Corps of Engineers starts releases from Lake Okeechobee to east and west

Corps trying to slow the rise of Lake Okeechobee

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JACKSONVILLE – “Today we are initiating releases,” Col. Andrew Kelly of the U.S. Army Corps of Engineers announced in a media conference call Wednesday afternoon. “Within an hour, we expect to see some flows coming.”

The corps will release 4,000 cubic feet per second (cfs) to the Caloosahatchee at Moore Haven, and 1,800 cfs to the St. Lucie River at the St. Lucie Lock. Water from the lake enters the St. Lucie Canal at Port Mayaca, so flow through the St. Lucie lock will be a combination of lake water and local basin runoff. In the past seven days, flow at the St. Lucie Lock averaged 506 cfs. from local basin runoff alone. Port Mayaca is 23.9 miles from the St. Lucie Lock.

King Tides will be taken into consideration when releasing water. “We are going to kind of target the releases to not exacerbate that activity,” he said.

The goal is not to lower the lake, he stressed. The goal is to slow the rise of Lake Okeechobee.

Even with an additional 5,800 cfs released from the lake, the Big O will continue to rise. In recent weeks, flow into the lake from the north has averaged 8,000 to 10,000 cfs.

“The rise is going up more quickly than we want,” said Kelly. He said the Atlantic is still active. He noted historically 20% of hurricanes that impact Florida have been in October and 5% in November.

“We need to stabilize the rate of rise, and if we can, turn it,” he said.

Kelly said the corps will execute the releases for the shortest duration possible. The corps and the South Florida Water Management District will also continue to maximize flows to the south.

“We will do the east and west releases until we can stabilize the lake,” he said. “Once that is done we will come up with dry season strategy.”

Heavy rainfall south of the lake has limited southern releases, he explained. The southern end of the system is very wet, and it’s been wet for a while during this wet season, Kelly explained. “Over the course of the last couple of months, the water management district has been doing a phenomenal job moving water.”

Kelly said the flow at the Franklin Lock will not be less than it was earlier this summer from local basin runoff alone.

“What we have seen in the past couple of months, we have seen pretty high flows out the Caloosahatchee not from the lake but from basin runoff, up to 8,000 and 10,000 cfs,” he explained. The Franklin Lock is 43.3 miles from Moore Haven.

With 4,000 cfs entering the river at Moore Haven, “once you get all the way to the end, it won’t be that much difference,” he said.

Kelly said with releases at this rate for a month, flow will total equivalent in total volume of approximately half an foot on Lake Okeechobee. How much the lake will continue to rise despite these releases depends on many factors, he explained.

“It depends on how much water comes into the lake. It depends on the weather, it depends on the rain,” he said. It also depends on how much water leaves the lake through evapotranspiration. Over a year’s time, most of the water that leaves the lake is by evapotranspiration (a combination of evaporation into the air and transpiration from plants).

“We will reduce or stop the flows as soon as we can,” said Kelly. They anticipate releases will be needed for about a month.

He said they have monitored algae in the lake and find no problems with algae near the release areas.

“FDEP has done a phenomenal job this year increasing the monitoring of water quality and algal blooms in Lake Okeechobee. There is a lot more real time information that we have,” he said. “The Florida algae task force is working on ways to improve the science and become more predictive.”

Kelly said this late in the season there are fewer algae blooms because algae thrives in hot, still water.

“Conditions are better at this time of year than in the mid summer,” he said. “Recent samples have come back pretty good, we’re not seeing an abnormally high algae year on Lake Okeechobee.”

“It’s better later than it would have been in the extreme heat of the summer,” Kelly said.

“There is algae on the lake. Recently it has been mostly towards the middle of the lake,” he explained.

“As rain and wind disrupts algae bloom formations, it’s looking pretty good right now,” he said.

Lake Okeechobee was at 16.21 feet above sea level on Wednesday. Seven days ago it was 15.92 feet.

In recent weeks, water has been flowing into the lake nearly 10 times faster than it has been released. For the past seven days, flow into Lake Okeechobee has averaged 8,073 cubic feet per second while flow out of the lake south has averaged 820 cfs. On Tuesday, flow south was 1,859 cfs.

No water has flowed east to the St. Lucie at Port Mayaca since spring 2019. However, sine the 2020 wet season started in May, more than 70 billion gallons of water from the C-44 basin has back flowed into Lake Okeechobee at Port Mayaca. According to Kelly, in 2020 enough water flowed into the lake from the C-44 canal to raise the lake level about 6 inches. (One inch on Lake Okeechobee is about 12 billion gallons of water.)

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