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USGS2021

Summary of fish communities along Underwood Creek, Milwaukee, Wisconsin, 2004–2019

Beginning in 2010, sections of Underwood Creek in Milwaukee County, Wisconsin, have undergone reconstruction to allow for improved fish habitat and better management of storm flows. In addition, dam and drop structures were removed to help improve fish migration while reintroducing several native fish species. With the reconstruction of Underwood Creek underway, the Milwaukee Metropolitan Sewerage District sought to evaluate if these measures have resulted in improvements to the fish community in the upstream parts of the watershed. The U.S. Geological Survey began sampling fish communities in 2004 at the farthest downstream site on Underwood Creek (Reach A) which was reconstructed in 2017. Reach B, which is slightly upstream, had undergone reconstruction in 2010 and fish community sampling began in 2016. A third reach farther upstream near Elm Grove was schedule to begin reconstruction in 2019. To compare the fish before and after reconstruction at the Elm Grove Reach, a fish community survey was conducted in spring of 2019 at Elm Grove and Reach B. This document describes the fish community from this sampling in comparison to previous surveys. Before reconstruction, Elm Grove Reach contained fish species more indicative of a slower, stagnant, warmwater stream than the other two rehabilitated reaches. Although six of the eight species found in Elm Grove Reach have been found at the lower reaches, all but two of the species are considered tolerant. Reconstruction of Elm Grove Reach to a similar habitat as the lower reaches will likely support a more diverse fish community.

Wisconsin↗

USGS2018

Evaluation of the effects of changes in the timing of water-level drawdowns on the export of phosphorus from Little St. Germain Lake, Wisconsin

Little St. Germain Lake is a 978-acre, multibasin lake in Vilas County, Wisconsin. In the interest of improving its water quality, the Little St. Germain Lake Protection and Rehabilitation District initiated a cooperative study with the U.S. Geological Survey to describe the current phosphorus input into and export from Little St. Germain Lake and evaluate how water releases at different times of the year could affect the amount of phosphorus being released from the lake, potentially affecting water quality in the lake. Approximately 780 pounds per year of phosphorus are exported out of the lake, which is about 80 percent of that contributed to the lake by Muskellunge Creek. By focusing the release of water to times when phosphorus concentrations near the outlet of the lake are highest, export of phosphorus from the lake could increase by about 60 to 80 pounds annually. This is equivalent to reducing phosphorus contributions from Muskellunge Creek by about 7 to 9 percent. Increasing phosphorus export from the lake should improve the long-term water-quality of the lake, especially in the southern basins of the lake.

Wisconsin↗

USGS2021

Assessment of groundwater trends near Crex Meadows, Wisconsin

Crex Meadows Wildlife Area (Crex) is a 30,000-acre property in Burnett County, Wisconsin. Crex is managed by the Wisconsin Department of Natural Resources (WDNR) with the goal of providing public recreation opportunities while also protecting the quality of native ecological communities and species on the property. The WDNR’s management strategy includes controlling water levels at flowages in Crex using a system of dikes, water control structures, ditches, and a diversion pump. For the past several decades there has been concern among nearby landowners that the water manage-ment strategy at Crex may be contributing to groundwater flooding in adjacent, privately held properties. This issue has been particularly contentious during periods when regional groundwater elevations are already high. This study was conducted in response to those concerns. For the study, a network of 12 monitoring wells was installed in and to the west of Crex. Groundwater elevations were recorded in the wells before, during, and after water-level changes in the western Crex flowages to assess if groundwater elevations to the west of Crex are detectably affected by the flowage water levels. This study successfully collected groundwater elevations in 11 study wells during a 3-month period in 2019 when water elevations in the Dike 6 flowage and Erickson flowage were lowered and then raised. The data logger at a 12th location failed and no data were recorded. The groundwater elevation trends in these study wells were compared with groundwater elevation trends at a regional U.S. Geological Survey well to provide information for determining if changing the flowage elevations had a noticeable response in the study wells west of Crex Meadows. This analysis was done by (1) evaluating study well groundwater elevation trends compared to the regional well, (2) using a scatter plot of study well and regional well data during raising and lowering periods, (3) assessing horizontal hydraulic gradient data during the study period, and (4) assessing the cumulative departure from the mean groundwater elevation for each well. Overall, regional groundwater elevations had a down-ward trend before and during the flowage lowering period and then had an upward trend during the flowage raising period. This pattern was observed in the regional well and in all the study wells adjacent to and several miles from the flowages. The similarity in patterns indicates that precipitation and regional groundwater flow conditions were the dominant drivers of the system during the study period. The scatter plot and cumulative departure from the mean analysis showed that in addition to regional trends, wells 1, 6, and 7 were likely affected by the changes in the flowage water levels. Overall, at least on the timescale of this study, water management at Crex likely did not have detectable effects on wells outside the Crex property. Wells installed on the Crex property including the wells in the lakebeds of the flowages (wells 1 and 7) and possibly well 6 east of the flowages showed what seems to be minor affects due to water management at Crex.

