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

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.

The weather forecast is perfect for a day at the beach this July 4th. But more than 20 lakes and ponds are closed for swimming across Massachusetts on Friday. The closures are mostly due to high levels of bacteria in the water.