City Of Sheridan Not At Fault Regarding 2020 Drinking Water Violation

Sheridan’s drinking water is at safe levels, however the city is going to send future samples to a different laboratory.

Although the City of Sheridan Water Supply and Treatment Division did its job in collecting water samples in a timely manner, an error by a third party laboratory resulted in the city receiving a violation notice.

According to the city’s annual Drinking Water Quality Report, the error was in a sample that was checked for Haloacetic Acids (HAA’s), which are a group of compounds that can form in water distribution systems, when chlorine used to disinfect drinking water, reacts with naturally occurring organic matter in the source water. 

Long term exposure to unsafe levels has been linked to many complications such as cancer, birth defects and skin irritations.

The recommendation for HAA’s in drinking water is 0.060 milligrams or less per liter of water.

One sample supplied by the city to the third party lab, came back with a measurement of 0.0724 milligrams per liter, which exceeds the recommendation by 0.0124/mpl.

However, the lab reported there was a processing error, when analyzing the sample.

Regardless, the city was given a violation notice for the 2020 compliance period.

Due to ongoing lab concerns, the division says it has switched to an alternate laboratory for future disinfection of by-product samples.

This does constitute a Tier 3 violation according to EPA guidelines, however this does not have a direct impact on human health, and there is nothing that the public needs to do at this time.

Water for the city of Sheridan comes from the Upper Big Goose Creek Watershed, which is an area of land that collects water into the Big Goose Creek, above the mouth of the Big Goose Canyon.

Of the samples provided to the lab, one had an HAA reading of 0.027/mpl which is below the recommendation.

The average HAA reading of all samples was at 0.0428/mpl.