Wisconsin↗

USGS1971

Hydrology of Pine Creek, Wisconsin

The purpose of this study was to determine the hydrologic characteristics of Pine Creek, Price County, Wisconsin, in order to evaluate a proposed reservoir on Pine Creek. The streamflow characteristics estimated are the mean flows, low flows, and flood peaks. The study was done by the U.S. Geological Survey in cooperation with the Wisconsin Department of Natural Resources.

Wisconsin↗

USGS2003

A positive relationship between groundwater velocity and submersed macrophyte biomass in Sparkling Lake, Wisconsin

We measured groundwater velocity and submersed macrophyte biomass at 52 shal- low (0.4-6.6 m) sites in mesotrophic Sparkling Lake, Vilas County, Wisconsin, during May-Au- gust 1985. Seventeen percent of variation in macrophyte biomass was explained by a signifi- cant (P < 0.005) relation with depth [log(biomass + 1) = 0.49 depth - 0.08 (depth)2 + 0.121. Some of the remaining variation in macrophyte bio- mass was explained by a significant rank corre- lation of biomass-on-depth residuals with groundwater velocity (rs = 0.46, P < 0.0 1). These results suggest that water movement through the sediment-water interface may be a determinant of macrophyte abundance and distribution.

Wisconsin↗

USGS2012

Estimation of natural historical flows for the Manitowish River near Manitowish Waters, Wisconsin

The Wisconsin Department of Natural Resources is charged with oversight of dam operations throughout Wisconsin and is considering modifications to the operating orders for the Rest Lake Dam in Vilas County, Wisconsin. State law requires that the operation orders be tied to natural low flows at the dam. Because the presence of the dam confounds measurement of natural flows, the U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, installed streamflow-gaging stations and developed two statistical methods to improve estimates of natural flows at the Rest Lake Dam. Two independent methods were used to estimate daily natural flow for the Manitowish River approximately 1 mile downstream of the Rest Lake Dam. The first method was an adjusted drainage-area ratio method, which used a regression analysis that related measured water yield (flow divided by watershed area) from short-term (2009–11) gaging stations upstream of the Manitowish Chain of Lakes to the water yield from two nearby long-term gaging stations in order to extend the flow record (1991–2011). In this approach, the computed flows into the Chain of Lakes at the upstream gaging stations were multiplied by a coefficient to account for the monthly hydrologic contributions (precipitation, evaporation, groundwater, and runoff) associated with the additional watershed area between the upstream gaging stations and the dam at the outlet of the Chain of Lakes (Rest Lake Dam). The second method used to estimate daily natural flow at the Rest Lake Dam was a water-budget approach, which used lake stage and dam outflow data provided by the dam operator. A water-budget model was constructed and then calibrated with an automated parameter-estimation program by matching simulated flow-duration statistics with measured flow-duration statistics at the upstream gaging stations. After calibration of the water-budget model, the model was used to compute natural flow at the dam from 1973 to 2011. Daily natural flows at the dam, as computed by the adjusted drainage-area ratio method and the water-budget method, were used to compute monthly flow-duration values for the period of historical data available for each method. Monthly flow-durations provide a means for evaluating the frequency and range in flows that have been observed for each month over the course of many years. Both methods described the pattern and timing of measured high-flow and low-flow events at the upstream gaging stations. The adjusted drainage-area ratio method generally had smaller residual errors across the full range of observed flows and had smaller monthly biases than the water-budget method. Although it is not possible to evaluate which method may be more "correct" for estimating monthly natural flows at the dam, comparisons between the results of each method indicate that the adjusted drainage-area ratio method may be susceptible to biases at high flows due to isolated storms outside of the Manitowish River watershed. Conversely, it appears that the water-budget method may be susceptible to biases at low flows because of its sensitivity to the accuracy of reported lake stage and outflows, as well as effects of upstream diversions that could not be fully compensated for with this method. Results from both methods are useful for understanding the natural flow patterns at the dam. Flows for both methods have similar patterns, with high median flows in spring and low median flows in late summer. Similarly, the range from monthly high-flow durations to low-flow durations increases during spring, decreases during summer, and increases again during fall. These seasonal patterns illustrate a challenge with interpreting a single value of natural low flow. That is, a natural low flow computed for September is not representative of a natural low flow in April. Moreover, alteration of natural flows caused by storing water in the Chain of Lakes during spring and releasing it in fall causes a change in the timing of high and low flows compared with natural conditions. That is, the lowest reported dam outflows occurred in spring and highest reported outflows occurred in fall, which is opposite the natural patterns.

