Treated wastewater – long used to water golf courses and green spaces throughout the East Valley – could be reaching taps in kitchens across the state after the governor’s office passed rules that will allow communities to recycle reclaimed water into drinking water.
Reclaimed water, also called effluent, is highly treated wastewater, according to the Arizona Department of Environmental Quality.
The Governor’s Regulatory Review Council approved new administrative rules on Oct. 3 that will allow appropriate facilities to process reclaimed water for drinking water, also known as direct potable reuse, said Trevor Baggiore, ADEQ Water Quality Division manager.
The new rules go into effect on Jan. 1, 2018. ADEQ has two workgroups that will continue to craft additional standards to be implemented at a later date.
There are five classes of reclaimed water in Arizona’s quality standards, ranging from Class C to Class A+.
The rules will allow only facilities producing Class A+ or B+ reclaimed water to pursue direct potable reuse. The rules also will require additional treatments in order for water to reach federal drinking water quality standards.
Any facility that pursues direct potable reuse of reclaimed water also will have to conduct a pilot project that proves it can meet appropriate standards, Baggiore said.
All reclaimed water plants operated by Mesa, Chandler and Gilbert produce Class A+ effluent, the highest class of reclaimed water in Arizona, according to the state’s reclaimed water quality standards.
This is not the first time reclaimed drinking water has made headlines in Arizona.
Over the summer, the AZ Pure Water Brew Challenge pitted brewers across the state against each other to see who could brew the best beer from purified recycled wastewater. The goal of the campaign was to inform Arizonans about water-use issues and the technologies that exist to purify wastewater.
Gilbert’s Arizona Wilderness Brewing Company came in second place in the competition with its Pure Water Double IPA.
Regionally, San Diego is leading the way in the direct potable reuse of reclaimed water. Through the city’s Pure Water San Diego Program, it plans to use treated recycled effluent to supply one-third of the city’s drinking water by 2035.
San Diego chose this route over expanding its use of treated ocean water from the nearby Claude Lewis Carlsbad Desalination Plant because treating reclaimed water proved more cost-effective.
Direct potable reuse also had a lesser greenhouse gas effect than desalination, said Sarah Porter, director at the Kyl Center for Water Policy at ASU’s Morrison Institute for Public Policy.
ADEQ does not anticipate that it will receive applications to begin recycling reclaimed water for drinking water in the near future because municipalities will need time to develop the technologies and processes necessary to meet drinking water standards.
“(ADEQ has) not specified the technology (facilities will use) because we want to be innovative, but we do require the (water quality) specifications,” Baggiore said.
“In the short term, I don’t think there will be huge uptake (in applications for direct potable reuse), but in the long term there definitely will be,” she said.
Mesa, Chandler and Gilbert all have extensive reclaimed water programs that currently offset drinking water use for non-potable uses by using treated effluent to irrigate golf courses, homeowner association landscaping and other green spaces.
All three cities also use reclaimed water to recharge the water table.
Mesa and Tempe are also co-owners of the 91st Avenue Water Reclamation Plant along with Phoenix and four other municipalities.
That facility is operated by Phoenix and provides reclaimed water for a variety of uses, including cooling at Palo Verde Nuclear Generating Station.
Chandler, which has meticulously forecast its water use for decades, is unlikely to take advantage of reclaimed water for potable uses. That is because the city already has planned out where its water will come from through its eventual build-out.
“We have done a lot of preparation in the past into how to effectively use our water,” said Christopher Connor, Chandler Utility Regulatory Affairs manager.
The city already uses 100 percent of its effluent for non-potable needs, which allows the Chandler to reserve more of its potable water for drinking.
However, the city still will look at whether direct potable reuse is a viable option in the future.
“As it becomes a hotter topic, we will look at it if it would be a cost-saving topic versus (our current plans),” Connor said.
Gilbert also uses 100 percent of the town’s effluent for non-potable needs. The town has 70 miles of reclaimed water pipelines that deliver to over 50 users. Roughly 40 percent of the town’s effluent is used for turf irrigation.
The remaining 60 percent of reclaimed water in the town is used to recharge groundwater through basins like the Riparian Preserve at Water Ranch. This not only helps increase groundwater supplies but also allows the town to claim credits that can be exchanged to acquire drinking water from other sources, Gilbert wastewater manager Mark Horn said.
Gilbert does not currently have plans to divert reclaimed water resources from those current uses toward direct potable reuse, though that could change in the future as public perception shifts.
“There is a possibility in the future that as the policy changes and the public perception of potable reuse changes we could pursues it, but there are no plans right now,” Gilbert Water Resources manager Eric Braun said. “We still need to catch up from a public perception standpoint.”
Whether communities choose to move forward with direct potable reuse of reclaimed water, the increased flexibility ultimately will benefit all communities across the state as they navigate the complex water issues that go hand in hand with living in the desert.
“(This rule) benefits every community because it gives them one more water management tool,” Porter said. “Whether they use it or not, they benefit from it.”
Currently, reclaimed water accounts for only 3 percent of the state’s overall use.
The flexibility that increased usage provides could be necessary as communities around the state grapple with water use issues.
The Colorado River provides 40 percent of the state’s water supply, and Lake Mead – the reservoir that holds Colorado River water for Arizona, Nevada and California – is only 34 percent full after being 94 percent full in 2000, according to the report.
– Reach Wayne Schutsky at 480-898-6533 or firstname.lastname@example.org.