PUNTA GORDA — The city of Punta Gorda will be issuing notices regarding the drinking water for area residents on the city’s utilities system.
For some residents in the northwest section of the city’s utility area, which encompasses the city and some surrounding Charlotte County areas, recent testing found higher than average levels of TTHMs, or Total Trihalomethanes. TTHM is a disinfection byproduct required by the Florida’s Department of Environmental Protection standards for drinking water to “inactivate possible pathogens,” according to the city’s Oct. 4 weekly highlights report.
Since this finding, the city has gone from testing the water quarterly to a weekly basis.
“No boil water notice is needed as TTHMs do not pose an immediate health threat,” said city spokesperson Melissa Reichert. “Problems for some people can occur with years of exposure to TTHMs.”
This is the first time the TTHMs were above the limit at any of the sample sites, according to Reichert.
“Previous quarterly samples were in compliance and the most recent re-sample of the site following the elevated result was in compliance,” Reichert said.
The DEP requires TTHMs, as well as Haloacetic Acids (HAA5s), according to the city, because the health benefits of disinfection outweigh the risks that come with said pathogens.
“According to the Environmental Protection Agency, long term (years of) exposure to high doses — they do not define what’s considered high — could, in some people, cause liver, kidney issues and possibly cancer,” said Reichert.
Two recent samples collected at the 600 block of Shreve Street within the water system revealed an annual average TTHM concentration of 82.9 micrograms per liter.
The standard is 80 micrograms per liter.
That led the DEP to determine the area was in “Maximum Contaminant Level” violation.
“Once we got the elevated sample results, the city re-sampled the sample site and (we found that) the re-sample results were (actually) below the limits,” Reichert said. “We then, however, increased the sampling frequencies, began splitting − sending duplicate samples − to several laboratories to check for laboratory error and began flushing the area of the elevated sample.”
TTHMs are formed in the pipe when chlorine reacts with carbon in the water and the one sample point was the only sample that was elevated, Reichert said.
Since finding these results, the city has begun an aggressive flushing routine for this site and will be testing for the contaminants listed above on a weekly basis, rather than quarterly.