(San Francisco) Using a slim glass, Aaron Tartakovsky savors a beer with a golden hue and a light fruity aroma. But behind its apparent simplicity, the brew relies on an unexpected ingredient: recycled wastewater from a San Francisco building.
The foam was brewed to raise public awareness of the “untapped potential” of these seemingly repulsive liquid sources, at a time when the American West is struggling with chronic droughts worsened by global warming, explains the head of the company. recycling company Epic Cleantec.
“Beer has brought people together since the dawn of humanity,” he told AFP. It was therefore “an incredible way” to show the general public “that in a time of climate change […], recycled water is an excellent way to ensure the safety of our communities for generations to come . »
Its vintage contains water from the showers, sinks and washing machines of a skyscraper with 550 apartments, where the company treats the water in the basement and returns it directly in a closed circuit to the 40 floors. Enough to power the toilets or the irrigation system.
Redirecting it to taps, so that it can be drunk, is prohibited by California law. But once filtered, the grayish water filled with disgusting particles actually becomes crystal clear. So much so that it “meets or exceeds federal drinking water quality standards,” insists the entrepreneur.
To prove it, he teamed up with a brewery to create a beer inspired by German Kölsch.
Epic Cleantec technology purifies water in three stages.
The liquid first undergoes biological treatment, with bacteria that attack contaminants, as the human stomach does. The water is then filtered by microscopic membranes, measuring one thousandth the diameter of a human hair. It is finally disinfected with ultraviolet light and chlorine.
The result surprised Chris Garrett, the boss of the Devil’s Canyon brewery, who produced 7,200 cans using water from the building.
“We probably started with a cleaner base than that (of water) from the municipality”, which he usually uses for his vintages, he says.
The final taste exceeded all his expectations: one of his beerologist friends tested it blind, without being able to distinguish it from a classic beer.
“There is literally no difference, no one can notice it,” laughs the cervoise lover.
Faced with the success of this educational project, distributed free of charge during major events such as the recent climate week in New York, the two companies would like to change Californian law to be able to market the beverage.
“The public is much more ready to accept recycled water than we think,” said Tartakovsky, who served the beer at his wedding.
In the United States, some places like Scottsdale, Arizona, have long recycled sewer water via factories to water golf courses and crops. Others, like Orange County, California, return this treated water to groundwater, which acts as a buffer before it returns to the taps.
But faced with the chronic droughts suffered by the region and worsened by climate change, water sources are drying up. The Colorado River, on which millions of Americans depend, is increasingly threatened.
The authorities are therefore considering recycling wastewater for direct reuse, without going through the stage of returning it to the natural environment. After Colorado last year, California must adopt new measures in this direction by the end of 2023.
This practice, called “direct potable reuse” (DPR), has already been in force since 1968 in Namibia, in the desert metropolis of Windhoek. But it arouses tensions in America: its detractors have coined the alliteration “toilet to tap”, which ignores the recycling process, to arouse disgust.
Recycled wastewater is, however, drinkable, and even less toxic than other sources of tap water because it is treated more rigorously, according to a recent study from Stanford University.
“The public often views desalination as a preferable alternative,” observes Bill Mitch, co-author of this research. “But beyond the need to be close to the coast, […], the purification of seawater consumes much more energy than that of municipal wastewater, and costs around twice as much. »
For this professor of civil and environmental engineering, initiatives like that of Epic Cleantec help to change mentalities. In recent years, other beers using wastewater from large factories have been brewed in Arizona or Idaho.
“Each of these actions helps dilute the bad reputation created by the phrase ‘toilet to tap’,” he applauds.
