The surface of Lake Okeechobee is expected to turn the wrong color this summer as all the elements for a huge outbreak of blue-green algae are in place.

Warm water, ample sunlight, and calm weather is what blue-green algae needs to flourish, and those conditions are present in South Florida every summer. But the key ingredient for any harmful algae bloom in the lake - nutrients - are usually stuck down in the muck.

But what is “usual” has changed in South Florida since Hurricane Ian. Stronger tropical cyclones caused by warming ocean waters due to rising temperatures worldwide are tilting environmental conditions in favor of worsening natural disasters, and that includes harmful algae blooms such as blue-green algae and red tide.

Last fall’s Category 4 storm whipped up waves on Lake Okeechobee and churned up the bottom, where accumulated layers of phosphorus and nitrogen that washed off nearby industrial-scale farms and settled long ago were stirred up into the water column.

“What you have is a perfect storm of possibility for blue-green algae blooms that are going to feed off those nutrients,” said Gil Smart, the director of VoteWater, a nonprofit working to stop algae-laden discharges from Lake Okeechobee. “We've seen both federal and state water managers sound the alarm about the potential for this.”

_________________________

Read also

Seagrasses have been in decline in Tampa Bay for three years in a row. Here's why

WUSF Public Media - WUSF 89.7 | By Steve Newborn

Published February 15, 2023

‍

_________________________

The Army Corps of Engineers decides when to let water out of Lake Okeechobee, both to protect the integrity of the Herbert Hoover Dike that rings the shoreline and to try and restore something close to the water flow nature intended. The lake’s release valves are the Caloosahatchee River to the west and to the St. Lucie River to the east.

If the water in the lake has got to go, and there is an active algae outbreak on the surface, the harmful bacteria goes with it as happened last time the lake was covered with putrid blue-green algae in 2018.

“It absolutely clogged the St. Lucie River: It was grotesque. It smelled. It caused all sorts of problems. Businesses closed. Fish and wildlife died,” VoteWater’s Smart said. “We cannot afford another summer of slime.”

The hurricane effect

The similarities between Hurricane Ian in 2022 and Category 3 Hurricane Irma in 2017 are driving both anxiety over harmful algal blooms like red tide that have already happened, and anticipation of a massive blue-green algae outbreak on Lake Okeechobee this summer.

Hurricanes Ian and Irma share far more than their first letter. Each made landfall in Southwest Florida. As a major hurricane. In September. And each hurricane’s strong winds riled up Lake Okeechobee. Both were followed by another, lesser but still powerful water-churning hurricane, Maria and Nicole, respectively.

That major blue-green algae outbreak on the big lake in 2018 that Smart described, which spread throughout both the St. Lucie and Caloosahatchee estuaries, occurred the summer after Hurricane Irma.

‍