for direct potable reuse” by December 31, 2023, at the latest, is the source of the proposed regulations.

The laws stipulate that all source water for DPR projects must originate from municipal sewage and prohibit the construction of bypasses as a means of evading required treatment procedures.

The 69-page proposal includes comprehensive directions for plant operations, maintenance, and compliance in addition to guidance for managing and monitoring chemicals and pathogens.

A statement of reasons released by the board in July lists the provision of a safe, dependable, and drought-proof drinking water supply in addition to a simplified approval process for DPR facilities as anticipated benefits of the proposed regulations.

Polhemus pointed out that from an economic perspective, DPR would allow utilities to forgo some of the costly and disruptive pipeline and infrastructure building that is associated with other kinds of water recycling initiatives.

“This opportunity to access the existing potable water distribution system is provided by DPR,” he stated.

While acknowledging that DPR is pricey, Polhemus emphasized that it is significantly less expensive than desalination. Cities in California face “phenomenally high” expenses for dams and aqueducts even if they manage to create new natural water sources, he continued.

Getting the public on board

Regulators in California have had a difficult time bringing directly recycled wastewater into practice, despite the technology’s many potential advantages.

For instance, San Diego began a campaign to install DPR in the 1990s, but KPBS reported that the plans were shelved after the misnomer “toilet to tap” gained traction and started to influence public opinion.

Since the San Diego fiasco, public perception of DPR has changed as the science has become more conclusive and the state of California’s water shortage has gotten worse. After several decades of drought, Jennifer West, managing director of the nonprofit organization WateReuse California, said she thinks Californians are starting to appreciate DPR more.

“We can do better than that — using water once and discharging it,” she stated to The Hill.

Californians, according to West, have undergone a change in “the collective consciousness,” with citizens increasingly complaining when their communities don’t recover enough wastewater.

Polhemus also credited the growing public acceptability to the fact that water recycling has been going on for a while, at least in an indirect capacity.

He continued, calling DPR “the final step,” saying, “For decades, we’ve learned from all of the activities we’ve done for recycling — from irrigation to indirect potable reuse.”

According to Polhemus, if the regulations are passed, they will also mandate public consultation before the building of any DPR facilities.

“We would like to involve the public in the decision-making process by bringing them along and explaining the situation,” he stated.

Polhemus restated that the board is only giving utilities a framework if they so chose to build a plant, emphasizing that “we’re not imposing this on anybody.”

A persistent concern pertaining to the possible existence of chemicals and infectious diseases in wastewater has been noted by him and others as a deterrent to public acceptance.

Polhemus emphasized, nonetheless, that in order to guarantee the removal of biological pollutants, the proposed laws incorporated “triple redundancy.”

According to the July statement of reasons, researchers used the parasites Giardia and Cryptosporidium as well as norovirus, which is the most frequent cause of acute gastroenteritis, to determine an appropriate pathogen threshold and treatment regimen.

According to the document, they came to the conclusion that controlling the amount of bacteria was not necessary because treating “the hardier pathogen types” could “easily deal with the bacteria threat.”

West went on, “The water will be the cleanest around, and the regulations are very protective of public health.”

Regarding the chemical aspect, Polhemus promoted a potent blend of granulated activated carbon, enhanced oxidation, and reverse osmosis.

He argued that regulators have “the confidence that we’ll be able to treat for things we don’t even know are there” because of this redundancy.

Wastewater will always be produced in a community

Many projects in Southern California are ready to start a multi-year planning and construction process if the DPR standards are officially approved.

One of these initiatives is Pure Water San Diego, a multi-phase plan that, by the end of 2035, aims to supply over half of San Diego’s water from regional sources.

According to the designs, Pure Water San Diego’s initial phase would employ a reservoir for indirect potable reuse, but the city is thinking of integrating DPR into the project’s second phase.

Meanwhile, as part of a two-phased project called Pure Water Southern California, the Metropolitan Water District of Southern California is collaborating with the Los Angeles County Sanitation Districts and intends to include DPR right away.

Indirect potable use and a kind of DPR known as “raw water augmentation,” in which treated wastewater is combined with imported Colorado River water and state resources, are anticipated to be included in the first phase.

Because the mixture would enter a drinking water treatment plant straight and then be distributed to customers, instead of first passing through an environmental buffer, this method is still considered DPR.

“By 2032, we hope to have Pure Water Southern California operational and utilizing DPR,” Metropolitan Water District press office manager Rebecca Kimitch stated to The Hill.

Project officials stated that they have not yet determined whether the DPR technology will use another approach or raw water augmentation in the second phase.

DPR is essential to both California’s overall water management strategy and our Pure Water Southern California program, according to Kimitch.

“However, DPR will permit us to immediately integrate this stream of filtered water into our system, irrespective of the natural conditions,” she continued.

According to Kimitch, Southern California has been depending on importing water from the Colorado River and the state’s northern regions as the region lacks natural resources to slake the thirst of its citizens.

She then added, “We just want to use it as much as we can.” “It is not being as efficient and sustainable as we can be if we use it once and then dump it into the ocean.”

Many of these opinions were mirrored by Polhemus, who said that include DPR in utility portfolios just “makes a lot of sense” as they think about ways to increase their resilience in the face of drought.

Wastewater will always be produced in a community, he claimed.