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FORT WORTH (CBSDFW.COM) – Lab technicians are testing Trinity River water to see if visitors to weekend events in Fort Worth can dunk their heads in the water to cool off.

A sample of river water was found with E. coli in it Wednesday, shutting the part of the river around Panther Island down to swimmers and tubers.

You can still do something’s on the water like using watercraft. But the threat of becoming sick from E. coli is keeping people from going in the water.

“E. coli?” river visitor Michael Sotlo said when learning the news Friday “Hearing that? It makes me not want to get in. I might come out with an extra limb or something.

Well, maybe not an extra limb, but some pretty nasty stomach and intestinal ailments. So, when weekly water tests showed high levels of E. coli it shut down tubing on the river at its normal Thursday night event.

“The state requests that you don’t allow any kind of activity in the water that would involve ingestion of water,” said Tarrant Regional Water District Environmental Director Woody Frossard.

That means no swimming or tubing.

Sunday Funday and Fort Worth Fourth, which normally have tubers lazily floating in the river enjoying the shows will now have more people on the riverbanks.

It’s likely the E. coli came from animal feces washed into the river by heavy rains.

“When you have incidences like Monday when you have a heavy, heavy rain that comes quickly, we do the testing to make sure it’s OK.” Said Matt Oliver, TRVA spokesman. “But, it’s an isolated incident.”

New water tests may show the E. coli threat is far downriver by now.

“I fully expect that since that water has passed, I expect it to go back to green,” Frossard said. “I think that water is gone. But I won’t know for sure until we get results.”

Those tests results are expected back Saturday morning.

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