February 23, 2022 – Ames, IA – Dr. Brian Gelder and Dr. Richard Cruse, in partnership with faculty from the University of Missouri, University of Nebraska Lincoln, and Kansas State University, were awarded funds from the US Department of Agriculture (USDA) to map ephemeral gullies and better understand their formation.

This project titled, “A Regional Assessment of High Risk Areas for Ephemeral Gully Formation,” will assess gully formation susceptibility on cropland in Iowa, Kansas, Missouri, and Nebraska. Ephemeral gullies are natural drainageways that repeatedly form in the same location after water runoff events. These states are dominated by row crop agriculture where ephemeral gullies are a common threat to soil and water resources. Soil erosion occurring in these gullies contributes to excess nutrients to downstream waterways.

“Ephemeral gullies play a significant role in soil movement and loss within the Midwest,” said Dr. Brian Gelder, Adjunct Assistant Professor and Manager Research in Agricultural and Biosystems Engineering at ISU. “Using geospatial technology is an innovative approach to better understand management and weather impacts on the soil.”

The work conducted for this study is under the umbrella of the Daily Erosion Project, a program administered by the Iowa Water Center on the ISU campus. Gelder and Cruse will use their expertise from work with the Daily Erosion Project to analyze elevation data and develop numerous models to describe the likelihood of gully formation at every location in a sample of watersheds within the study area. Collaborators at the University of Missouri will identify ephemeral gullies in the landscape to inform modeling calculations. These data will then be analyzed together to determine which models and threshold values can most accurately predict the potential occurrence of ephemeral gullies. Some of the products of this study include a map of ephemeral gully risk and a validated approach to calculate gully risk for the four-state region.

Following this study, the next steps for project collaborators will be to understand how rainfall, soils, and land management and conservation practices interact to affect the risk of ephemeral gully formation. This next phase will begin in late 2023.


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, hbates@iastate.edu