The essence of the idea is simple: pump ocean water into the Indian River Lagoon and create new inlets that would then let the water circulate back to sea, diluting or removing the excess nutrients that are killing the estuary.
But to some scientists who study fish populations, that is not how it will work.
Some critics of the concept say that the plan to study the creation of one or more new small inlets into the Indian River Lagoon to help flush out the waterway, at worst, could negatively change the natural balance of the estuary, and, at best, is a complete waste of time and money.
Fish conservationists in particular warn that a new inlet would risk adversely changing the ecology of the lagoon which is a nursery ground for many species, while pushing the pollution to the southern lagoon, out Sebastian Inlet and onto nearby beaches.
And they say the study itself diverts taxpayer money from solutions that could pay much better long-term ecological dividends.
"You're taking polluted water and trying to clean out other polluted water," said Mitch Roffer, a Melbourne Beach consultant and founder of ROFFS, a scientific consulting company based in Miami and West Melbourne, that uses satellites to help fishermen track fish movements.
State lawmakers recently gave the Florida Institute of Technology almost $1 million toward the concept of creating a small temporary opening to the lagoon so that more ocean water can flow into the estuary and help clean it up.
The idea is that if more ocean water can flow into the lagoon, the cleaner it will be. The money will pay to design and monitor a temporary pipe/pump/inflow system at Port Canaveral near Canaveral Locks. The project would be permitted by the U.S. Army Corps and reviewed by Florida Department of Environmental Protection.
But Roffer and a few other critics of the plan warn there's no "simple, quick fix to the lagoon's pollution problems and that the project diverts money from tackling the root source of the problem, which is stopping the source of excess nutrients entering the lagoon.
According to Aaron Adams, director of science and conservation for the nonprofit Bonefish & Tarpon Trust, based in Miami, FIT's project takes the focus off tried-and-true ways of fixing estuarine pollution problems, such as what's been done in the Tampa Bay, Chesapeake Bay and Narragansett Bay regions. Those areas focused on hooking up homes on septic tanks to sewage systems, runoff reduction and other ways decreasing pollution at its sources, not inlets, he said.
"It gives excuses to policy makers to not invest in the fundamental decisions that have to be made," Adams said.
FIT's project also doesn't consider potential unintended and unpredictable consequences to fish populations like tarpon, which have evolved to spend their larval and juvenile stages in the backwaters of the lagoon, under natural ecological conditions, thousands of years in the making, that humans can hardly expect to mimic.
"If you change the flows, you will change the ecology," Adams said.
"Research money spent on searching for this magical (inlet) solution is a waste of taxpayer resources in dollars and personnel," Roffer added.
But the FIT researchers pursuing the idea say new inlets and/or pipes and pumps that add more seawater are misunderstood and could be one valuable piece to help cure a complex pollution puzzle.
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*We're not trying to stir the sediment," said Austin Fox, assistant professor in FIT's department of ocean engineering and marine science. "What we're trying to do is .. —like (with) your compost pile — if you can't turn it, what you could do is blow a fan over it." By helping turn over the muck will let more oxygen in to make the sediment healthier, Fox says.
But according to Roffer and the others, FIT is using limited field observations, unproven models that lack peer review. "They are effectively siphoning off valued and proven resources to show that flushing the toilet will cure our problems with a little help from the internal Indian River Lagoon’s ecological processes."
Not so, Fox says. Water would flow from the inflow site at the port towards inlets, but along the way, healthier sediments would neutralize or consume nitrogen and phosphorus.
So despite more water moving, potentially less nitrogen and phosphorus would reach the inlets, Fox said. In other words they shouldn’t be 'flushed' into the ocean, he said, but instead nitrogen is processed and removed into the atmosphere and phosphorus would be buried in the sediments.
Fox explains the process as follows:
“Good” bacteria in the lagoon help convert nitrogen from forms readily available to algae into inert nitrogen gas.
Inflow of more ocean water stabilizes dissolved oxygen in the nearby lagoon, restoring healthy conditions along the bottom and nutrient cycling by promoting communities of “good bacteria.”
Breaking low-oxygen cycles promotes uptake of phosphate onto sediment particles, removing it from the water and making phosphate unavailable to algae.
During an algae bloom, seagrass or when other plants die, bacteria rot them and consume oxygen as they decompose the organic muck buildup along the bottom. When there's enough organic matter, bacteria consume so much oxygen that little else nearby can survive.
"If you want to change the lagoon you need to change the bacteria in the lagoon," Fox said.
"By giving the system a nudge in the right direction using strategic inflow of seawater, we hope to promote restoration of these natural processes," Fox wrote.
A seawater inflow system successfully raised oxygen levels in the water in Destin Harbor, Fox said.
FIT chose Port Canaveral as the temporary demonstration site for the pilot project because of the lower cost, the ease of access to the site and the existing exchange of ocean water at the locks, according to a frequently asked questions page about the project on the FIT website.
"It's just to see the magnitude," FIT researcher Gary Zarillo said of the degree to which the project might improve water quality. "It's one small step."
Zarillo has studied the concept of new inlets in the past, including leaving the locks open, hypothetical new tidal inlets, pumping stations and widening of Sebastian Inlet. Those studies have shown that opening Canaveral Lock alone would do little to flush out the lagoon. New tidal inlets, however, and pumping stations linking the ocean across narrow stretches of the barrier island produced water quality improvements.
A narrow tidal inlet or pumping station in the southern Mosquito Lagoon would flush out Mosquito Lagoon and the northern Indian River Lagoon within 70 days or less, a 2015 study by Zarillo showed. and a tidal inlet just north of Patrick Space Force Base would improve flushing of the Banana River.
But to Adams of the Bonefish & Tarpon Trust, new inlets are a fool's errand.
"If you change the flows you will change the ecology," said Adams, who lives in Melbourne Beach. "Basically what they're saying is we need to engineer a new estuary to supposedly fix things. I'd love to have an example where engineers created a new ecologically functioning system.
"They don't consider the socio-political complexities," Adams added.
Adams has heard it all about inlets before. He's not sold.
"We have to realize that others have been through this before. and those places that recovered or are on the way to recovering, gave us really good lessons one what works and what doesn't work," Adams said. "I think the study lacks the rigor on background research before anything like this is even conceptualized."
George Minto, a retired Lockheed Martin aerospace director in Titusville, for years pitched a similar pump-pipe inflow concept to lagoon resource managers. He's proposed an array of small electrical pumps that run continuously, with special inlet gates in the ocean and heavy duty flexible piping buried in the sand over the dunes into the lagoon, pulling an estimated 40 million gallons per month of ocean water into the lagoon.
It wouldn't have to be permanent, Minto said, just until water quality improved enough.
"Of course energy does not come free. FPL may donate the power or the state or some organization may fund the cost of the electrical power. Same goes for the construction efforts to install the pumps and piping etc.
"This initial proposal only addresses the northern IRL. If improvement is obvious then nothing stands in the way of adding this scheme further south," Minto said.
Similar engineering efforts have improved water quality in New York, California, and internationally, according to an FIT writeup about the Brevard study. Since 1992, Destin Harbor pump site in Destin, Florida, also has used a similar concept to increase ocean water circulation to improve water quality and prevent fish kills. said new or wider inlets are not the panacea for curing the lagoon, however.
"There will always be somebody saying we should be doing something different," Fox said. "This is not a silver bullet, but it is one thing in a multifaceted approach that could be a benefit."
This article originally appeared on Florida Today: Lagoon inlets could alter it's ecology and local beaches, critics say