Holton's water is safe to drink

Holton water customers were recently notified that in spite of a recent violation of a drinking water contamination standard, there is no cause for alarm.

On May 13, city officials issued a statement saying that results for a public water standard collected during the first quarter of 2015 showed that the water system exceeded the standard for the maximum contaminant level for total trihalomethanes, or TTHM. While the standard for TTHM is 80 parts per billion (ppb), the average level of TTHM measured in the city’s water over the past year is 89.5 ppb, it was reported.

That amount, it was noted, does not pose an immediate risk, nor is there a need to resort to using bottled water, although it was reported that consumption of water containimg more TTHM than the maximum contaminant level over a period of several years may have an increased cancer risk. Anyone with specific health concerns related to TTHM is advised to consult their doctor.

The violation reportedly occurred during a free chlorine burnout, which is part of routine maintenance of the city’s water system, it was reported. The city has finished the burnout, and on March 1, the water system went back to using combine chlorine, which reportedly minimizes the formation of trihalomethanes.

Trihalomethanes are formed as a by-product predominantly when chlorine is used to disinfect water for drinking. They represent one group of chemicals generally referred to as disinfection by-products, resulting from the reaction of chlorine or bromine with organic matter present in the water being treated.

Trihalomethanes produced in the treatment process have been associated through epidemiological studies with some adverse health effects. Many governments set limits on the amount permissible in drinking water. However, trihalomethanes are only one group of many hundreds of possible disinfection by-products — the vast majority of which are not monitored — and it has not yet been clearly demonstrated which of these are the most plausible candidate for causation of these health effects.

In the United States, the EPA limits the total concentration of the four chief constituents (chloroform, bromoform, bromodichloromethane and dibromochloromethane), referred to as total trihalomethanes (TTHM), to 80 parts per billion in treated water.

City officials are anticipating that the problem has been resolved, although the possibility exists that the next quarter’s average may also be slightly out of compliance due to the use of free chlorine in the burnout period. Compliance is based on an annual running average, it was reported.

The city’s most current water test results for TTHM, noted on April 14, were taken from two samples, measuring 32 ppb and 35 ppb, respectively. Anyone with further questions on the matter is encouraged to contact Holton City Manager Bret Bauer at 364-2721.