E. coli or enterococci, which indicate fecal matter contaminating water, were detected at swim spots in New York state, Massachusetts, Michigan and elsewhere, authorities said.

Just ahead of the long Independence Day weekend, beaches across the country have closed and issued advisories because of excessive levels of harmful bacteria. The culprit is fecal waste, a common summer problem in both freshwater and oceans that can cause gastrointestinal illness and skin infections.

Dozens of beaches across several states are closed or have health advisories in place due to elevated bacteria levels.