Dec 23, 2020

University Study Shows Restoring Wetlands Near Farms Would Reduce Water Pollution

Researchers from the University of Illinois Chicago and the University of Waterloo studied runoff and high levels of nitrate in bodies of water.


Researchers from the University of Illinois Chicago and the University of Waterloo evaluated the relationship between runoff and high levels of nitrate in various bodies of water.

According to the study, runoff from fertilizer and manure application in agricultural regions has led to high levels of nitrate in groundwater, rivers, and coastal areas, reported The high nitrate levels can threaten drinking water safety and lead to problems with algal blooms, ultimately degrading aquatic ecosystems.

The researchers used maps of remaining wetlands across the U.S. After identifying the amount of nitrate that is currently being removed by wetlands, the results suggest that nitrate loads in the Mississippi River might be approximately 50% higher than they are currently without the presence of wetlands.

The study examined the positive effects of wetlands on water quality and the potential for using wetland restoration. Wetland restoration may be able to improve water quality particularly in the Mississippi River Basin and Gulf of Mexico regions, according to the researchers. 

Their study covers the U.S. and their findings were published in a paper featured in the journal Nature.

"Unfortunately, most wetlands that originally existed in the U.S. have been drained or destroyed to make way for agriculture or urban development. Ironically, areas with the biggest nitrate problems, due to agriculture and intensive use of nitrogen fertilizers, are also usually areas with the fewest numbers of remaining wetlands," said Kimberly Van Meter, UIC assistant professor of earth and environmental sciences and co-lead author of the paper.

According to, previous research has shown that wetlands improve water quality. 

The wetland has a purifying effect, impacting nitrate-laden water and ultimately removing the nitrate from the water. This allows cleaner water to flow.

The researchers also carried out computer model simulations to simulate how wetland restoration can benefit water quality.

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