The Haines Borough informed residents on Jan. 7 that testing showed it had violated drinking water standards for turbidity between August and November last year.
Turbidity, a measurement of how much light passes through a water column, is caused by solid material suspended in the water. Too much of it can interfere with how well the water can be disinfected. That means that while turbidity itself has no health effects, it can be a medium for microbial growth.
Haines water and sewer manager Dennis Durr said the problem started after the borough’s treatment plant at Lily Lake was upgraded last year and the contractor didn’t replace a flow meter. Those meters can be installed at various points in the water treatment process to help measure water moving through each stage of that process and help operators identify issues that could be affecting how well the water is being treated.
“I was just kind of operating for several weeks on instinct there,” Durr said.
The borough is required to continuously monitor for turbidity, and Durr said the levels are back within guidelines now.
There’s not much residents can do to address the problem when the water is too turbid, according to the borough’s notice. People who are immunocompromised, have infants, are pregnant or elderly could have been at increased risk from potential contaminants and should address healthcare providers about drinking excessively turbid water. According to the borough’s public notice, staff adjusted chlorine levels to compensate for filtration problems.
Durr said people do complain about the water quality often in Haines, but he hadn’t heard any specifically about the turbidity issue, which can sometimes be seen as cloudiness or discolored water. In the case of Lily Lake – which provided about half of the borough’s drinking water last year – the turbidity is caused by tannins which can cause a brownish color.
But the federal standard for turbidity in drinking water is low enough that it’s generally undetectable by the human eye and even then, “cloudy water doesn’t mean it’s non-drinkable water or in violation,” Durr said.