LAKE KISSIMMEE -- An innovative water treatment company is taking on the challenge of getting the muck out of a Florida lake.

In 2022, AguaCulture successfully completed a proof-of-concept project on the Indian Prairie Canal to mechanically remove invasive aquatic plants from Lake Okeechobee, liquify them and pump the liquid through a special hose to be spread on pastures as far as 20 miles away.

That project, funded by a grant from Florida Fish and Wildlife Conservation Commission (FWC) proved the concept works.

A new AguaCulture project on private property on the shore of Lake Kissimmee is now proving that same machinery can be adapted to suck some of the muck from the bottom of a lake without creating turbidity.

Eagle Haven Ranch owner Arnie Bellini is funding the project. Bellini, the founder of the Live Wildly Foundation, is interested in large scale conservation projects, explained AguaCulture champion Mike Elfenbein, executive director of the Izaak Walton League Cypress Chapter.

The 3,000-acre ranch was once the site of a 350-home trailer park and was slated for more development. Bellini purchased the ranch to save a piece of wild Florida. The mobile homes are gone, and the land, which includes five different types of natural Florida habitat, is home to more than 200 native species including eagles and Scrub Jays, as well as Florida Cracker horses and cattle.

The ranch has a dispersed water project, to hold excess water from Lake Kissimmee, and is part of the Florida Wildlife Corridor.

Elfenbein said they hope to use the AguaCulture system to improve the soil in different types of native Florida land, improving the habitat for wildlife.

The process combines existing technologies in new ways. Most of the equipment came from junkyards, explained Nick Szabo, AguaCulture owner. The large tank that holds the liquid is repurposed – it was once used to hold manure on an Iowa farm. The machine that grinds up vegetative matter came from a paper mill.

The only new technology is the patented hose, which floats just under the surface of the water. Using a series of booster pumps, the nutrient-rich liquid that comes out of the “Green Mach 1” can be pumped as far as 20 miles away, to be used as a soil amendment.

For the Lake Kissimmee project, instead of using mechanical harvesters to gather plants to dump into the Green Mach 1, a vacuum hose is attached to a floating barge. The vacuum works the same way a swimming pool vacuum works, Szabo explained. It’s positioned about 8 inches off the bottom of the lake, so it doesn’t disturb the lakebed. It sucks up decaying vegetation near the lake bottom. Dredging a lake stirs up muck, releasing more nutrients into the water column, Szabo explained. The vacuum method does not stir up the water. Watching the machine at work, the water above the vacuum device remains clear.

“We don’t want to remove the sand,” Szabo explained, “just the gravy-like muck that is killing the lake.”

This lumpy “gravy” is pumped through the machine to liquify the decaying vegetative matter. This liquid is pumped through the hose to a designated field 5 to 20 miles away where a machine spreads the liquid thinly on the grass, with a volume equal to about 1/16 to 1/8 inch of rainfall.

Removing that mucky layer allows more sunlight to reach the lake bottom, which encourages the growth of natural submerged aquatic vegetation (SAV), Szabo explained. Removing that mucky layer also creates more space for water storage in the lake and improves the dissolved oxygen levels in the water.

“We’re not dredging,” he said. The vacuum slowly sucks up the muck, while the water above it stays clear.

The project has permits from U.S. Army Corps of Engineers, Florida Department of Environmental Protection and FWC.

Szabo said while other companies show computer models or small models of their technology, AguaCulture has a real-life project.

“DEP said we’re the only company out on the water doing something on a large scale,” he added.

“The problem with most projects is they are not scalable,” Szabo said. “This can be scaled.”

How do they know where the phosphorus goes?

The project includes soil and leaf testing to determine the phosphorus levels before and after spraying.

How does the phosphorus leave the watershed?

Grass takes in nutrients such as phosphorus and nitrogen as it grows. When the grass is cut for hay and shipped out of the watershed, those nutrients go with it.

In areas with native vegetation that is not suitable for hay, cattle can eat the vegetation. The cattle turn the nutrients in the plants into flesh and bone. Florida cattle ranches are cow/calf operations.  Once a year the annual crop of cattle (about half the herd) goes to market – taking a lot of phosphorus with them. Those cattle are shipped to the feed lots in the Midwest as it is cheaper to ship the cattle to the grain than to ship the grain to the cattle. The remaining cows have new calves, and the cycle continues.

How can they be sure the phosphorus in the liquid soil amendment won’t be washed back into the lake?

Szabo said the project will monitor the soil and the vegetation to track the nutrients. “We are doing soil and leaf tests before and after,” he said. “We have to show where the nutrients go.” The liquid soil amendment must be applied at the appropriate rates – only what the plants in that section of land can absorb.

“We have to get the muck out of the lake. We need a place to put it,” Szabo said. “We have to make a product people want. If you treat the material like a waste, you get wasteful results.”

Using that muck as a soil amendment to grow hay or to grow forage for cattle turns it into a marketable product, he said. People will buy a bale of hay. They’ll buy a steak.

He said if the muck is removed from the lake but not repurposed, it just creates a problem at another location.

“A project only works if everybody wins,” said Szabo. With AguaCulture, the local community, the taxpayers, wildlife and the government agencies all win, he said.

“It’s the simplest, most cost effective, proven way to clean up the ecosystem,” he said.

“Our future and our health are based on the health of the water,” he said. “If we can put the nutrients back on the land, the land will be more productive.” In addition, healthier grass means less erosion and less nutrient load in runoff when it rains.

Removing the muck from the lake improves the lake’s habitat. He said they have already seen larger fish coming into the areas they have cleaned.

What does it cost?

The AguaCulture process can remove phosphorus from the lake bottom for $150 per pound, said Szabo. The grant process focuses only on phosphorus reduction but there are other benefits, he said. The project will also remove nitrogen and improve the lake ecology.

In comparison, the galvanic cell process used by NuQuatic Advanced Water Technologies near Nubbin Slough has a contract from South Florida Water Management District to remove phosphorus for $312 per pound.