Arizona's drought turns 30 this year. 'Toilet to tap' may be one way to help ease the water crisis

By Nate Engle
Published: Wednesday, March 6, 2024 - 3:05pm
Updated: Wednesday, March 6, 2024 - 3:33pm

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wastewater plant
Lauren Gilger/KJZZ
Every day 130 million gallons of wastewater is sent from Valley city's sewer systems to the Phoenix wastewater treatment plant.

People born in 1994 will be turning 30 this year — and so will the drought in Arizona.

Groundwater is the primary source of water for the state, along with allotments from the Colorado River. But due to a population that has nearly doubled since the drought began in 1994, groundwater is drying up. In response, Gov. Katie Hobbs put a moratorium on new housing developments last year unless developers can prove they have safe access to non-groundwater sources for 100 years before they can begin construction.

Along with efforts to encourage home water use reduction, another solution being considered is a bit greener: direct potable reuse (DPR), known colloquially as "toilet to tap."

But the issue is far more complex than a catchy tagline.

Recycled water has been used in Arizona and other states for years, though not for drinking water. This "non-potable" water is used in things like toilets and irrigation systems, not intended for human ingestion.

Building by building recycling

One company in San Francisco is advocating for a new way of thinking around recycled water. Epic Cleantec CEO Aaron Tartakovsky believes that "water is, in many ways, the next frontier of recycling."

His company specializes in the process of water treatment and recycling on a more granular scale than that of municipal water treatment plants — building by building.

Epic Cleantec also recycles more than the water — its filtration system allows it to transform some of the solid waste into a soil amendment rather than the standard practice of sending it to a landfill, where it would continue to release carbon dioxide and methane. From there, the water goes through ultra-thin membranes that filter out more contaminants. The water then goes through a disinfection process to purify it before being sent back through the pipes.

"By the time the water goes through all these series of advanced filtration and treatment steps and disinfection, it is going to be identical in appearance, in smell and even in taste to what would be coming out of your tap," Tartakovsky said.

Recycling water this way leads to a significant reduction in water usage; this is the reason recycled water is already in use in some of Arizona's non-potable water sources, like irrigation.

Tartakovsky says that if buildings were to recycle their water rather than "flush and forget," it could cover up to 95% of the building's water needs.

Rebranding the term 'wastewater'

Taking that sanitation one step further results in drinkable water that can even be brewed into beer, as several local breweries have already been doing in partnership with Scottsdale Water - and as Epic Cleantec did last year in order to promote the benefits of recycled water.

Scottsdale Water also ran tests on the water from their DPR system and compared it to bottled water. In many cases, the purified water had fewer contaminants.

Scottsdale Water is the only facility in Arizona currently authorized for DPR, but that could change as the Arizona Department of Environmental Quality looks to expand water sustainability.

Brewing beer using recycled water is just one of the ways Tartakovsky says public opinion can be changed. Another is by rebranding the term "wastewater."

"So we're basically taking this whole notion of wastewater and turning it on its head and showing people that the waste and wastewater isn't really waste at all. That it is clean water, it is soil products, it is renewable energy. All of these things that we can capture in the building and then reuse," he said.

Changing regulations

24th Street Water Treatment Plant in Phoenix
Tim Agne/KJZZ
Treated water in sedimentation basins at the 24th Street Water Treatment Plant in Phoenix

The biggest hurdle to mass adoption of recycled water, outside of dismantling the "yuck" factor, is changing water regulations to adapt to modern technology. And the first way to do that is to bring the idea to legislators.

"So if we want people to care about these issues, we want people to raise these issues with their local, state and federal elected officials. They need to know about it," Tartakovsky said, adding that it's the reason his company takes such a public-facing approach.

Regulations are one of the biggest challenges facing DPR for good reason: public health. 

"When you're dealing with water, you're dealing with public health implications, which means you don't have as much tolerance to get things wrong," Tartakovsky said.

ADEQ is looking at expanding their plans for recycled water to DPR, citing the drought and an increase in water scarcity as the population continues to grow.

"I think when it comes to water recycling, I like to say this is sort of the early days of a water reuse revolution taking place. And I think places like California and Arizona are going to be the epicenter of where those movements take off," Tartakovsky said.

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