Ian Pepper and Charles Gerba have been waiting 30 years for the chance to use sewage to save the world. And in the last week of August, it looked like they might have done just that—or at least saved the sunbaked corner of Tucson that is the University of Arizona campus, at least for a little while.
Pepper, 74, is a microbiologist. Gerba, 75, is a virologist. They have spent a combined 82 years on the faculty at Arizona, and they are world-renowned experts on, among other subjects, the germs found in human waste. Their shared lab isn’t on campus, but on the grounds of a county sewage-treatment plant, where they have “sewage on tap,” as Gerba puts it. They’ve worked for years to find ways to use wastewater testing to get an early warning about the spread of disease. “Sewer mining,” they sometimes call it.
So when the University of Arizona’s president, Robert C. Robbins, announced in April that he was determined to reopen the campus in the fall, with students in dorms and some in-person classes—the first president of a major public university in the country to do so—Pepper and Gerba saw their opportunity. Over the summer, they set up a system to collect sewage at 16 manholes around campus, dropping a scoop 10 feet down into a stream of wastewater from a specific building, or set of buildings, then racing the samples back to their lab to test for the coronavirus. They collect samples three times a week, always in the morning, “around 8:30,” Pepper says. “That’s when people do their business.”
After a spring and summer of intense preparation—and not a little controversy—Arizona started moving students into dorms on Friday, August 14. Returning students were given antigen quick-tests, and could move in only if they