Krull Park Beach in Olcott has been closed to swimming because of high bacteria readings in a water quality test Wednesday, the Niagara County Health Department announced Thursday.
The closure, the first of the season, will remain in effect until further tests show the water is safe.
Ronald Gwozdek, principal public health engineer, said Lake Ontario sediment probably was stirred up because of high waves caused by flash thunderstorms Tuesday.
The beach, located a short distance east of the mouth of Eighteen Mile Creek, has been closed frequently in the past because of elevated levels of E. coli bacteria, the source of which never has been accurately determined.
In 2017, the beach was closed all year, largely submerged because of high lake water levels.