From The Fort Morgan Times (John Brennan):
The surges have been happening periodically over the last couple of months, usually at night, he said. City officials are trying to determine what is in the wastewater stream and where it’s coming from. [Water Resources Director Gary Dreessen] said he has contacted the city’s wastewater consultant and state officials, and both believe that “we’re being hit by something,” he said — meaning that someone is putting a large amount of an unknown substance into the sewer system.
More wastewater coverage here.