Army Corps plans to halve discharges from Lake Okeechobee into St. Lucie River

After three weeks of Lake Okeechobee discharges to the east and west coasts of Florida, the Army Corps of Engineers announced a slight adjustment to its plan going forward.

For the west coast, the Corps plans to continue discharging lake water into the Caloosahatchee River estuary at the same rate is has for the past three weeks. However, the Corps said it will cut in half the discharge rate heading into the St. Lucie River estuary in an effort to accommodate oyster spawning.

Typically, oysters in the St. Lucie River spawn in March and April.

Beginning Saturday, the Corps will reduce the flows to the St. Lucie River estuary down to an average seven-day pulse release of 250 cubic feet per second, or 161 million gallons per day, as measured at the St. Lucie Lock and Dam. Since Feb. 23, discharges have been flowing at an average rate of 500 cubic feet per second, or 323 million gallons per day.

The Corps said it will maintain the current pulse release to the Caloosahatchee River estuary at a seven-day average rate of 1,800 cubic feet per second, or 1.16 billion gallons per day, from the W.P. Franklin Lock and Dam.

More:Keep track of Lake Okeechobee discharges to the St. Lucie River and the lake's elevation

Heading south

Col. Andrew Kelly, Jacksonville District commander, said over the past seven days, 61 percent of the water taken off Lake Okeechobee has actually flowed south, instead of east and west. Kelly said water has been moving through the Miami Canal, Hillsboro Canal and New River Canal as well as the L-8 near Canal Point. Much of the water is being used for irrigation needs by farmers in the Everglades Agricultural Area while some of it is also going to South Florida Water Management District controlled water conservation areas and stormwater treatment areas. Corps spokesman John Campbell said for the past seven days, an average of 1.9 billion gallons per day has flowed south out of the lake.

Kelly said lowering the lake was a "responsible decision" to help alleviate the need for discharges during the summer, when cyanobacteria has bloomed on lake waters, and to reduce the risk of having to begin discharges in the interest of dam safety. 

This decision will be reviewed again next week, Kelly said. Additional runoff from rain in the Caloosahatchee and St. Lucie basins occasionally could result in flows that exceed one or both targets.

"Our strategy to reverse the rise of the lake has been successful so far," said Kelly. "We've been able to bring the lake down more than a half-foot over the past three weeks. We're going to continue our current pulse release to the Caloosahatchee while making a slight adjustment to the St. Lucie release to help with oyster spawning in the estuary.

"An additional two to three inches of rain is forecast, which will increase the runoff in area canals. Should the rain develop as forecast, we will have difficulty in taking the lake lower, so we want to continue releasing water while the opportunity remains."

Bulls-eye

Kelly says the Corps doesn't intend to drive the water level to a specific measurement.

"I'm not shooting for a target," he said.

According to the Lake Okeechobee Regulation Schedule 2008, the Corps attempts to get the lake level down to 12.5 feet by June 1 in preparation for the start of the hurricane season and rainy season. It manages the lake level throughout the rainy season, which ends Nov. 30, trying to keep it below 15.5 feet by that date. 

Thursday's Lake Okeechobee stage was 12.33 feet above sea level, which is within the operational range that directs Corps decision-making. During the past week, lake levels were reduced by about 3 inches, with an overall 4.3-inch reduction in the past 30 days. The Corps will continue to monitor conditions and adjust flows as necessary.

Last week, Mark Perry, executive director of Florida Oceanographic Society in Stuart, said the discharges need to end soon to preserve the best environment for oysters to spawn. Oysters are critical to estuary health. One adult oyster can filter 50 gallons of clean water a day.

More:If Army Corps stops Lake Okeechobee discharges soon, St. Lucie River suffers little harm

Last week, Florida Oceanographic Society gave the river's overall water quality a "B," or "good," grade but gave an "F" to the river's South Fork, where discharged Lake O water enters the estuary.

Low salinity and poor visibility were the main reasons in the poor grade. The step-down in discharges may help the quality of the water there, Perry said.

Water west

As for the Caloosahatchee River, Kelly said the rate has not been deemed harmful yet based on feedback the Corps has received from residents on the west coast. 

"Typically, when the lake is at 12.3 feet before June 1, we only have a discharge rate of about 1,000 cubic feet per second," he said. "Three weeks ago we, upped that to 1,800 cfs, and while it is a little more than they would like, we have had some good support for it." 

More:SFWMD board to pay Orlando-Fort Lauderdale law firm up to $500,000 in C-44 project lawsuit

Kelly did not confirm the decision to lower the lake, nor the decision to cut back on discharges to the St. Lucie River, was in response to comments from Rep. Brian Mast, a Palm City Republican.

"We have received the message loud and clear that the St. Lucie River area wants zero discharges," he said.

When asked whether drought concerns for communities in Palm Beach County would prompt the Corps to halt discharges completely to hold more water, Kelly replied: "At this time, we have no concerns about water supply."

More:New contractor: Caloosahatchee River reservoir ready in five years

Fishing suffers

The reduction in discharges to the St. Lucie River was welcome news to Palm City angler and boat salesman Bob Chew. He said his fishing trips with son A.J., 15, in the St. Lucie River's South Fork over the past three weeks have been completely unproductive.

"We fish with one of using a topwater plug and the other using a jig to cover the water column, and we haven't had a single bite in two trips," Chew said. "The water clarity has been like mud. You can't see two inches into the water."

Chew said he welcomes any rate reduction by the Corps, but holds back from showering the Corps' commander with praise for his decisions.

"Any reduction will lead to improvement," Chew said. "As for discharging now instead of during the summer, basically he is using a crystal ball as scientific guesswork and playing the odds trying to guess if we're going to have 'x' amount of rain during the rainy season. We all know how predicting weather can be. He could be totally right, or he could wind up being totally wrong." 

For the sake of residents and businesses along the Caloosahatchee and St. Lucie estuaries, they hope he is right.

For more information about the decision, go to the Army Corps of Engineers Jacksonville District website. 

By the numbers

Since the discharges started Feb. 23:

• 6.8 billion gallons: Total amount of Lake Okeechobee water discharged to the St. Lucie River at rate of 323 million gallons a day.
• Half an inch: Approximate amount discharges to the St. Lucie River contributed to lowering the lake.
• From 18 to 5 parts per thousand: Drop in salinity in the South Fork of the St. Lucie River.

Sources: Army Corps of Engineers, Florida Oceanographic Society, U.S. Geological Survey

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