Posted on November 7, 2023
Dredging up the past can get messy — and costly — especially in the Indian River Lagoon.
So as the price and time to get muck out from the Grand Canal area mounts, so do questions about the calculus of future environmental dredging efforts.
Dredging in Florida coastal waters typically just deepens channels. Waterfront property values soar as a result, economists say. But the Grand Canal and other lagoon dredging projects were sold with a different means to make homes worth more: improve water quality.
There are a few skeptics, but lately the dredge vacuuming up decades of dead, rotted plants from these clouded waters has delivered a few hints of hope — an occasional splash of baitfish or birds. But as the $27 million project inches along, some wonder how much all this dredging is truly doing to heal the estuary.
“Where’s the wildlife? We don’t see anything,” said Ayn Samuelson, president of the of the South Patrick Shores Residents Association. Despite concern over the scant wildlife thus far, Samuelson is quick to add that she and her association support the Grand Canal project and that the county and dredging company have made good-faith efforts to manage a large, complex project. “Sometimes you don’t know what you’re going to get,” she said.
What they’re getting, as with many complex projects, county officials say, is unforeseen snags. Chief among them: COVID, bad weather and a change in the treatment process of the muck water.
From the onset of the county’s $586 million, 10-year half-cent sales tax to clean up the Indian River Lagoon, scientist urged public patience and now assure more proof is coming on the environmental merits of lagoon dredging. Florida Institute of Technology got $3.8 million in state funding to study the concept and has been the primary champion of environmental muck dredging, based on decades of their research.
But as the slow slog of muck dredging drags on, so does the noise, odor and uncertainty of ecological outcomes along Grand Canal and several other areas Brevard plans to dredge, some critics of lagoon spending say.
Not a panacea
The lagoon has been dying for decades. Scientists say the reason is that too many people live too close to the waterway, which doesn’t mix much with the ocean. So all the usual suspects that kill estuaries elsewhere — nutrients from old septic tanks, overfertilizing, sewage spills seeping into the water — are ecologically amplified here.
Those are the reasons why excess algae grew, died and settled on the bottom. Dredging out those dead plant bodies is expected to help by removing sediment that clouds the water to the extent that sunlight can’t reach seagrass to photosynthesize. Seagrass is the ecological linchpin of the lagoon. Manatees eat it and most marine life relies upon it.
Scientists never sold dredging as a lagoon cure-all but long touted it as a ‘low-hanging fruit’ solution in response to an ecological crisis that took decades to unfold. That crisis reached critical mass in 2011, with widespread algal blooms, die-offs of seagrass, fish and manatees in subsequent years.
Money for the Grand Canal project is from the half-cent sales tax voters OK’d in 2016, coupled with state funding. There are several other dredging projects in the works, to the tune of $113.6 million in muck dredging over 10 years.
But as grassroots efforts grow to either renew or double the lagoon tax to grow back seagrass, the Grand Canal project periodically dredges up an ongoing debate over how best to spend that money and whether the dredges will deliver as promised.
How much should we spend on dredging?
Dredging the Grand Canal, the waterway separating Lansing, Tortoise and Samsons islands from the main body of the barrier island, wasn’t in the original lagoon plan. It was one of the muck dredging sites selected in 2014 when, in response to severe algae outbreaks and unusual die-offs of marine life, the Legislature provided money to remove muck from the lagoon.
Sites were selected based on readily available data at the time, county officials said, before FIT mapped and sampled muck hotspots countywide. Since then, FIT has verified high nutrient “fluxes” from that area, county officials said.
Brevard selects potential muck removal projects based on the nutrients released from the muck into the water as well as logistics such as land available for dewatering the dredged material, county officials said.
Poor circulation in the Grand Canal area makes it prone to muck buildup, fluxes of nutrients from that muck, low oxygen levels in the water, fish kills and poor water quality overall compared to other areas of the lagoon. Removing the muck helps prevent it from spilling out into nearby healthy regions of the Banana River after strong wind or rains.
As their canals deepen for the boats, few in South Patrick Shores are complaining.
Those in Samuelson’s association are more worried about local overdevelopment and the accompanying grass clippings, fertilizer and other lagoon pollution that brings. “I think everybody is concerned,” Samuelson said of development pressure in the area.
Meanwhile, the nonprofit Brevard Indian River Lagoon Coalition, leading the campaign to continue Brevard’s lagoon tax, plans a survey of voters on whether to keep the tax and discussing whether to include asking if they’re willing to increase it, a prospect sure to bring muck dredging under the microscope. “it has not been decided what the survey is going to ask for.”
“I think this is a misuse of funds because this is maintenance and not infrastructure,” said Sandra Sullivan, a South Patrick Shores resident and former County Commission candidate in 2022. She’s obtained voluminous documents via public records requests regarding the Grand Canal dredging and other lagoon projects. She calls the sales tax that funds the lagoon program “the muck tax.”
She and Susan Hodgers, a former member of the citizens oversight committee on lagoon tax spending, have been the most vocal critics of the Grand Canal project, and muck dredging in general.
They say too much of the lagoon tax goes to dredging, instead of sewer and septic-tank projects, and point to years of research at FAU-Harbor Branch Oceanographic Institute in Fort Pierce to bolster that stance.
They also say the lagoon program’s Citizen Oversight Committee often lacks enough information to adjust the plan as dredging project details on muck and nutrient removal change.
“In my opinion, it’s not the answer,” Hodgers said. “Our local legislative delegation knows that it’s a welfare program for wealthy residential property owners along the barrier island canals,” she added, “where expensive navigation dredging projects have been disguised as ecological restoration projects to restore the IRL (Indian River Lagoon).”
