Illinois Central College may soon introduce floating wetlands to study a new way to stymie fertilizer runoff into waterways
Illinois Central College could become one of the first institutions of higher learning in the country to study "floating wetlands" and their impact on nutrient runoff.
It's a problem that ICC professor Pete Fandel has long tangled with. He's been conducting various nutrient runoff reduction experiments on the college's East Peoria campus for years - ranging from testing out cover crops to construction of bioreactors.
The problem Fandel is fighting is fairly straightforward. When it rains, fertilizers containing nutrients like phosphorus and nitrogen are carried by water from lawns and farm fields into creeks and streams. Ultimately, that water will run to the Illinois River, then the Mississippi, eventually ending up in the Gulf of Mexico - with the nutrients still in tow.
When freshwater mixes with salt water, the less dense freshwater will float on top. When that freshwater is filled with nutrients, it triggers algae overgrowth, which ultimately sucks oxygen out of the water.
"There's not enough oxygen for things like shrimp or shellfish, you know, lobsters, things like that to survive, because the oxygen content is too low," Fandel said.
While hypoxic zones are a natural phenomenon at any point where freshwater meets sea water, Fandel said fertilizers exacerbate the effect far beyond its natural impact.
The state has made nutrient loss reduction a priority. The 2021 Illinois biennial report on nutrient loss reduction strategies found that while some progress has been made, more can be done.
ICC is part of an 11-institution consortium applying for a reclamation research grant from the U.S. Department of Agriculture. Fandel said ICC will test out the floating wetland concept near the future site of the $12 million Workforce Sustainability Center. An existing large retention pond on site collects stormwater from most of the East Peoria campus, including the tillable farm acreage.
"That pond gets a lot of nutrients added to it. And obviously, when the water leaves the pond, eventually just like everything else, it's going to the Illinois River," Fandel said. "And so there's a new concept of using what's called a floating wetland, where you actually build a floating mat on top of the pond. You have vegetation growing on that mat. And obviously those live plants are sucking nutrients out of that pond water."
Fandel said a scientific study would assess the percentage of nutrients removed from the water by the wetland plants. That data would ultimately go to the Natural Resource Conservation Service, which would compile a cost-benefit analysis on floating wetlands for potential broader usage, such as in farm retention ponds.
Fandel said it could end up being a win-win for both landowners and nature.
"It's a win for the environment, obviously. Less nutrients leave and get to the river, you have less problems," Fandel said. "And obviously, if that fertilizer stays where it's intended to be on whoever's property it is, you're going to get more of the benefit of what you intended out of that fertilizer."
Fandel said ICC will find out if it is receiving the federal grant sometime next month. If approved, he said they would spend the winter months prepping, and roll out the floating mats sometime after the 2022 spring thaw. Plants may begin to grow the following year.
By year two, Fandel said tangible data should begin coming in to assess performance.