Pennsylvania American Water officials said Wednesday morning that the first set of water samples tested overnight came back with no signs of contamination.
However, the boil water advisory will remain in effect until the results from a second round of samples are tested and are clear of contaminants.
The water company had expected the advisory to remain until at least Wednesday.
Cloudy tap water prompted the boil water advisory on Monday.
The private utility said the cause of the turbidity that prompted the precautionary advisory in 55 municipalities was a malfunctioning filter at the company’s Aldrich Purification Plant on the Monongahela River in Union Township, Washington County.
The first samples were taken Monday night, the second round of samples Tuesday night.
Turbidity readings and total coliform tests are done in-house, and Pennsylvania American’s lab is certified by DEP.
But it may interfere with disinfection and allow for growth of viruses, bacteria, and parasites, the water company acknowledged on its website Tuesday.
Those “bugs” can cause a variety of health problems, including nausea, cramps, diarrhea and headaches, especially affecting people with compromised immune systems, the elderly and infants.
▪ Dravosburg: 226 Maple Ave ▪ Elrama Volunteer Fire Company: 17 Elrama Ave, Union Township ▪ Hanover Township: 11 Municipal Drive ▪ Jefferson Hills Borough Police Department: 925 Old Clairton Road ▪ Monongahela Volunteer Fire Department: 451 W. Main St. ▪ Morris Township: 77 Park Drive ▪ North Franklin Township Fire Dept., 565 Sylvan Drive ▪ North Strabane Fire Department: 2550 Washington Road ▪ South Fayette Township Library: 515 Millers Run Road ▪ South Park Township Library: 2575 Brownsville Road ▪ Upper St Clair Community & Recreation Center: 1551 Mayview Road ▪ Washington Mall: 301 Oak Spring Road, Washington, Pa. ▪ Washington Park: 900 East Wheeling Street, Washington, Pa.