LAKE OKEECHOBEE — Expect releases from Lake Okeechobee to the coastal estuaries to start early next week.
“We have got to get water off the lake. We have got to stem the rise,” said Col. Andrew Kelly of the U.S. Army Corps of Engineers, in a Friday morning media conference call.
Heavy rainfall north of the lake means water is pouring in at a rate of about 10,000 cubic feet (cfs) per second from the north. Heavy rainfall south of the lake means water conservation areas (WCA) already full. With the South Florida Water Management District (SFWMD) doing everything it can to move water, flow south from the lake is averaging about 800 cfs.
“As the basin to the south gets more saturated with rainfall, you basically just run out of room,” said Kelly. “It would be a totally different situation if the WCAs and area south of the lake were drier.”
“It’s a complex system,” he said. “Rain anywhere in the system affects our ability to move water in that direction.”
Starting early next week, the corps expects to start releasing 4,000 cfs at Moore Haven to the Caloosahatchee River and 1,800 cfs at the St. Lucie Lock to the St. Lucie River. Some of the 1,800 cfs flow at the St. Lucie will be local basin runoff. On Friday, flow at the St. Lucie Lock of 694 cfs was all from local basin runoff.
Kelly said for the first few months of the wet season, the lake was rising about 1 foot per month. In September, it rose 1.4 feet. In the last 30 days, it has risen 1.5 feet.
“We are trending in the wrong direction,” said Kelly. “The lake is rising faster and increasing its rate of rise. The basins around the lake are over schedule and very wet.
He said to slow the rise of the lake, they need to release 5,000 cfs from the lake. The only way to do that is to start releasing water east and west.
“If we do that for close to a month, we can move about half a foot from the lake,” he explained. That does not mean the lake level will drop by 6 inches, he added. Water could still be coming in twice as fast as it can be released. “Our goal is to stem the increasing rate of rise,” Kelly said.
“When we achieve that change and can stabilize to a more normal rate of rise or if the wet season ends, we will be able to stem and possibly cut back on those releases,” he said.
Kelly said he will probably make an announcement by Tuesday or Wednesday in regard to starting the releases.
The Lake Okeechobee Waterway near Moore Haven is now clear from vegetation, the colonel added.
He said they cleared about 42 acres of tussocks and floating vegetation that was blocking the navigation channel. “It took us about a week and a half using mechanical and some EPA approved herbicide,” he explained.
Algae on the lake is not a problem at this time, he continued. While there are algal blooms on Lake O — normal for this time of year — there are no toxins near the water control structures.
The state has increased its monitoring about fourfold, he said.
“We have not had hits that contains toxins anywhere near our structures in the months of September or October,” he said. In September there were three samples with toxin levels above the 8 micrograms per liter level set by the EPA as safe for human recreational contact, but those samples were from near the center of the lake, he said. “We haven’t had anything since then.”
Conditions in the last week or so due to wind and rain have really knocked down some of that algae bloom potential, he added.
No water from Lake Okeechobee has been released to the St. Lucie since spring 2019, when the corps released water east and west in an effort to force the lake level lower by the end of the dry season.
Early in the 2020 wet season, water from the C-44 basin (St. Lucie Canal) was allowed to backflow into Lake Okeechobee at Port Mayaca. About 70 billion gallons of water from the C-44 basin flowed into the lake this year — enough water to raise the lake about 6 inches.
Since 2019, releases to the Caloosahatchee have only been “beneficial flow” in the dry season needed to prevent high salinity levels in the Caloosahatchee estuaries and saltwater intrusion into the river.
Kelly said they are watching the Atlantic and although there are no direct threats to Florida at this time, historically in October about 20% of the hurricanes affect Florida.
He said when Hurricane Irma hit in 2017, the level Lake Okeechobee rose nearly 4 feet in just a few weeks.
With the lake at 16 feet, if a storm like Irma hit now, it could endanger the stability of the Herbert Hoover Dike.
Kelly said the corps will continue to “crunch the numbers” over the weekend. “We’re going to take a couple of days, really take a hard look,” he explained.
“The earliest decision is probably Tuesday,” he said. The releases, once started, will continue until the conditions change.
“The trigger for us, after we start the releases, will be when we see a change in the rate of rise,” he said.
“If the threat of hurricanes and storms reduces and the wet season is over, that changes the dynamics,” he said. “We are committed to stopping as quickly as possible.”