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Florida’s ecosystems strained after Irma

By Staff | Nov 21, 2017

Florida’s Everglades and connected ecosystems are fighting battles on all sides.

Artificial re-routing of Lake Okeechobee overflow from south to east and west, and the extremes in weather patterns are straining the delicate and complicate systems in southern Florida.

The Sanibel-Captiva Conservation Foundation held a panel discussion Tuesday, Nov. 14, to update the community on water conditions in the local estuary and watershed system, as well as talk about the in-the-works steps to address issues in the Everglades.

The issues are all connected: A dike had been built in the 1920s around Lake Okeechobee and more had been added in 1947, after a hurricane caused severe flooding in southwest Florida. Then state and federal government began the Central and South Florida Flood Control Project, working to protect development from the river of grass. The Caloosahatchee and St. Lucie Rivers became the recipients of excess water in the lake. The rivers were also altered to help form the Okeechobee Waterway, a federal commercial route through the center of the state. The Caloosahatchee was expanded, deepened and renamed the C-43 canal, and locks were installed to engineer the flow of the river.

“It’s not even called a river,” said Eric Milbrandt, director of the marine lab at SCCF.

Fast forward to this year, and the lake, rivers, and connected ecosystems have gone through cycles of suffering. And, with 2016’s intense rains, followed by an intense drought, followed by more rains and then a hurricane, Florida’s had a rough couple years.

“This was an extraordinary year,” said Rae Ann Wessel, director of policy at SCCF.

The local systems have been trying to recover through these extreme variabilities in the season, extremes that could become frequent. And less average in-betweens

“The signature of climate change is having more frequent extremes, like drought and deluge,” she said.

After Hurricane Irma, Lake Okeechobee hit record levels of 17.2 feet, the highest it has been since 2005. The Army Corps of Engineers manages the lake; typically it’s kept between 12.5 and 15.5 feet to protect the Herbert Hoover Dike.

That lead to record releases of fresh water into the Caloosahatchee and out into the Gulf between Sanibel and Estero islands – and SCCF’s research team is already seeing the effects.

Before human engineering altered the ecosystem, the Caloosahatchee started mixing with tidal saltwater more than 40 miles upstream. Now, the Franklin Lock cuts off that natural ebb and flow and the mixing occurs closer to the mouth of the river. Wessel said this mixing area is important because it creates a nursery for a myriad of species. However, the flood of freshwaters this fall have pushed that mixing zone beyond the mouth.

It’s part of why people have reported seeing “root beer” colored water, or dark water, on the beach. Wessel said it’s typical to see darker colored water in the river around Iona, as the tannin-dyed hue is a signature of the Caloosahatchee. But the dark water now is different. It’s not just tea-colored, it’s opaque.

The dark water now is carrying colored, dissolved organic matter and sediments that are blocking sunlight, and the flush of freshwater from Lake Okeechobee is pushing that dark water out onto the sandy white shores. It’s preventing photosynthesis from occurring in the aquatic plants below, as well as reducing the needed salinity levels.

“We’re seeing sea grasses that are covered in barnacles. I’ve never seen that before,” Milbrandt said. “They’re not growing.”

Milbrandt said the barnacles are an indication that the seagrass is stressed from too much freshwater and dark water, and is now growing too slowly to shed the barnacles.

The aquatic vegetation is dealing with lower oxygen levels in the water, and unlike fish, they can’t just swim away to better waters. That’s why in the weeks following the hurricane, beaches on Sanibel and Fort Myers Beach were seeing a lot of detritus washing up onto the beach.

Florida Bay, the area at the southern tip of the state’s peninsula, is also struggling. It used to be the mouth of the slow-moving river of the Everglades, but as the Everglades have been starved of water, so too has the bay become more and more saline instead of its needed brackish content.

The Everglades were so dry from April to June this year, the peat soil began to crack and burn, said Stephen Davis, a SCCF ecologist. The soil gets so dry, it can oxidize and disappear.

“During the wet years, Florida Bay ekes by,” he said.

Florida Bay serves an important role in the life cycles of much marine life, as it is a nursery for fish and shrimp, which help feed larger predators.

In 2015, the lack of freshwater and a drought lead to fish kills and mangrove and seagrass die-off. The dead materials in the water further reduced the oxygen levels. Davis said the tumultuous rains in 2016 led to a short recovery period, but that rebound was squelched by the following drought. At one point, the salinity levels in Florida Bay measured higher than seawater. Now there are algal blooms visible from satellite imagery drifting from Florida Bay down past the Keys.

