Florida’s dry season has started, but Lake Okeechobee has little chance of recovery from the damaging high lake levels this year.
“We’ve had a smooth transition in the dry season, which started around Oct. 1,” Col. James Booth, commander of U.S. Army Corps of Engineers (USCAE) Jacksonville District in an Oct. 27 media briefing.
“Even with the dry season upon us, hurricane season continues until the end of November,” he added. “We’re looking forward to calmer weather in the future.”
On Oct. 27, the lake was 16.24 feet above sea level, about 8 inches higher than 30 days ago and 6 inches higher than this time last year. The levels best for the lake's ecology range from 12.5 feet (or below) at the start of the wet season to 15.5 feet at the start of the dry season.
For the seven-day period ending Oct. 27, inflows into the lake from the north averaged 2,470 cubic feet per second (cfs). Outflows from the lake to the Caloosahatchee River at the Julian Keen Jr. Lock at Moore Haven averaged 1,215 cfs. Flow at the W.P. Franklin Lock – more than 43 miles from Moore Haven – averaged 1,945 cfs, a combination of lake releases and local basin runoff.
The target flow, measured at the Franklin Lock, is 2,000 cfs, which is in the beneficial flow range for the Caloosahatchee estuary. The river needs freshwater flow from the lake in the dry season to prevent the estuary from becoming too saline. If local basin runoff meets or exceeds the 2,000 cfs target flow, no lake water is released.
To the east, no water was released through the Port Mayaca Lock or the St. Lucie Lock. Booth said the C-44 reservoir is about 7 feet deep. Water from the C-44 canal (St. Lucie canal) is pumped into the reservoir and then cleaned in a stormwater treatment area (STA). Flow from the reservoir in the STA averaged 35 cfs to keep the vegetation hydrated and clean the water.
Booth said since the start of wet season, about 260,000 acre feet of water has been “banked” in Lake Okeechobee. That’s the difference between how much water would have been released if they followed the release guidelines of the Lake Okeechobee Regulation Schedule of 2008 (LORS-08). The "banked" water represents about 7 inches on Lake Okeechobee.
USACE plans to switch from LORS-08 to the new Lake Okeechobee System Operating Manual (LOSOM) in 2024.
South of the lake, so far this year, about 1 million acre feet of water has flowed under the Tamiami Trail to Everglades National Park (ENP). Booth said they hope to total 1.4 million acre feet to ENP by the end of the year.
For the seven-day period ending Oct. 27, flow under the trail averaged 3,100 cfs.
Water Conservation Areas (WCA) 2A and 3A continue to be above schedule, he said.
Water control structure S-12A is scheduled to close Nov. 1, but may only partially close until maintenance is complete. S-12B is scheduled to close Dec. 1.
Booth said USACE received a lot of feedback from the Miccosukee Tribe, Florida Fish and Wildlife Conservation Commission and the South Florida Water Management District about the damages and threats to wildlife caused by high water levels in the WCAs.
“We are currently in the process of requesting a temporary planned deviation through the combined operating plan for the closure dates for S-12s and S-343s,” he said. (SFWMD controls the S-343 water control structures, but federal law requires them to be closed part of the year.)
He said they hope to have a planned deviation approved between Nov. 15 and Nov. 20. The planned deviation notice should be out for public review next week, he added.
“It’s not going to be in time to prevent the closing of S-12A on Nov. 1,” he said.
He said the S-12 C and D gates will remain open as long as water levels in WCA-3A are high enough for gravity flow to the move the water.
Booth said dry conditions over the past week have helped the water levels in the WCAs to recede but WCA-2A and WCA-3A are still above schedule.
He said due to high water conditions, FWC had closed WCA-3A to the public. FWC reopened public access on Oct. 26.
Booth said USACE is working on the dry season strategy. He said it is unlikely they will be able to bring the level of Lake Okeechobee down to 12.5 feet by the end of the dry season.
The lake needs levels below 12.5 feet for about 60 days in order for new submerged aquatic vegetation (SAV) to sprout and grow, he explained.
“I don’t think we’re going to see recession on the lake low enough or long enough to have significantly positive impacts on SAV,” he said. The lake is pretty high, above 16 feet, and we’re also doing into a dry season with an El Niño moving in.”
According to the National Weather Service, “During El Niño, trade winds weaken. Warm water is pushed back east, toward the west coast of the Americas. El Niño means Little Boy in Spanish. South American fishermen first noticed periods of unusually warm water in the Pacific Ocean in the 1600s. The full name they used was El Niño de Navidad, because El Niño typically peaks around December. El Niño can affect our weather significantly. The warmer waters cause the Pacific jet stream to move south of its neutral position. With this shift, areas in the northern U.S. and Canada are dryer and warmer than usual. But in the U.S. Gulf Coast and Southeast, these periods are wetter than usual and have increased flooding.”