The South Florida Water Management District is using all of the tools in the box to deal with the runoff from May’s record-breaking rainfall.
“Water levels throughout the district — which is made up of 16 counties in South Florida — are very high after record-breaking rainfall in May,” SFWMD spokesman Randy Smith said at a news conference in West Palm Beach on Friday.
Lake Okeechobee has risen to the level that the U.S. Army Corps of Engineers instituted discharges to the Caloosahatchee and St. Lucie estuaries on June 1, he continued.
“We know there is not a silver bullet,” he said. “There is not one single solution that will stop releases from Lake Okeechobee, but over the long term the district is making steady progress on ecosystem restoration projects that will reduce the need for these harmful releases in the future.”
“Water managers here at the district are looking for operational refinements to move more water from Lake Okeechobee south instead of having it going east and west to the estuaries,” he said. “We are working closely with our state and our federal partners, the U.S. Army Corps of Engineers, the Department of the Interior and the Florida Fish and Wildlife Conservation Commission.
“We’re looking for any and all flexibility within the regional water management system,” he said.
“It’s unfortunate the releases are being made so early in the wet season,” said SFWMD Chief Engineer John Mitnik.
“The decision has not been made lightly.
“This is the third year in a row that Mother Nature has dealt us a bad hand,” he said, “May brought us 300 percent of normal rainfall. It actually set a record for the month of May over the past four weeks.”
He said the district has asked the Department of the Interior for permission to open all of the S-12 water control structures to move more water out of Water Conservation Area 3-A into Everglades National Park.
“We have asked them to raise the operating level of the L-29 Canal near the Tamiami Trail,” he added.
“We have asked for the construction that is currently going on in the south part of the system to be wrapped up.
“All of this is being done so we can send more water south,” he said.
The Tamiami Trail from Tampa to Miami acts as a dam, bisecting the Everglades from coast to coast. The S-12 water control structures send water under the trail to Everglades National Park. Since the rainy season started, two of the structures, the S-12A and S-12B, have been closed to protect the nesting grounds of the Cape Sable sea sparrow, an endangered species. The SFWMD cannot move water through those structures without the consent of the Department of the Interior. Under current policy, the structures must stay closed until July 15.
Opening the S-12A and S-12B structures would double the flow south, according to Mr. Smith. “A and B combined is an additional 800-1,000 cfs. Opening these two triggers other possible structure openings to allow even more flow south,” he explained.
Mr. Mitnik said the district continues to move forward with projects such as the C-43 and C-44 reservoirs and the Lake Hicpochee storage project, as well as the Everglades Agricultural Area reservoir. They also want to develop a well injection program for Lake Okeechobee.
Deep well injection would send excess water down into the boulder zone, in effect sending it to tide by going straight down instead of east or west. Just as with water sent to tide through the estuaries, this freshwater could not be recovered for later use, but using deep well injection could help save the estuaries from the damage of harmful excess freshwater discharges.
“We’re also coordinating with landowners to hold as much water as they can for as long as they can,” he added.
“We have many efforts to remedy the unintended consequences of the Central and Southern Flood Control system,” explained Ava Valdez, Everglades Policy Division director.
“We have well-established partnerships with ranchers as well as citrus growers in the Lake Okeechobee Watershed, the St. Lucie Watershed as well as the Caloosahatchee,” she continued. Some projects are passive in that they hold water back from ever reaching the lake or the estuaries. Others are active, in that they pump water onto their own property and hold it there.
These partnerships create about 54,000 acre-feet of storage, she said. This storage is at about 75 percent capacity as the result of the May rains. The partnerships will be operational throughout the wet season, she said. Terrie Bates, Water Resources Division director, addressed the concerns about reports of algae blooms in the lake and other bodies of water. She said most of the freshwater runoff in the coastal estuaries came from the local basins, which received heavy rainfall in May, before the lake releases started. About a half-million acres discharges through C-43 watershed on the west coast to the estuaries, she explained.
In April and early May, some lake water was released to the Caloosahatchee River to benefit that system, because there wasn’t enough rainfall to maintain the desired salinity balances. When the rains started in May, those lake releases stopped.
From May 29 to June 4, the estuaries received an average flow of 3,654 cubic feet per second (cfs) from the local basin and an average of 1,901 cfs from the lake, she explained. On the east coast, the story is similar. “There are multiple basins that all drain to the estuary regardless of what comes from Okeechobee,” she said.
The tremendous amount of discharge from the local basins coming in turned that estuary’s salinity to completely fresh even before the lake releases started.
“Proportionally, the impact of the discharges coming from the lake is comparatively small,” she said. “Blue-green algae blooms are on everyone’s minds,” she continued. The television news stations are showing images of the 2016 algae blooms. “That’s not what we have out there today,” she added.
The Florida Department of Environmental Regulation samples and tests algae blooms, she said. So far two small blooms have shown “very, very low levels of toxins” — less than 1 part per billion. (Levels over 10 parts per billion are considered a health concern, according to the World Health Organization.)
“Even though you may be seeing visible blue-green algae, it’s not always toxic,” she explained. The district is continuing to sample water across Lake Okeechobee, she said.
Hurricane Irma caused numerous problems across the lake in regards to nutrient level and turbidity, Ms. Bates said.
Using satellite images, they monitor the conditions on the Big O.
She said they have very clear images of Lake Okeechobee. “We really are not seeing any bloom conditions across the lake in June.”
“We’ve got a long, hot summer to get through,” she warned,
“There is no crystal ball to tell us if there is going to be a bloom or not.”
Concentrations of algae along the shoreline do not mean there is a bloom, she added, because algae is buoyant and the wind will cause it to accumulate along the shore.