JACKSONVILLE, Fla. -

Some algae blooms have been spotted in the St. Johns River from St. Johns County to Arlington.

Lisa Rinaman, the Riverkeeper, says researchers took samples of the algae at Jacksonville University and other locations, and the type of algae was identified as microcystis, the same type that extended the "Green Monster" event in the St. Johns in 2005.

There was no word yet on the levels of the toxin in the river.

There is concern about this weekend's Up the River event, a 10k swim and group boat, paddle and kayak ride, though Rinaman said the event will take place.

Organizers may have to shorten the swim or only hold the boat rides.

Rinaman said recent, heavy rains may have washed too many nutrients into the river, and with the hot, dry periods that followed, it has created ideal conditions for algae.

The event aims to bring awareness to a healthier river and healthier lifestyle. It also benefits the Special Olympics.

For more information about the event, click here.