The Wisconsin Depattment of Agriculture, Trade and Consumer Protection (DATCP), U.S. Geological Survey (USGS), Wisconsin Geological and Natural History Survey (WGNHS), and Wisconsin Department of Natural Resources (DNR) are collaborating on a project to utilize airbome electromagnetic (AEM) surveying to update depth to bedrock maps in northeastern Wisconsin.
The use of AEM for this type of evaluation is new, but has been used historically in the energy and mineral sector for rapid and large area coverage capabilities. This effort is in response to public groundwater quality concerns, limited data on depth to bedrock, and to better understand how activities on the surface impact water quality.
DATCP anticipates helicopters will start surveying for bedrock depth in early January and is dependent on weather conditions. Surveying is scheduled to happen in northeast Wisconsin counties including Calumet, Manitowoc, Fond du Lac, and Manitowoc.
The study involves the use of a helicopter towing a large hoop hanging from a cable and will be highly visible given the half-mile spacing of the flight lines and low-flying aircraft. WGNHS is also sampling a three-mile control line prior to the flight to evaluate a variety of depth to bedrock measurements that the AEM surveying will be calibrated against.
The goals for this study are to update depth to bedrock maps to reduce the need for private landowners to verify existing maps, and to produce a data set that will enhance the understanding of aquifer properties in order to improve groundwater quality.
Local governments—including the City of New Holstein—and law enforcement officials have been notified of this surveying because they are located in an area where the helicopter may be flying and may receive questions from residents in the area related to the following:
• This is a highly visible project (low-flying helicopter towing instrumentation) that will likely interest the general public and bring attention to water quality issues.
• The project is a result from state and federal partners collaborating to address a public concern. It uses the strength of local, state, and federal resources to address an issue that affects many citizens in the northeastem part of the state where Silurian dolomite (an area more vulnerable to groundwater contamination) has been identified in soils.
• Funding has been secured to conduct the targeted flight area, but this project will not cover the entire area of interest. The project team is looking into funding options, with the ability to add additional funding up until the actual flight time, as well as for potential additional phases of the project to survey a larger area.
To learn more about the project and to find contact information, visit https:/ /datcp. wi.gov /Pages/Programs Services/ AEMSurvey.aspx.