In 1904, a Typhoid fever epidemic killed at least a dozen at Mendota, forced a quarantine of the facility and resulted in Superintendent Bullard's resignation in July 1904. The epidemic was traced to the sewage contaminated waters of Lake Mendota. A new sewage treatment facility was constructed in the 1920s. Prior to this, the facility dumped untreated sewage directly into Lake Mendota. In 1923, the hospital was noted to be the "principal source of dangerous pollution," but that a treatment facility was under construction.