Officials in Springfield, Massachusetts, say the city's water system continues to have higher-than-acceptable levels of a type of acid.
HAA5 is a byproduct of disinfection, when chorine used to treat water interacts with organic acids from broken-down plants.
The problem in Springfield goes back to 2018, when dry weather followed by above-average rainfall caused a heavy runoff into the Cobble Mountain Reservoir.
State environmental officials say HAA5 is believed to cause health problems only with long-term or lifetime consumption.
"We're working very hard on this," said Jaimye Bartak, a spokesperson for the Springfield Water and Sewer Commission. "It's something that we take very seriously. But in the meantime, we know this is concerning to customers, but the water is safe to drink and use as normal."
Bartak said the commission is working to upgrade its treatment plant to help with the problem.
"We started a pilot test back in the fall that will go throughout this year, and that will help inform the treatment plant upgrades that we will make," Bartak said. "It's a large construction project, and large upgrades will add more filtration that will eliminate this problem."
Residents of Ludlow, Agawam, Longmeadow and East Longmeadow are also affected as their towns use water from Springfield.
