By Brad Segall

NORRISTOWN, Pa. (CBS) — With the mercury is expected to hit the 90s this holiday weekend in the Philadelphia region, it’s likely that some people will use the local creeks and streams to cool off.

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But one water rescue expert says that’s not a good idea.

More than ten inches of rain in the area during the month of June has pushed water levels to near flood stage in many creeks in the Philadelphia suburbs.

That creates a dangerous situation, as we saw this week in the Pennypack Creek in Northeast Philadelphia (see related story).

John Remillard is with the Gladwyne Fire Company, one of the swift-water rescue units in Montgomery County. He says what starts as a day of fun can quickly become dangerous.

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“An area that you swam in your entire life with just a couple of inches of rain can change dramatically and now it’s a hazard that you’re not going to be used to, and you’re not going to be able to extract yourself out,” he warns.

Remillard says those creeks hold many dangers you can’t see, such as branches and tree limbs that can trap you and dams that create elevation changes that can suck someone under the water.

“Anything that has a waterfall-type change in elevation, you can have a hydraulic effect which will turn the water back towards the dam, almost like a washing machine, and will trap anything in it.”

If you do decide to swim in a creek, his best advice is don’t go alone and make sure you’re wearing a personal flotation device to keep you from going under.

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