Blue-green algae discovered in three Polk County lakes

Another three lakes in Polk County were added to a growing list of places with algae blooms. 

The Florida Department of Health just issued an alert for Lake Mattie, Lake Hancock and Lake Crago. This means there were significant levels of blue-green algae discovered in these lakes. 

"We just had a recent test on Lake Crago that algae blooms were detected near the boat ramp," Kevin Cook, spokesman for the City of Lakeland said. "However, none of the harmful toxins which impact those with respiratory and breathing problems were detected."

RELATED: Polk County health officials issue blue-green algae alert for Lake Crago

If algae blooms really take hold, the tiny microorganisms produce potentially dangerous toxins that can cause medical problems that include skin irritation and difficulty breathing. When the situation becomes that serious, health officials recommend that people don’t fish, water ski, swim or recreate on the lake. They also said to keep dogs and other pets away from the water.

Blue-green algae is naturally occurring in Florida, and blooms are inevitable this time of year. 

"It is worse when it is sunny and hot outside," said Pamela Acosta-Torres, spokesperson for the Florida Department of Health in Polk County.

One thing residents can control that encourages algae blooms is run-off with fertilizer. This causes algae to multiply exponentially, and that's why many local counties limit the use of fertilizers that contain nitrogen and phosphorus. 

In Polk, Hillsborough, Pinellas and Sarasota counties, you’re not supposed to use those fertilizers from now until the end of September. In Hernando, the ban runs from January 1-March 31 and in Pasco, it is year-round.

Residents also aren't allowed to fertilize before it rains.