Media Advisory: USGS Announces Low-Level Flights to Image Geology and Aquifers in Southwest Michigan

LANSING, Mich. - As part of a U.S. Geological Survey water-monitoring project, low-level helicopter flights are planned over southwest Michigan to image geology and aquifers using airborne geophysical technology.

Survey work will begin during the week of April 13, 2026, and will last approximately four months, weather permitting. The survey area spans 16 counties including Ottawa, Kent, Ionia, Allegan, Barry, Eaton, Ingham, Van Buren, Kalamazoo, Calhoun, Jackson, Berrien, Cass, St. Joseph, Branch and Hillsdale counties.

The flights will be based out of multiple small airports across the survey area. This survey will support a broader cooperative study, named Hydrologic Enhancement for Michigan, in partnership with the Michigan Department of Environment, Great Lakes, and Energy, which aims to enhance monitoring of groundwater to inform resource management. The survey data will be used to create three-dimensional maps of what's underground, down to more than 1,000 feet below the surface. These maps will show where layers of rock are located underground and the aquifers that supply drinking water and support other uses. This information will help scientists better understand how groundwater moves and help water managers make informed decisions about Michigan's water resources.

"The 3D models and maps are important for improving our understanding of water resources, and this type of airborne survey allows us to cover large areas very effectively," said Burke Minsley, a USGS research geophysicist in charge of the airborne survey. "The result is a 3D map of the subsurface that communities and water managers can use for decades."

The survey will use a helicopter equipped with a towed "hoop" that is deployed about 100 feet beneath the helicopter when in flight. Instruments in the hoop will measure differences in Earth's electrical properties and magnetic field created by different rock types across the survey area. The USGS has contracted with NV5, which has subcontracted SkyTEM to collect the data.

The scientific instruments on the helicopter do not pose a risk to humans, animals, or plant life. No photography or video data will be collected. The data collected will be made freely available to the public on ScienceBase once complete. The aircraft will be flown by experienced pilots who are specially trained and approved for low-level flying. The company works with the FAA to ensure flights are safe and in accordance with U.S. law. The surveys will be conducted during daylight hours only.

The helicopter will fly along preplanned flight paths relatively low to the ground at about 200 feet above the surface. Surveys do not occur over densely populated areas and the helicopter will not directly overfly buildings at low altitude. Flights will follow southwest-northeast lines spaced about one mile apart, with denser data collected over the Dowagiac River watershed and around the Tribal lands of the Pokagon Band of Potawatomi and the Match-E-Be-Nash-She-Wish Band of Pottawatomi (Gun Lake Tribe). The river corridors of the Kalamazoo, Thornapple, St. Joseph, Paw Paw, and Rocky Rivers will also be flown to improve our understanding of connections to subsurface geology along these corridors.