Water customers in Guilford Township, Franklin County are being told to boil their water before drinking it.
Department of Environmental Protection spokeswoman Amanda Witman said boil water advisory was issued after the township's water chlorine level went below the minimum standard for 12 hours from Sunday evening through Monday morning.
Witman said DEP took 10 samples of the water on Monday and an additional ten samples Tuesday.
She said the results should be in Wednesday.
If the tests samples come back within normal levels, Witman said the boil water advisory should be lifted Wednesday.