Converted
08-21-2003, 04:04 PM
By Suzanne Wentley staff writer
August 21, 2003
Heavy, continuous releases from Lake Okeechobee are likely to begin Saturday for the first time since 1999, after Hurricane Irene struck, water managers said Wednesday.
For the first time in four years, the lake will today likely reach the level at which water managers abandon "pulse-style" discharges in favor of continuous releases into the St. Lucie Estuary. That level varies according to season.
Pulse releases — which will likely end Friday — mimic natural rainstorms by varying the amount of water flowing into the estuary to limit negative effects.
River activists fear continuous releases will further harm the stressed marine life in local waterways.
Although a formal discussion among scientists with the South Florida Water Management District and the Army Corps of Engineers is scheduled for today, officials from both agencies agreed a constant release of 2,500 cubic feet — or 18,701 gallons — per second will likely flow from the St. Lucie Locks indefinitely.
"We're at a point where there's a real possibility of increased discharges from Lake Okeechobee, beyond the pulse mode we've seen for over a year," said Tommy Strowd, director of water operations for the water management district.
Marine biologists and St. Lucie River advocates said they expect to see fish lesions within 30 to 45 days after constant discharges begin. An outbreak of such lesions stymied the local tourism economy in 1998.
"I'm a little surprised that we haven't seen any (lesions) yet," said Ann Forstchen, a fish health biologist with the Florida Marine Research Institute. "The pulse releases do allow the estuary to recover in between. It's once they start the prolonged releases, where the salinity drops and stays very low for a long period of time, then we'd expect to see an increase in lesions."
Susan Sylvester, a water management specialist with the Army Corps of Engineers in Jacksonville, said engineers today will discuss the rising lake level, the increasing flow into the lake from the Kissimmee River and the above-average rainfall predicted.
Constant releases are "extremely likely," she said.
On Wednesday, Lake Okeechobee stood at 16.02 feet above sea level — less than a quarter of an inch from the level at which water managers can start continuous releases.
However, 130 days of pulse releases this year — along with heavy rainfall runoff — have dropped salinity in the St. Lucie River to critically low levels.
On Aug. 14, the amount of salt in the water dropped to less than one part per thousand at the Roosevelt Bridge, causing severe stress to the oysters, sea grasses and other organisms that rely on salinity in the brackish ecosystem.
Kevin Henderson, executive director of the St. Lucie River Initiative, said activists have been lobbying water managers to keep the lake between 13.5 and 15.5 feet above sea level, but Lake Okeechobee never dropped below 14.5 feet even at the end of the dry season.
"That extra foot, we never got there," he said. "If they had done that with the pulse releases, we would still be in the safe zone."
Henderson said he'll begin the wait for an increase in lesioned fish caught in the inland waters in Martin and St. Lucie counties.
"Why do we have this deja vu all over again?" he said.
August 21, 2003
Heavy, continuous releases from Lake Okeechobee are likely to begin Saturday for the first time since 1999, after Hurricane Irene struck, water managers said Wednesday.
For the first time in four years, the lake will today likely reach the level at which water managers abandon "pulse-style" discharges in favor of continuous releases into the St. Lucie Estuary. That level varies according to season.
Pulse releases — which will likely end Friday — mimic natural rainstorms by varying the amount of water flowing into the estuary to limit negative effects.
River activists fear continuous releases will further harm the stressed marine life in local waterways.
Although a formal discussion among scientists with the South Florida Water Management District and the Army Corps of Engineers is scheduled for today, officials from both agencies agreed a constant release of 2,500 cubic feet — or 18,701 gallons — per second will likely flow from the St. Lucie Locks indefinitely.
"We're at a point where there's a real possibility of increased discharges from Lake Okeechobee, beyond the pulse mode we've seen for over a year," said Tommy Strowd, director of water operations for the water management district.
Marine biologists and St. Lucie River advocates said they expect to see fish lesions within 30 to 45 days after constant discharges begin. An outbreak of such lesions stymied the local tourism economy in 1998.
"I'm a little surprised that we haven't seen any (lesions) yet," said Ann Forstchen, a fish health biologist with the Florida Marine Research Institute. "The pulse releases do allow the estuary to recover in between. It's once they start the prolonged releases, where the salinity drops and stays very low for a long period of time, then we'd expect to see an increase in lesions."
Susan Sylvester, a water management specialist with the Army Corps of Engineers in Jacksonville, said engineers today will discuss the rising lake level, the increasing flow into the lake from the Kissimmee River and the above-average rainfall predicted.
Constant releases are "extremely likely," she said.
On Wednesday, Lake Okeechobee stood at 16.02 feet above sea level — less than a quarter of an inch from the level at which water managers can start continuous releases.
However, 130 days of pulse releases this year — along with heavy rainfall runoff — have dropped salinity in the St. Lucie River to critically low levels.
On Aug. 14, the amount of salt in the water dropped to less than one part per thousand at the Roosevelt Bridge, causing severe stress to the oysters, sea grasses and other organisms that rely on salinity in the brackish ecosystem.
Kevin Henderson, executive director of the St. Lucie River Initiative, said activists have been lobbying water managers to keep the lake between 13.5 and 15.5 feet above sea level, but Lake Okeechobee never dropped below 14.5 feet even at the end of the dry season.
"That extra foot, we never got there," he said. "If they had done that with the pulse releases, we would still be in the safe zone."
Henderson said he'll begin the wait for an increase in lesioned fish caught in the inland waters in Martin and St. Lucie counties.
"Why do we have this deja vu all over again?" he said.