{"UUID":"512bf5f1-1c75-400d-a899-87fc9f28f014","URL":"https://indyweek.com/news/archives/human-error-caused-owasa-fluoride-overdose-owasa-sorry/","ArchiveURL":"https://web.archive.org/web/20210226170650if_/https://indyweek.com/news/archives/human-error-caused-owasa-fluoride-overdose-owasa-sorry/","Title":"OWASA fluoride overfeed and water main break in Orange County, February 2017","StartTime":"2017-02-02T11:43:00Z","EndTime":"2017-02-02T14:40:00Z","Categories":null,"Keywords":["owasa","fluoride","water treatment","operator error","water main","orange county","chapel hill","carrboro","water"],"Company":"OWASA","Product":"water treatment plant","SourcePublishedAt":"2017-02-10T14:37:00Z","SourceFetchedAt":"2026-05-04T18:13:58.099449Z","Summary":"The wrong push of a button lead to a water treatment plant shutting down due to too high levels of fluoride.","Description":"On February 2, 2017, at 11:43 a.m., a water treatment plant operator at OWASA accidentally instructed the plant's fluoride feed pump to increase its feed rate to 80%, significantly higher than its normal operating range of 8-12%. Although the operator attempted to correct the command about twelve seconds later, the change did not register. The pump continued to operate at the elevated rate for approximately 3.25 hours, leading to a fluoride overfeed condition. A lead operator noticed the high fluoride levels but failed to take corrective action, and the issue was not resolved until after 2:40 p.m. The following day, February 3, a separate water main break occurred.\n\nThe fluoride overfeed was attributed to an \"unintentional operator key stroke\"—a human error where the wrong button was pressed. The subsequent failure of a lead operator to act on the observed high levels prolonged the incident. The water main break was potentially caused by pipe bending due to pressure and settling, possibly exacerbated by its shallow burial.\n\nThese incidents led to a severe water shortage in Orange County. Businesses closed, and both Chapel Hill and Carrboro declared states of emergency. Residents were advised not to use or drink their water for over twenty-four hours, prompting a rush to buy bottled water. Fluoride levels at the plant reached 5.90 mg/L, exceeding state and federal primary drinking water standards by 1.9 mg/L.\n\nIn response, OWASA temporarily halted the addition of fluoride to the water supply. The OWASA board of directors committed to developing solutions to prevent similar failures, assessing broader outage risks, and improving water system resiliency and communication practices. The agency is reviewing its policies and seeking public input before reintroducing fluoride to the water supply."}