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Boulder and Avery Brewing Partner on Wastewater Treatment

A beer byproduct from Avery Brewing is benefiting the City of Boulder’s wastewater treatment efforts

On the one hand, you have beer – arguably one of Boulder’s best-loved products – enjoyed at restaurants and homes across town. On the other hand, you have wastewater treatment, which isn’t exactly dinner-table conversation.

But what happens when the two come together?

Here in Boulder, this unlikely pairing is helping to protect the environment, preserve drinking water and reduce greenhouse gas emissions.

Avery Brewing supplies the city’s 75th Street Wastewater Treatment Facility with weak wort, a sugarwater byproduct of brewing beer. The facility, in turn, uses it to lower nitrogen levels in discharges that flow from the plant.

The combination works well because weak wort has a high level of biodegradable carbon, which feeds the microorganisms that reduce nitrogen compounds. These compounds are of significant concern to our community and to state and federal officials who worry about the ecological and health effects.

Too much nitrogen can endanger aquatic wildlife and impact drinking water quality downstream. Illness, such as “blue baby syndrome,” occurs when infants consume water high in nitrate, one form of nitrogen. The nitrate diminishes the ability of hemoglobin in red blood cells to carry oxygen throughout the body. Babies with this syndrome often have a bluish tone to their skin and are at risk for asphyxiation.

These concerns have led to strict U.S. Environmental Protection Agency and health department regulations.

Boulder has monitored and reduced nitrate discharge levels since 2007, when the city took a proactive step of removing approximately 50 percent of nitrogen from its wastewater discharges, prior to any government mandates. In 2013, the city sought and received more than $1 million in grant funding to begin a pilot program with Avery Brewing to see if it could minimize the use of costly and potentially harmful chemicals like methanol or acetic acid. Avoiding chemical use would also reduce life-cycle greenhouse gas emissions.

Now, this innovative program is poised to become a permanent part of the treatment routine, with the installation in summer 2016 of a 6,000-gallon storage tank for the weak wort on Avery’s campus.

The partnership is a win-win. The city gets the valuable wort for free, while Avery has a way to dispose of it safely.

It is also an example of public-private ingenuity and innovation at work. The partnership became a reality after a process engineer at the wastewater facility suggested the city consider tapping into an emerging trend of using industrial byproducts to support other important processes. 

“We looked at a lot of different products,” said Cole Sigmon, the process engineer, “and Avery was one of the first to respond.”

“To take what is normally a waste stream for our brewery, and have it turned into a useful component for our city’s wastewater system, is truly a unique opportunity that we couldn’t be more proud to be a part of,” said Steve Breezley, chief operating officer for Avery Brewing.

The estimated total cost of the 2015 Nitrogen Upgrades Project is $4.5 million, which includes modifications to existing nutrient removal basins at the facility and the external carbon and feed tank going up at Avery.

Sigmon is proud not only of the project, but of the commitment it represents to the community.

“We have a big utility out here, and there’s a lot of rate payer money invested here,” he said. “We have a core purpose, but we’re starting to think of ourselves as more of an environmental campus. I’d love for people to look at us and say, ‘Hey, that place is pretty cool. They are doing some really cool things.’” 

This article originally appeared in the April/May 2016 issue of the city's Community Newsletter.