Business, Conservation, Sustainability

Turning Sewage Water Into Something Drinkable

At Orange County’s Caspers Wilderness Park showers are currently unavailable for campers due to current drought conditions throughout the state of California.
At Orange County’s Caspers Wilderness Park showers are currently unavailable for campers due to current drought conditions throughout the state of California. Photo: Mechanoid Dolly | FlickrCC.

Dow Chemical Co. and Dupont Co., two American chemical industry giants that are 118 and 213 years old, respectively, recently announced a $130 billion merger deal that would take two years to complete. Led by activist investor Dan Loeb, hedge fund Third Point LLC suggested Dow Chemical split its specialty chemical and petrochemical businesses. As part of the deal, the merged company will split into three separate entities—focused on agriculture, specialty chemicals, and materials.

In the midst of this landmark deal, Dow is continuing to solidify its place as a leader in the industry—this time on behalf of California. As California continues to deal with one of the most severe droughts on record for the fourth year in a row, Orange County—with the help of Dow Chemical—is doubling down on its unusual strategy for drinking water.

Bloomberg recently toured the facility with Snehal Desai, Dow Chemical’s global business director of the water division. It’s the largest facility in the world that practices “toilet-to-tap” technology—a complex filtration system that transforms raw sewage into an end product that’s fresher than some bottled waters. The plant, located next to the county’s water treatment facility, pumps out 100 million gallons of drinking water daily, enough to supply almost 1 million Orange County residents. The county plans to increase the output of its groundwater replenishment system by approximately 50 percent.

“Recycled wastewater will probably be the single largest source of water for California over the next quarter century,” says executive director of the Association of California Water Agencies Tim Quinn. This goes for many other water-strapped regions of the world, including Australia, China, India, Israel, Spain, the Middle East, and sub-Saharan Africa, where they have developed recycled wastewater systems for irrigation. Many areas are beginning to convert their systems to create fresh drinking water. San Diego also recently announced plans to generate 33 percent of its water from recycled sewage by 2035.

Dow Chemical has been a dominant player in advanced materials engineering for more than 100 years, generating $57 billion revenue a year in 180 countries in the world. “If not Dow, then who?” asks Desai. “The future water supply is a big-ass problem. We’ve got growing urban populations, growing industries, and dwindling resources. Who can tackle something of this magnitude? You need patience and horsepower to come up with solutions and to scale them. You can’t do that without big-boy company money.”

Ultimately, Desai believes that the same technology could accommodate individual households. Every city in the world will have to start rethinking the foundation of its water supply. “Not every city has an ocean, not everyone has good lakes and rivers,” Desai says. “But everybody’s got sewage.”

Environmental Hazards, Health

Treatment Is Making Antibiotics in Wastewater Stronger

Wastewater plant
A new study looks at how antibiotics in wastewater affect our health.
Image: Shutterstock

Antibiotics in wastewater is a problem, one that scientists have known about for years. But according to a recent study by Olya Keen, assistant professor of civil and environmental engineering at UNC Charlotte, attempts to break down organic matter in wastewater is actually making those antibiotics stronger.

Chlorine is often added to wastewater in order to remove potentially dangerous organic matter within it. The chlorine is filtered out before that water is allowed to pass through to later stages. Unfortunately, chlorine isn’t able to destroy antibiotics, which pass through without a problem and can end up in streams and other water sources. Once there, these antibiotics interact with bacteria in those water sources, which can eventually develop immunity to those antibiotics.

Keen and her students isolated doxycycline, which is one of the more commonly used classes of antibiotic, for the study. They found that not only does chlorine not kill the antibiotic, it actually makes it stronger by changing its chemical makeup and creating new antibiotics.

As more antibiotics get out into the wild, bacteria will have the time and the room to adapt to them and become immune, resulting in bacteria that humans and other animals cannot fight off. This doesn’t normally happen with patients taking antibiotics, as the bacteria don’t have time to create enough generations to adapt and end up dying off.

The antibiotics in wastewater get there in a variety of ways. Any not broken down in the human body can end up being released through bodily waste, but many individuals and even hospitals dump old or expired antibiotics down the toilet, which is part of the problem. Runoff from factories and labs producing antibiotics contributes to the problem as well.

Keen’s research will give us more insight into the problem, and she hopes that it will lead to better solutions for removing antibiotics from wastewater or preventing them from entering it in the first place.