For the second time this year, the water in Upton, Mass., is contaminated with E. coli or fecal coliform bacteria.
The contaminant was found in the water supply at a West Upton pumping station last week. Yesterday, test results came back indicating it had spread further, said Board of Health member Sue Cudmore.
Unlike when the contamination was found in August, residents were not asked to boil their water or switch to bottled water.
Instead, the water department immediately started adding chlorine to the water, in an effort to protect the 1,200 homes and businesses relying on public water.
Some residents have noticed a slight discoloration in the water. Aquarium owners and those using kidney dialysis machines were advised to treat or filter the water before use.
Along with adding chlorine, the department is flushing the water system, investigating the contaminations source, and hastening testing efforts.
Meanwhile, the state Department of Environmental Protection is conducting its own tests to make sure the town's wells are not drawing in contaminated surface water.