According to The Buffalo News:

The Niagara County Health Department announced Wednesday that swimming has been barred until further notice at three campgrounds and at Krull Park Beach in Olcott because of high bacteria levels in water samples taken this week.

The affected campgrounds are Niagara’s Lazy Lakes Campground, on Church Road in Cambria; Niagara County Camping Resort, on Wheeler Road in Hartland; and Niagara Hartland Campground, on Hartland Road in Hartland.

This is the third time this summer that Krull Park Beach, on Lake Ontario, has been closed because of elevated bacteria levels. The campgrounds, located inland, are affected for the first time this season.