This algae material is not necessarily the same type of toxic cyanobacteria that occurred on the east coast in 2016; however, excessive algae in the water causes a multitude of issues for marine life.

“We’re keeping our eyes on this,” Davis said.

A fast-track to progress?

The discolored waters near Sanibel and Fort Myers Beach aren’t going to end overnight. Lake Okeechobee is still releasing water down the rivers at a tremendous speed from the Irma rainfalls, and muddy brown will be the norm for several months. The Army Corps of Engineers announced last week that it would reduce flows beginning Nov. 17 to the Caloosahatchee for the first time since the hurricane. The lake measured 16.62 ft on Nov. 16.

The muddied waters will still probably be the norm off and on for the next several years, but Wessel said help has been expedited.

Despite the many trials the Everglades and Caloosahatchee systems are enduring, there’s a bright side: Senate Bill 10 (SB-10) was passed by Florida in May, which is expediting a plan to build more storage south of Lake Okeechobee in the Everglades Agricultural Area (EAA).

It could still be 10 years before that storage is built, but according to the SCCF panel, that’s fast.

“You’re going to have to fasten your seat belts,” Wessel said. “This is like whip-lash. It’s in high gear.”

The EAA is currently leased out to agricultural companies; however that lease is set to expire in 2019. Rather than waiting, the SB-10 approved beginning now to plan and design to convert the EAA into storage reservoirs, starting first with state-owned lands. Within the EAA are two parcels, A-1 and A-2, which were purchased to host the reservoir. A-1 and A-2 total 31,000 acres.

The idea is to first use up all the state-owned land before approaching willing sellers to aggregate additional storage if needed.

The construction of these storage areas will take about 10 years, if the state can get approval for a 50/50 cost share with the federal government.

“It’s realistically 10 years, maybe less with this aggressive approach,” Davis said.

According to her timeline, by Oct. 1, 2018, Florida must submit a report on the EAA project to the U.S. Congress for approval, and then seek approval for funding, which would hopefully be granted in 2019.

An audience member, David Olmstead of Sanibel, asked if that funding would be a “given” from the federal government.

“Nothing is a given in any governmental body,” Wessel said. “It’s up to us to create the demand for this priority.”

The EAA storage project is only one of many projects already underway as part of the Comprehensive Everglades Restoration Program, a joint effort between the state and federal governments to complete 68 different projects that will help restore the Everglades.

One of those projects includes the C-43 reservoir, a freshwater storage facility for the Caloosahatchee River. It’s underway on the south side of the river near LaBelle, and freshwater can be stored there for timely released during the dry season. While too much freshwater flowing down the Caloosahatchee is a problem, so is too little.

Another, the Picayune Strand restoration near Naples, is nearing completion. A storage basin north of the lake has been design, but construction has not started. The storage reservoir in the north can’t hold as much water as the area south of the lake.

While storage basins will help, they won’t solve the problem, Davis said. He said half of the area that was once the flood zone for Lake Okeechobee’s overflow and the Everglades has been taken by development.

“We can’t store our way out of a flooding event,” he said.

Another important project is converting Alligator Alley, or U.S. 41 between Naples and Miami, from a levy to a bridge. One mile has been completed and 2.6 miles are under construction. Turning the road into a bridge will allow the Everglades to flow freely beneath it.

“These project will open the bottom of the bathtub,” Wessel said.

While the government makes its plans, the weather patterns are uncontrollable. Florida has been experiencing more frequent extremes with shorter periods of average conditions in between.

But, Wessel said, the extremes aren’t foreign to Florida’s ecosystems and some are even beneficial; the burnoff of excess fuel and nutrients from a fire or a drought are essential.

“The ecosystems of South Florida evolved into extreme weather patterns. Hurricanes, fires,” she said. “They can help regenerate.”

The timeline seems long for relief, but getting the EAA reservoirs in 10 years is a lot faster than normal. Wessel said the ecosystems can’t survive with month-to-month extreme swings, and they will need a few years of average conditions to recover. While the Florida native wildlife has evolved to live here, its survival will be a matter of the frequency and durations of these extreme patterns.

Milbrandt said there was no way of predicting if Florida’s ecosystems could hold out for the next 10 years.

“Ecosystems can collapse, but they’re incredibly resilient,” he said. “It’s not that healthy, but we still have seagrass. We really don’t know, and that’s a cause for concern.”