The controversial re-introduction of fluoride will be delayed 12 months while experts operate a miniature mock-up of the water system to test for possible increased lead levels.
The risk of lead leaching is very low, according to a consultant hired by Windsor Utilities Commission. But the 12-month pipe loop study was urged out of an abundance of caution “to ensure that lead release does not increase after fluoride introduction.”
The study will delay fluoridation until November 2021, commissioners were told Wednesday during a progress report on the re-introduction. The city has been without fluoride more than six years and the study will mean another year delay, but WUC officials believe they can do nothing else but recommend the study, said Helga Reidel, CEO of Enwin, which manages the water system for WUC.
“It’s too important. This is the water system,” she told commissioners, who approved the study.
After a previous city council removed fluoride in 2013, a 51 per cent rise in serious tooth decay among kids over five years and the pleadings from local dentists and the Windsor-Essex County Health Unit convinced the current council to reverse direction. In December 2018, they voted 8-3 to resume fluoridating the water supply. But it’s up to WUC to actually do it, a process that will cost an estimated $635,000 for startup costs and about $150,000 annually to operate.
The pipe loop study, said Enwin vice-president of water operations Garry Rossi, will provide the “highest level of certainty that lead levels will not be adversely affected.”
The concerns all centre around efforts during the last several years to eliminate leaching of lead from lead water lines into the water. WUC has been replacing its lead water lines. Out of about 70,000 customers, about 15,000 had lead services — the WUC-owned water lines that run between the water main and the property line — a few years ago. That number has been reduced to 6,000 with the goal of getting to zero by 2026. But there remains roughly 15,000 households that still have lead piping on their property, Rossi said.So starting in 2016, WUC added phosphoric acid to the water supply as a corrosion control, creating a protective barrier inside lead water lines to stop the lead from leaching into the water. And it has worked, Rossi said, citing a dramatic improvement in water testing results.
But what happens when you add fluoride to a system that already has corrosion control? It’s a question that needs to be answered because it’s never been done before, Rossi said.“Chemical reactions are different. There are laws of chemistry and how they occur and why they occur, and this is one they haven’t studied,” he said.
The pipe loop study apparatus will be comprised of four circuits of lead piping that have the protective barriers. The first pipe will be fed non-fluoridated city water, and the remaining three will get water with different concentrations of fluoride. The pipes are meant to mimic the water circulation in a person’s home, where flow stops and starts when people are showering, bathing and cooking. The study needs to be done year-round because lead leaches more readily in summer. The water will be tested daily.
“We want to ensure the addition of fluorosilicic acid, which is the fluoride additive, doesn’t erode any of that protective layer and create adverse lead results,” Rossi said.WUC intends to use the highest quality of liquid fluorosilicic acid, called “high purity,” because liquid is safer for staff to use than powder, and because there were public concerns about the form of fluorosilicic acid that previously was used — a byproduct of the fertilizer production process. The high purity form costs about 36 per cent more. Total cost is estimated at between $20,000 and $30,000 annually.
WUC originally budgeted $850,000 to reintroduce fluoride, which includes the cost of the pipe loop study which starts in May. If test results are good, WUC would apply for a change to its operating licence in May of 2021 and commission the fluoridation system in November 2021. Rossi said the re-introduction won’t cause residents’ water rates to rise.
The drive to resume fluoridation originated from the health unit’s 2018 Oral Health Report, which lays out dramatic declines in the oral health of the local population. Comparing Windsor-Essex, where no municipalities fluoridate, with the rest of Ontario, where 70 per cent do, the percentage of children with urgent dental needs was double, according to the report.
But many residents strongly opposed fluoridation, claiming it amounts to “medicating” the population with a chemical they believe is harmful and minimally effective at preventing tooth decay. When council banned fluoridation in 2013, fluoridation had been happening in Windsor for 51 years.
The move to reintroduce fluoridation will also affect residents in LaSalle and Tecumseh, which rely on Windsor for their drinking water. Officials from those towns as well as the health unit were updated on the progress report on Tuesday.