Some water fountains at Farmingdale schools are turned off in response to drinking water standards.
A letter from the superintendent says the district is testing water and making immediate changes at all six schools.
The letter say the testing comes in response to new state standards that lower the threshold for likely carcinogens called PFAS in drinking water.
The district says in the long term, the district will be replacing old drinking water fountains with new ones that have filters.
Statement from Paul Defendini, Superintendent of Schools:
"The Farmingdale School District is updating its drinking water systems after recent testing, performed under stricter new New York State standards (lowered from 15 ppb to 5 ppb), identified the highest volume of fixtures requiring remediation since 2016. Any location testing above the new 5 ppb threshold has been immediately taken offline or designated "Hand Washing Only," and the district is now planning a full transition to modern, filtered bottle filling stations district-wide."