Fluoride is being left out of Mount Airy’s water supply pending the end of a state moratorium triggered by elevated amounts of that chemical being found in city water last month.
The use of fluoride was temporarily halted on May 6, when the problem was discovered, and won’t be resumed until later, a city official said Monday.
“We expect by the end of the month, by the end of June, we’ll be back putting fluoride in the system,” Public Services Director Jeff Boyles said.
The halting of fluoride use came at the direction of a state water-quality agency. “Our last word from the state was to hold off (using it) and they would advise us when to start back,” Boyles said.
In the meantime, the lack of fluoride does not pose any danger to the system. “It has nothing to do with the treatment of the water,” the public services director said of fluoride. “It’s just an addition to prevent dental decay.”
Elevated levels of the chemical, one of multiple substances added to the city water supply, were detected through routine testing of the system on May 6. The problem was traced to a valve malfunction on a fluoride tank at F.G. Doggett Water Plant in the Toast community.
Though it is effective in preventing cavities, excess levels of fluoride can cause symptoms such as nausea, vomiting, abdominal pain and diarrhea, according to information provided by health officials.
The situation was isolated to users of municipal water on the western side of U.S. 52, including three schools in addition to a number of restaurants and other businesses along with homes. It prompted a community-wide alert, including automated telephone calls to customers, advising them not to drink the water until further notice and to use bottled water instead.
Officials lifted the alert on the evening of May 6 after the system was flushed out and no further threat was posed. There were no reports of anyone becoming sick from the excess fluoride.
However, the further use of the chemical was halted, pending a review by state regulators. “I’m sure they just wanted to … make sure we have the equipment and procedures in place to make sure this doesn’t happen again,” Boyles said.
One equipment change will involve the installation of a smaller fluoride storage tank. In case of a future malfunction, this will limit the amount of overflow that can enter the water supply, as opposed to the full brunt of the larger tank.
The smaller container has not been obtained, but is expected to be on line later this month once the situation is re-evaluated by the state and the go-ahead to resume fluoride use is given.
“I feel comfortable that we will have the equipment and procedures in place to assure that this will not happen again,” Boyles said.
He added that the response mechanisms used when the elevated fluoride levels were detected on May 6, which also included citizen alerts being sent across social media networks, have proved to be effective in the event of such problems.
“I felt like the incident was handled very smoothly,” Boyles said of the excess fluoride.
“We had a lot of people here working hard to make sure it didn’t harm anyone — it actually could have been a lot worse had it been a different chemical.”