Groundwater, Wetlands, and Geology:  The Invisible Links

For April 11, 2018

Hi WN@TL Fans,

Few places are geographically outlined and culturally defined by its freshwater as Wisconsin is by its Great Lakes, its boundary rivers, its inland lakes & streams.

Even the etymological source of Wisconsin is in its water: the word comes from a Miami Indian phrase meaning “a river running through a red place.”

Beyond the lakes, streams and flowages are also Wisconsin’s wetlands.  Beneath the bodies of surface waters lie our groundwaters harbored in layer upon layer of rock—and the layers of rock differ in mineral composition, pore size, fissures and depth.

And so, depending on the lay of the land and the layers of rock, from the surface the water percolates down through the ground, it bubbles up in springs, and it flows as it goes.

Today not all goes well with the flow. From depleting the Central Sands to fouling the karst aquifers of Kewaunee County to polluting the urban water tables of Milwaukee, the waters of Wisconsin are a flashpoint in the environmental policy of the Dairy State.

This weekend, in the arena of protecting waters from farm pollution, at least one expert described that policy as a failure.

This week (April 11) Ken Bradbury, Wisconsin state geologist and director of the Wisconsin Geological & Natural History Survey of UW-Extension Cooperative Extension, updates us on a fundamental saga of Wisconsin:  the interplay between our waters and the rocks that carry, speed or impede them.  His talk is entitled: “Groundwater, Wetlands, and Geology:  The Invisible Links.”

Here’s how Ken describes his talk:

Although most people understand that Wisconsin’s wetlands are usually related to groundwater systems, these connections are often difficult to see. Why do wetlands occur where they do? Where does their water come from? How are they connected to the groundwater systems around them? Are they at risk from nearby groundwater extraction or other land-use changes? Hydrogeology helps to answer these questions. Using examples from three decades of research in Wisconsin, Bradbury will illustrate the invisible links among wetlands, groundwater, and geology.

About the Speaker

Kenneth Bradbury became the Wisconsin Geological and Natural History Survey’s director in September 2015. Prior to this, he had been a research hydrogeologist with the survey since 1982. Bradbury’s research interests include virus transport in groundwater, groundwater flow in fractured media, aquitard hydrogeology, groundwater recharge processes, wellhead protection, regional groundwater simulation, and the hydrogeology of glacial deposits.


Next week in the run-up to Earth Day, more on water and my favorite jawless fish:  the sea lamprey, a gift of the Erie Canal—or was it the Welland Canal?  In any case, for the past 100 years the sea lamprey has dined on the lake trout of Lake Michigan and Lake Superior.

While the invasive lamprey has not been eradicated in the upper Great Lakes, it has been controlled in part by the use of lampricides to kill young lampreys in rivers. But what is the fate of the lampricides? Where do they move and dwell and how are they broken down?

Christy Remucal of Civil & Environmental Engineering will shed some light on the lampricides on April 18.

Hope to see you soon at Wednesday Nite @ The Lab!

Thanks again,

Tom Zinnen
UW-Madison and UW-Extension