March 16, 2022 – Ames, Iowa – Dr. Greg LeFevre, Assistant Professor, Civil and Environmental Engineering at the University of Iowa, recently completed a study in partnership with the US Geological Survey to determine the impacts of emerging contaminants in wastewater effluent in Coralville, Iowa. Findings from this study reveal potential ecological exposure routes due to the evidence of pharmaceuticals and chemical compounds in streams.

This study, conducted from 2017-2021, sought to understand the presence of chemical compounds within wastewater effluent and the impacts of sustained exposures on life within Iowa streams. An additional objective was for researchers to understand the mixtures of pharmaceutical compounds and the possible impacts a combination of chemicals may have on living organisms within the aquatic environment. Research occurred at Muddy Creek, an effluent dominated stream in Coralville, Iowa. Muddy Creek is heavily influenced by wastewater effluent from the North Liberty, Iowa wastewater treatment facility.

A critical finding in the study was the level of neonicotinoid pesticides found in the wastewater. This can lead to concerns regarding overall water quality, as well as indicate exposure to humans. Wastewater analysis gives researchers and water managers clues as to unanticipated routes to human exposure. In the study, the city has a separate sewer system, and so pesticides in the wastewater indicate usage in the home, as opposed to outdoors, which is a potential public health concern. Further work will be done to communicate this finding to homeowners and real estate managers.

This research was funded by the 104(g) National Competitive Grants Program. The U.S. Geological Survey (USGS) and the National Institutes for Water Resources (NIWR) jointly manage a national competitive grants program(104(g)) to fund research of a regional or interstate nature.

Read the full research findings here.


The Iowa Water Center: The Iowa Water Center is a federally funded organization, part of the National Institutes for Water Resources. Located on the Iowa State University campus, it is one of 54 institutes located throughout the United States and U.S territories. The purpose of the Iowa Water Center is to identify water-related research needs, provide outreach and education opportunities, and disseminate information about Iowa’s water resources to the public to form better policies and everyday practices.

Information contact: Hanna Bates, Iowa Water Center,