June 5, 2009

This is not your grandmother's water dousing. UNL geologists are analyzing data collected by high-tech helicopter-mounted equipment to pinpoint locations where water is likely to be found.

The large object hanging beneath this helicopter is gathering data about Nebraska's aquifers. (Source: Lower Platte South Natural Resources District)

Resource districts and others will be able to use the analyses for exploration, development and protection of groundwater supplies, said Jesse Korus, groundwater resources coordinator for the Conservation Survey Division of UNL's School of Natural Resources.

The helicopter conducts electromagnetic surveys to collect data about Nebraska's aquifers, Korus said. Interpreting this data requires direct sampling of materials from test holes and a team of geologists.

Equipment towed about 100 feet below the helicopter in a long tube maps geologic structures beneath the earth. The helicopter company, Fugro Airborne Surveys, of Ontario, Canada, works with pilots who are specially trained for low-level flying.

The surveys "can tell you what types of soils and materials exist under the surface," Korus said. "The red is materials like sand and gravel, from which groundwater can be pumped in large quantities, if it's saturated with water. The blue are materials in which groundwater doesn't flow readily, like clay or silt."

Korus used visualization software to produce a three-dimensional image that combines survey data with test-hole data for an area near Firth. This image is a preliminary version of a much more comprehensive analysis that will include maps, cross sections and images.

The most recent helicopter flights gathered data over rural Hickman, Sprague and Hallam in Lancaster County and rural Wahoo, Weston, Ithaca and Swedeburg in Saunders County. These studies build upon earlier HEM surveys conducted in 2007 near Firth, Ashland and Oakland.

Collaborators include the U.S. Geological Survey, the Lower Platte North and Lower Platte South Natural Resources Districts, the School of Natural Resources and the Nebraska Environmental Trust

Kelly Helm Smith
School of Natural Resources