Groundwater in Bayfield County

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1 Groundwater in Bayfield County Presented to Bayfield County Large Scale Livestoc Study Committee April 23, 2015 Madeline Gotowitz Hydrogeologist

2 Groundwater in Bayfield County Groundwater basics Hydrogeology across Wisconsin Hydrogeology in Bayfield County Mapping groundwater features

3 Wisconsin s Water Cycle

4 Groundwater discharge to Honey Cree is baseflow

5 Hydrogeology: Groundwater flows through roc and sediment Water under the ground, within an aquifer; porous sand, gravel and roc holds water

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7 Groundwater in dolomite and Distribution limestone of carbonate is vulnerable roc to contamination. Legend Silurian Su dolomite Sinnipee Os dolomite Prairie Opc du Chien dolomite

8 Bedroc within 50 feet of surface

9 Distribution of carbonate roc within 50 feet of surface

10 Calumet and Brown Counties

11 Wisconsin s groundwater contamination issues are significant The left jar contains brown water contaminated by manure. Both samples are from the same well.

12 Karst features can be easy to see Sinnipee Dolomite: Dane and Iowa Counties

13 Hydrogeology in Bayfield County

14 Hydrogeologic cross section U.S. Geological Survey Scientific Investigations Report pdf

15 Glacial geologic formations sandy till Courtesy of USGS

16 Thicness of glacial deposits Courtesy of USGS

17 Glacial geology Clayton, L., Pleistocene Geology of the Superior Region, Wisconsin. Information Circular C46 Wisconsin Geological and Natural History Survey.

18 Bedroc Geology Chequamegon Sandstone Sims, P.K., Geologic map of Precambrian rocs, southern Lae Superior region, Wisconsin and northern Michigan. U.S. Geological Survey, IMAP 2185 Freda Sandstone volcanics

19 Orienta Sandstone Amnicon Falls State Par Photo: E. Stewart, WGNHS

20 Wisconsin Groundwater Susceptibility Map Depth to bedroc, bedroc type, depth to water table, surficial geology, soil type

21 Wisconsin Groundwater Susceptibility Map Depth to bedroc, bedroc type, depth to water table, surficial geology, soil type

22 Example groundwater study Town of Byron Fond du Lac County

23 Depth to bedroc Town of Byron - Example

24 Water table elevation Town of Byron - Example

25 Groundwater recharge Town of Byron - Example Estimate accounts for: - Historical climate data - Soil moisture capacity - Soil type - land-use type

26 Groundwater contaminant susceptibility Combination of factors - Depth to bedroc - Bedroc type - Depth to water table - Recharge rate Town of Byron - Example

27 Town of Byron - Example Hydrogeologic cross sections

28 Iowa County Groundwater: susceptibility versus contamination Susceptibility Least susceptible Moderately susceptible Highly susceptible Most susceptible Nitrate, mg/l 893 wells tested 14 % > 10 mg/l NO 3 46 % > 2 mg/l NO 3 Data from Central Wisconsin Groundwater Center and UW Extension.

29 Next steps: questions and discussion Collect, compile and analyze data: Depth to the water table Depth to bedroc Glacial deposits (sandy till versus clay till) Bedroc type (sandstone or basalt) Map of groundwater recharge rates Develop a groundwater susceptibility map Facilitate use of this information through educational and outreach efforts in Bayfield County Cost and schedule