How much is spent on dredging?
Brevard now spends 37% of the lagoon tax on muck dredging and treating the water released back to the lagoon during dredging, according to its most recent plan, a cost that was about two-thirds of the dedicated lagoon-tax spending in the first few years of the program.
Overall, the county plans to spend $113.6 million in muck dredging over 10 years and $47 million to treat the water that flows back to the lagoon during the process, according to the lagoon plan.
But as dredging projects such as Grand Canal hit delays and unforeseen change orders, that complicates cost comparisons to other countermeasures, such as the lagoon plan’s $66 million in stormwater projects to prevent nutrients from flowing to the lagoon in the first place. And stormwater projects, while a key piece, do nothing to remove the nutrients already in the lagoon.
More muck, more money
If all went as planned, the estimated $26.4 million Grand Canal project was to deliver deeper, cleaner canals by November 2022. Gator Dredging of Clearwater was expected to remove almost 479,000 cubic yards — enough organic gunk to fill 125 Olympic-sized swimming pools — from Grand Canal, entrance canals and more than a dozen residential finger canals south of Pineda Causeway. Then COVID caused delays in the truckers available to haul off the muck and the amount of muck the contractor encountered was 25-35% more than expected.
Now, the project is almost $1 million over budget and won’t be finished until at least mid 2024.
Where does the money come from?
In an email response to Sullivan, Virginia Barker, director of the county’s Natural Resources Management Department, said the total for the county’s portion of the Grand Canal project is $18 million, from the county’s local sales tax, and state grants funded the $9 million balance. Through mid-June, change orders put the project $838,172 over the original $26.4 million contract sum, she added.
“It’s hard to estimate a muck dredging project scope of work and costs,” Duane De Freese, executive director of the Indian River Lagoon National Estuary Program, said via email. “Often the estimated volume of muck may differ from the actual dredged volume.”
But the “reality check” for all lagoon projects, he added, is that costs have increased with inflation, shortages in the supply chain and of qualified contractors.
What’s muck and how much is in the lagoon?
FIT research dating back more than a decade estimated 5 million to 7 million cubic yards of organic muck blanketed the lagoon bottom in Brevard, the legacy of more than a half-century of runoff and erosion.
Muck is mostly soil from construction sites, farms and homes along the lagoon’s tributaries. But grass clippings, algae and other plants also contribute, as do past decades of fertilizer and sewage entering the lagoon. Those nutrients feed too much algae and other plants. When the plants die, they settle on the lagoon bottom as noxious organic muck. When stirred up, muck blocks sunlight to seagrass — a vital barometer of ecological health. And the flux of nutrients — nitrogen and phosphorus — fuels further algae growth.
Each severe storm pushes muck from lagoon canals, fanning out over seagrass beds, eventually killing the grass that manatees and other marine life need to survive. “Often people forget that muck deposits can contribute to high levels of hydrogen sulfide production and low dissolved oxygen levels,” De Freese said. Hydrogen sulfide is a toxic gas emitted when bacteria break down organic matter in low-oxygen environments.
“No single intervention is the ‘silver bullet’ solution,” De Freese added.
Reducing nitrogen and phosphorus from all sources, including muck and control of stormwater to decrease drastic dips in salt levels, should reduce harmful algal bloom frequency, intensity and size, he added, which will support seagrass recovery.
The dredging and water treatment within the Grand Canal project will remove an estimated 2.7 million pounds of nitrogen and 590,000 pounds of phosphorus, said Abbey Gering, associate environmental specialists for the county.
Where does the muck wind up?
County officials say the Grand Canal dredging project won’t shift the burden of past pollution from the lagoon to land.
Workers sample muck at the dredge site to determine the proper destination — either as a fertilizer on farmlands or as waste to a lined landfill for the muck that tests higher for contaminants.
Trucks haul the dried muck to spread on pasture land at Platt Ranch, on the south side of U.S. 192, west of Interstate 95, where the muck is tilled into the ground as fertilizer. Those pastures lie along the floodplains of the St. Johns River, a main source of drinking water for Melbourne, Cocoa and other city utilities along its northerly flow.
Some day, much of the 6.2-square-mile ranch — which measures nearly twice the size of Patrick Space Force Base — could be converted into neighborhoods containing more than 4,600 new homes.
A secondary muck disposal site for the Grand Canal project also is proposed on other nearby farmlands.
The dredge delayed removing muck from a few canals in the Grand Canal area because of high arsenic levels. That and other more contaminated muck likely will go to the JED landfill in Osceola County, permitting documents show.
How does the process work?
The muck gets pumped from onsite sand-separation basins into the large dewatering plastic bags where it stays for a few days to dry. The bags keep the muck contained but let nutrient-rich water flow through, to make its way to a water-treatment basin where it’s treated with a polymer to remove the nutrients before the water is put back into the lagoon.
The dredge slogs on
On this recent sunny October day, a few leaping mullet slap the canal’s surface. That’s been a rare sight in these parts in recent years, local residents say. They’ve became more accustomed to toxic algae and floating dead fish. Then the canals, like the rest of the lagoon, went silent.
Now, residents mostly hear the diesel rattle of a dredge.
It’s too soon to tell exactly what ecological bang for the buck that dredge and others will deliver, lagoon officials say. But in general, muck dredging is an essential part of improving lagoon water quality, and Grand Canal is just a start.
“Once an estuary reaches a tipping point it takes time to reverse the downward trend,” De Freese said. “We are at the very beginning of that restoration process.”