Colorado to reuse water for drinking, create new supplies

CASTLE ROCK, Colorado (AP) – When Eric Seufert brewed an experimental batch of beer in 2017 with water from recycled wastewater, he wasn’t worried about the outcome. The engineering company who contacted him about testing explained the process, and together they sipped samples of the recycled water. Seufert soon realized that it was not much different from the way water is usually handled.

He said, “Every stream and river in this country has someone who enters the sewage after it has been treated.”

After tapping and tasting the barrel, the owner of 105 West Brewing Co. In Castle Rock, Colorado proudly in its own bar.

Brewing beer, cooking food and refilling water bottles with recycled sewage can become a regular practice in a state synonymous with melting snow and mountain springs.

Last week, the Colorado Water Quality Agency gave unanimous preliminary approval to regulate direct drinking water reuse — the process of treating wastewater and sending it directly to taps without first being dispersed into a larger body of water. Pending a final vote in November, the state will become the first to adopt direct regulations for potable water reuse, according to WateReuse, a national group that advocates for the method.

“Having well-developed regulations … helps ensure that projects are safe and that project backers know what is required of them,” said Laura Belanger, a water resources engineer with the nonprofit Western Resource Advocates.

With the state’s population exploding and regional water supplies dwindling, recycling water for drinking is an important opportunity to extend a limited supply, said Kevin Reedy, a conservation specialist with the Colorado Water Conservation Council. It’s a game-changer for a place like Castle Rock, he said, a city of 75,000 residents south of Denver that lies under a notable pout of the same name, and relies primarily on limited groundwater pumping for drinking.

“I think it’s an important long-term tool because it gives water providers options to respond to the scarcity of water supplies in the future, whether caused by drought or other causes,” said Mark Marlowe, Director of Castle Rock Water.

The facility already reuses about 14% of its wastewater, sends it to a stream from the treatment plant, and recycles it further downstream. But as climate change leads to more arid conditions in the western United States, the creek’s flow is becoming less reliable.

With dry bedding, the water is “lost” to the floor instead of being recovered and returned to the taps. Marlowe said mixing heavily treated wastewater directly into the facility would eliminate this climate risk.

The process, which typically requires disinfecting wastewater with ozone or ultraviolet light to remove viruses and bacteria, then filtering it through microscopic membranes to remove solids and track pollutants, is gaining interest as communities struggle with extended droughts. While many US states do not explicitly prohibit this type of water reuse, developing statewide standards could encourage rapid adoption, said Reddy of the Colorado Conservation Council.

There are no specific federal regulations for the direct reuse of drinking water. However, projects must comply with federal health standards for drinking water.

Like many Colorado cities, Castle Rock is still assessing the cost and urgency of adopting direct drinking water reuse, but plans to start testing next year so they are ready to move quickly if needed. However, it may take three to five years before the new source is available.

This is actually a short timeline for developing a new water supply, Reddy said, much faster than building a reservoir over 20 to 30 years. “You’re looking at the long-term view.”

The interest is widely shared among other cities in the Colorado Front Range, many of which are involved in the rule-making process. The area expects rapid population growth over the next few decades, and treating drinking sewage is how that growth will be met, said Greg Baker of Aurora Water.

“It’s getting more and more difficult to get new water,” Baker said. “The more we can make use of the water we already have, the better for all of us.”

Treated wastewater from local rivers and streams often must be returned to the source for downstream users, who owe minimal flows as required by various laws. But imports, such as the waters of the Colorado River pumped through the Continental Divide down to the Front Range, can in many cases be completely exhausted.

Almost all of the water in the Aurora can be reused. Currently, the city reuses about 10%, is filtered through the bank of the South Platte River, and is well positioned to accommodate future growth by expanding recycling, Baker said.

Florida, California Arizona is moving quickly to adopt the regulations as well, and few other states have started the process or have projects in place. As conditions continue to deteriorate on the Colorado River, Arizona faces forced deep water cuts, While the pressure rises For California to give up more of its stake – a strong incentive to find ways to expand what they have.

Denver and Colorado Springs—the state’s most populous cities—already recycle the majority of their water through downstream exchanges with other cities and for non-potable uses, such as watering gardens. Both expect the water to one day be recycled for drinking purposes, but officials worry that their reusable supply from the strained Colorado River may soon face mandatory cuts.

“If you build a large direct drinking reuse system and you haven’t even had it for a few years, that causes some problems,” said Greg Fisher, director of demand planning at Denver Water.

“If we are dependent on these reusable supplies (drinking water) to meet the needs of our customers, our ability to meet their needs is at risk,” Fisher said.

Water recycling projects can come with a high price, although federal funding is available. The Environmental Protection Agency provides low-cost loans for water infrastructure projects, including recycling. Through the US Bureau of Reclamation’s water recycling programs, the bipartisan Infrastructure Act provides more than $1 billion over the next five years for non-federal water recycling projects.

As part of the program, $20 million was recently awarded to the El Paso Water Board to help build a direct drinking water reuse facility. The project is expected to provide 13,000 acres of water annually – enough to supply about 26,000 families.

Not all projects will meet the requirements for federal assistance, so costs may fall on users. But delaying reuse and relying on new water – if it is available – can be costly.

“You have to compare it to the cost of new supplies and where you are going to store that,” Reddy said.

Seufert already knows he can make good beer from recycled water. He is more concerned about lowering the cost of work.

“I am concerned that the resources will be available for the planned growth in an affordable way for this region,” Seuvert said. “But, so far, I trust they are working on it.”


Follow Peterson on Twitter: @BrittanyKPeters


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