Keeping an eye on Lake Okeechobee ahead of rainy season

Flows from Lake Okeechobee hydrate the area and balance salinity, but if the timing or amount of water is wrong, there could be adverse effects. WINK News has updates on Lake Okeechobee as Southwest Florida enters the rainy season.

The scenic Caloosahatchee River looks and functions much differently now than it did in the past when it first fostered settlement in Southwest Florida.

“Before the dredging and ditching and draining started back in the 1800s, the Caloosahatchee was actually mostly a separate watershed,” said Matt DePaolis, environmental policy director for the Sanibel-Captiva Conservation Foundation. “It had its own flow patterns, it had its own ecosystem that was centered around how the freshwater coming up from the springs and some of those other watersheds sources control that ecosystem.”

These days, the Caloosahatchee River is controlled by an artificial connection to Lake Okeechobee, altering both the magnitude and timing of water delivery to the estuary. But, as DePaolis explains, we do need freshwater releases at times.

​”When we’re in dry season, we’re not getting a lot of those basin flows,” DePaolis said. “We actually require about 750 cfs coming out of the lake; that’s cubic feet per second coming from Lake Okeechobee.”

The flip side is when we get too much water from “damaging discharges.”

​”That just nutrient-laden water is so polluted with new nitrogen and phosphorus that when it flows out into our estuary, it feeds more algae blooms,” DePaolis said.

In addition to potentially carrying its own toxic algae blooms, satellite imagery from the lake shows bloom potential on the western shoreline. In our neck of the woods, sampling for cyanobacteria by the Lee County Environmental Lab showed moderately abundant levels of microcystins at Alva Boat Ramp and the Franklin Locks.

“When we start seeing the algae blooms on the lake, then the Army Corps [of Engineers] is really worried about transmitting those algae blooms through the canals, through the lock systems, and out into the estuaries, so that’s when we’ll start to see some of the releases be cut off to prevent moving those toxic algae blooms,” DePaolis said. “And that’s not good for us because that water does need to go somewhere at some point, and the lake can only get so high before we need to discharge it.”

As we enter the rainy season and the lake levels are expected to rise, Lake Okeechobee currently stands at 13.88 feet.

“If we’re going into a wet season, where the lake is already a foot higher than it was a year ago, we have the potential to really get that lake up to a dangerously high level, if we don’t do something about it,” Depaolis said.

DePaolis hopes the lake level will continue to go down and the blue-green algae will clear up so we can continue to get healthy discharges without consequences. The aim is for Lake Okeechobee to be at a level that supports its submerged aquatic vegetation and other wildlife habitats.