Residents in the City and Town of Dunkirk are being ordered to boil and conserve water until further notice.
The Chautauqua County Department of Health says construction at the Dunkirk water plant has caused a large leak which may allow treated water to become contaminated.
The health department says water levels in the city are critically low.
All Dunkirk water customers are ordered need to bring water to rolling boil before use preparing food, brushing teeth, or consuming in any way.
To conserve water, customers are asked to take fewer showers, run only full loads of laundry, use paper and plastic plates for eating. Commercial customers are asked to close today to conserve water.
Jodi Witherell, chief nursing officer and vice president of quality services at Brooks Memorial Hospital, said there's a contingency plan in place.
Witherell says patient care is not affected and no medical procedures have been postponed or cancelled.
Employees covered faucets to prevent patients and staff from using water right now. Hospital officials say there is ample bottled water for drinking and cooking. There are portable hand washing stations set up in the hospital.
Chautauqua County officials say they will get the first water test results back on Friday. They'll also conduct another round of water testing.
If all of the results come back at safe levels, the boil water advisory will be lifted Saturday. If bacteria levels are too high, they will retest. There needs to be clear tests over 48 consecutive hours before the advisory is lifted.