SANDY — An independent investigation by an engineering firm looking at last year’s fluoride overfeed in Sandy that sickened hundreds of residents reveals missteps at all levels by government agencies handling the emergency.

Those agencies include the city of Sandy, the Salt Lake County Health Department and the state division with responsibility over regulating drinking water.

Specifically, the 181-page report produced by Hansen, Allen & Luce shows there were problems with coordination and documentation of conversations among the agencies involved and lapses in communication that led to a failure to notify the public to refrain from drinking the contaminated water — until 10 days after the release happened.

Testing in some samples showed fluoride at 40 times the federal threshold.

“(The drinking water division) and the (Salt Lake County Health Department) both have requirements in relation to public notification,” the report said, noting that the public notification process resulted in delaying documents to affected residents in an adequate fashion.

A statement from Sandy said it has implemented 30 of the 35 recommendations contained within the report, with the remaining steps being undertaken.

“This report provides valuable insight into the causes of the fluoride overfeed event and identifies improvements. Sandy City is systematically implementing these recommendations and will continue to work diligently with county and state regulators to ensure Sandy drinking water is safe,” said Tom Ward, Sandy’s public utilities director.

Ward was put on administrative leave in the aftermath of the overfeed that sickened hundreds of Sandy area residents but was later reinstated after an independent legal investigation.

The report found that the overfeed of concentrated hydroflurosilic acid, 14 gallons, was triggered Feb. 5, 2019, due to a combination of factors at the Paradise Valley well, which had not been running since July of 2016.

Despite that, the flow switch on the fluoride pump was stuck in the open position and for a reason the city couldn’t explain, a visual alert for an alarm had been removed. The report said there was no indication that the switch was faulty.

The well’s pump was operational, and when an alarm went off and was cleared, the fluoride pump began to work, discharging the fluoride. Because it is 20% denser than water, it displaced the water and was fed by gravity into a portion of the drinking water system.

Residents began to complain as early as Feb. 6, when the first resident was informed by the public utilities department that it was a water softener problem. The resident, however, didn’t have a water softener at the home.

The Utah Division of Drinking Water was notified Feb. 8 and told the city to expand what it was sampling for and the geographic area as well.

The report noted some key areas where response needed improvement among government entities, observing:

  • Sandy removed state-required items from a public notification that were not noticed in a review by the state drinking water division, including warnings to refrain from ingesting the water and potential damage to piping from the corrosive metals. It was discovered after public notices were already distributed.
  • The city should have proactively used social media and enlisted help from the news media to inform affected residents, rather than letting social media and the news media “steer” the conversation afterward.
  • On Feb. 16, 10 days after the first complaint and after the state lacked data confirming lead and copper testing results had returned to normal, the Utah Division of Drinking Water and the governor’s office required the city to issue a “do not drink” order.
  • Water system employees should be educated on the potential impacts of hydrofluorosilicic acid on human health, water system infrastructure, and plumbing.
  • Marie Owens, director of the Utah Division of Drinking Water, said the agency is reviewing the report and intends to write a response.

“We are not satisfied with all of the items in the report,” she said.

Owens also emphasized that while the division received an alert over the public notification Sandy was going to send out, it did not “review” it.

There are only two counties in Utah that have water with fluoride — Salt Lake and Davis — both the result of a public vote. While considered a dental benefit by advocates, it has its share of critics who assert it is not properly regulated, and in excess causes health issues.

Fluoride concentrate in its undiluted form is classified as a hazardous, poisonous material that, while it contains fluoride, also contains arsenic, lead, copper, manganese, iron and aluminum. It is a byproduct from phosphate mining operations.

In the aftermath of the overfeed, Sandy was hit with an administrative order from state regulators and is under protracted monitoring.

”Sandy City is up to date on their increased quarterly monitoring,” Owens said. “This will continue until it is clear there is no ongoing risk.”

*Original article online at

** See all reports on the Sandy, Utah, event