It looks gross but who would have thought it was deadly too?

It might not seem like a big deal but that green gunk that builds up in swamps, ponds and local lakes can actually be the quite the problem. Yes, it looks gross and it's not pleasant to touch but it can even be harmful to the aquatic life in the ecosystem.

Harmful algae? It sounds like it's something from a 1950's sci fi movie but it's real and apparently it can shut down local beaches.

It's called harmful algal blooms or HAB's.

According to the National Oceanic and Atmospheric Administration, when harmful algal blooms grow out of control it can be devastating if the issue is left untreated. The microscopic blooms in algae can contaminate the water source while releasing toxins that can make birds, fish and mammals sick and could even kill them. The harm that HAB's cause is still being studied.

The NOAA states that harmful algal blooms are caused by a variety of factors like runoff from farms, chemicals and even sewage.

According to Putnam County Online, one beach has recently been closed because of HAB's. They report that as of July 26, Carraras beach on Lake Peekskill had been shut down. Hopefully, they can get the algal blooms under control.

If you're looking to cool off you may want to choose a different beach temporarily.

You can check the status of several beaches in the county for closures at the link above.

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