By Tyler Treadway of the TCPalm
FORT PIERCE — Algae blooms aren’t just the result of pollution in the St. Lucie River and Indian River Lagoon; they’re a cause. 
Kilroy water quality monitors deployed by the Ocean Research & Conservation Association indicate that algae from canals and creeks is “a significant source” of nutrients, muck and toxins in the Florida’s east coast estuaries, said Edith “Edie” Widder, ORCA’s lead scientist and CEO.
“It’s a different problem than we’ve always thought we had in the lagoon,” Widder said. “Right now it’s a hypothesis, but we think it’s a pretty good one.”
If ORCA’s finding is correct, measures to clean the estuaries need to change drastically, she said. The good news is getting rid of algae should be easier while it’s still in relatively small canals than after it’s in the much larger lagoon, she added.
The traditional view of how the estuaries get polluted goes like this:
High levels of nutrients — primarily nitrogen and phosphorus — flow from creeks and canals into the estuaries, spawning algae blooms in the slightly salty water. The slimy, pea-green blooms shade and kill sea grass beds.
ORCA’s theory goes like this:
Nitrogen and phosphorus cause freshwater algae to build up in the canals and creeks leading into the St. Lucie River and Indian River Lagoon. The nutrients aren’t detected because they’re inside the algae. When the algae hits the slightly salty water of the estuaries, it dies. That releases the nutrients and toxins within the algae into the estuary, and the dead algae cells fall to the bottom of the water as muck.
In this theory, damage is done to the estuaries even when there aren’t bright green blooms covering large portions of the estuary.
Data From Kilroys
ORCA scientists developed the theory by studying algae readings from Kilroys in the C-24 Canal, a tributary of the St. Lucie River where they are conducting research sponsored by the Scotts Miracle-Gro fertilizer company.
State-sponsored Kilroys deployed at the mouths of creeks and canals along the lagoon also showed significant periodic accumulations of algae. The only Kilroys that didn’t follow the pattern were on Hutchinson Island, where there are no long creeks or canals.
Ongoing measures to clean Florida’s estuaries, such as the state Department of Environmental Protection’s Basin Management Action Plans, are based on monitoring nitrogen and phosphorus. They don’t see those nutrients “hiding” in algae, Widder said.
“We need to be looking at all the algae entering the estuaries, as well as the nutrients if we’re going to understand what’s really harming our water,” Widder said.
Next Steps
Widder said the findings lead ORCA to two next steps.
One is finding where the nitrogen and phosphorus that feed freshwater algae are coming from.
Boyd E. Gunsalus, an environmental scientist with the South Florida Water Management District and member of an oversight panel keeping track of the Scotts study, said researchers have identified several “hot spots” with high nutrient levels where some creeks and smaller canals drain into the C-24. Putting Kilroys at the mouths of those creeks and ditches will help determine individual groves and fields with high-nutrient runoff.
“The ultimate goal is to stop nutrients at the source,” Widder said. “Pointing fingers is usually counterproductive; but hopefully we can convince farmers they’re wasting money by putting too much fertilizer on their fields.”
The other is to figure a way to stop algae in creeks and canals before it enters the estuaries.
The bad news is that algae cells are too small to filter out of the water.
The good news, according to Indian River County Commissioner Peter O’Bryan, a member of the oversight committee, “It could be that removing algae from the canals will be easier than removing nitrogen once it hits the estuary.”
More Research, More Money
The 25 Kilroy water monitors in the lagoon are paid for by a state contract set to run out in March. ORCA Managing Director Warren Falls said the Fort Pierce-based nonprofit will ask the 2016 Florida Legislature for $750,000 in January to continue the program.
Scotts gave ORCA $625,000 for the study to pinpoint the sources of pollution entering the St. Lucie River via the C-24 Canal. Falls said that money will run out in about six months.
“We haven’t approached Scotts for more money, yet,” he said, “but that’s the plan.”
ORCA’S FINDINGS
Here’s what you need to know about preliminary findings of the Ocean Research and Conservation Association’s study sponsored by Scotts Miracle-Gro:
Kilroy water monitors found that algae built up in creeks and canals is a significant source of nutrients, muck and toxins in the St. Lucie River and Indian River Lagoon.
The finding was confirmed by state-sponsored Kilroys elsewhere in the lagoon and in separate lab testing.
If ORCA’s hypothesis is true, Basin Management Action Plans that currently work toward reducing nitrogen and phosphorus need to consider algae, too.
Getting rid of the algae in the relatively small creeks and canals should be easier than when it reaches the lagoon.
ORCA’s next steps include figuring out how to do that, and pinpointing the sources of the nitrogen and phosphorus feeding the algae.
OVERSIGHT PANEL
Donald Albrey Arrington, executive director, Loxahatchee River Environmental Control District
Deborah Drum, manager, Martin County ecosystem restoration and management
Boyd E. Gunsalus, lead environmental scientist, Okeechobee Service Center, South Florida Water Management District
Peter D. O’Bryan, Indian River County commissioner
Mark Perry, executive director, Florida Oceanographic Society, Stuart
H.M. Ridgely, real estate manager, Evans Properties Inc.
About Tyler Treadway
Tyler is an environmental and lead Indian River Lagoon reporter at Treasure Coast Newspapers.
@tcpalmtreadway tyler.treadway@tcpalm.com 772-221-4219