JACKSONVILLE, Fla.-- There are new fears over a toxic danger in the St. Johns River.
Action News has just learned testing will be done this week on green algae popping up in the water. It's a big concern for Jim Alaviso. He's supposed to swim six miles in the river on Saturday.
"A report I saw last week showed the river was healthier this year than last, so I was a little surprised we have bloom," said Alaviso.
"It's perfect weather conditions to get slime in the St. Johns," said St. Johns Riverkeeper Lisa Rinaman.
The Riverkeeper tells Action News the green slime started popping up just a couple weeks ago. "We've had a lot of rain followed by patches of dry, hot periods," said Rinaman.
Now she tells us they're going to do testing to see if it's toxic. The last major algae blooms were in 2009 and 2010. Green swirls filled the river, killing fish and forcing people out of the water for their own safety.
So as for swimming Saturday, Alaviso said, "That's a good question. It depends on the swimmer, what risks they're willing to take, and where it is."
But if he doesn't swim the 6 miles, Alaviso said they'll hop in the boat to spread the message about the St. Johns River.
"If we don't swim because of the algae, we have a good message," said Alaviso.
We're told the results for the tests will be done by the end of the week.
As for the 10K swim Saturday, Action News was told that decision will be made that morning.
You can read the latest report on the health of the St. Johns River by clicking here
. To read the river accord report, click here