Water quality field day focused on Iowa's karst topography

Iowa State University Extension and Outreach
Farm Forum

AMES, Iowa — Iowa Learning Farms, in partnership with the Iowa Nutrient Research Center and Conservation Learning Group, hosted a free virtual field day on the challenges of improving water quality and quantity management in the karst topography of the Upper Iowa Watershed on Feb. 4.

Presenters include Matt Frana, Upper Iowa Watershed project coordinator, and Winneshiek County landowners Tom and Maren Beard.

“The karst topography in northeast Iowa creates some unique challenges when planning for water detention project sites,” said Frana. “Shallow depth to bedrock, easily dissolvable bedrock, highly fractured bedrock and sinkholes can become problematic if water is pooled above or near them.”

Karst terrain is characterized by the presence of easily dissolved bedrock (limestone and dolomite) near the ground surface, according to the Iowa Department of Natural Resources.

“By reviewing soils, bedrock, sinkhole and terrain GIS map layers, high-risk areas can be identified and avoided without wasting time on lengthy and costly in-field investigations,” said Frana. “Electrical Resistivity Imagery can be used to determine if potentially problematic conditions exist below the surface as part of the planning process to better assure successful projects.”

The field day was recorded and archived on the ILF website so that it can be watched at any time. The archive is available at https://www.iowalearningfarms.org/page/events.

Iowa landowners and presenters Tom and Maren Beard pose for a photo.