Wisconsin↗

USGS2005

Lithology, hydraulic properties, and water quality of the Sandstone Aquifer in the northwestern part of the Bad River Indian Reservation, Wisconsin, 1998-1999

The Precambrian sandstone aquifer in the northwestern part of the Bad River Band of Lake Superior Tribe of Chippewa Indians Reservation, Ashland County, Wisconsin, provides much of the drinking water to area residents. A study was undertaken in cooperation with the Bad River Tribe to provide specific information about the lithology, hydraulic properties, and water quality of the sandstone aquifer. During 1998 and 1999, the U.S. Geological Survey installed three monitoring wells, collected and analyzed lithologic and water samples, and conducted geophysical logging and aquifer tests to characterize the sandstone aquifer. The two monitoring wells in the southeastern part of the study area, the Diaperville Monitoring Well #1 (Diaperville MW #1) and the Tolman Monitoring Well #1 (Tolman MW #1) , are believed to have encountered older Middle Proterozoic Oronto Group sandstones. The sandstone encountered in the Ackley Monitoring Well #1 (Ackley MW #1) is believed to be Chequamegon Sandstone of the Late Proterozoic Bayfield Group. This interpretation is based on previous studies, as well as thin- section analysis of sandstone core recovered from the Ackley Monitoring Well #1. Results of aquifer tests conducted in the Diaperville Monitoring Well #1 and the Tolman Monitoring Well #1 provide ranges for hydraulic param - eter values in the sandstone aquifer: transmissivity ranges from 83 to 509 square feet per day; hydraulic conductivity ranges from 1.6 to 4.5 feet per day; storativity ranges from 0.00019 to 0.00046; and specific capacity ranges from 0.22 to 0.67 gallons per minute per foot. Though high- and low-angle fractures are present in Ackley Monitoring Well #1 core, the hydraulic properties of the bedrock appear to be due largely to the matrix porosity measured in thin section (16–21 percent) and permeability of the sandstone. The aquifer test for the Diaperville Monitoring Well #1 resulted in observed drawdown in nearby glacial wells, evidence of a hydraulic connection between the sandstone aquifer and the glacial deposits. Major ion analyses indicate that the water sampled from the sandstone aquifer at the Ackley site is of the calcium-magnesium-sodium- bicarbonate type. Based on a single sampling set, volatile organic constituents were not detected in water samples from the Diaperville Monitoring Well #1 or the Ackley Monitoring Well #1.

Wisconsin↗

USGS2008

Trichinella murrelli in scavenging mammals from south-central Wisconsin, USA

Tissues and serum from 59 raccoons (Procyon lotor), 42 coyotes (Canis latrans), and seven Striped Skunks (Mephitis mephitis) collected in Dane and Iowa Counties, Wisconsin, USA, between October 2005 and March 2006 were microscopically and serologically examined for the presence of Trichinella spp. Encapsulated larvae were found on compression slides prepared from tongue tissues from a few animals. Complete tissue digestion of tongues revealed that 19% of the raccoons, 26% of the coyotes, and none of the seven skunks tested were infected with Trichinella spp. Cats were subsequently experimentally infected by feeding them the raccoon tissues containing muscle larvae, and muscle larvae isolated from the collected tongues were experimentally transmitted to mice. Multiplex polymerase chain reaction analysis of the isolated muscle larvae demonstrated two distinct bands migrating at 127 base pairs (bp) and 316 bp in all samples, which together are diagnostic for Trichinella murrelli; the isolates were assigned Istituto Superiore di Sanita (ISS) codes ISS1656 through ISS1667, and ISS1708 through ISS1710 by the International Trichinella Reference Centre. These findings extend the geographic range of T. murrelli into Wisconsin, USA. ?? Wildlife Disease Association 2008.

Journal of Wildlife Diseases↗

USGS2005

Water quality, hydrology, and phosphorus loading to Little St. Germain Lake, Wisconsin, with special emphasis on the effects of winter aeration and ground-water inputs

Little St. Germain Lake is a 978-acre, multibasin lake in Vilas County, Wisconsin. In the interest of protecting and improving the water quality of the lake, the Little St. Germain Lake District initiated several cooperative studies with the U.S. Geological Survey between 1991 and 2004 to (1) document the water quality and the extent of winter anoxia in the lake, (2) evaluate the success of aerators at eliminating winter anoxia, (3) develop water and nutrient budgets for the lake, and (4) assess how the water quality of the lake should respond to changes in phosphorus loading. This report presents the results of these cooperative studies with special emphasis on the water quality in the lake since 2000, including the effects of winter aeration and the importance of ground-water contributions of phosphorus to the productivity of the lake. Measurements collected during these studies indicate that the water quality in Little St. Germain Lake was consistently different among basins. The West Bay consistently had the best water quality, the South Bay had intermediate water quality, and the East and Upper East Bays consistently had the worst water quality. The water quality in each of the basins was relatively stable from 1991 to 2000; however, since 2001, the West Bay has changed from oligotrophic to mesotrophic, the South Bay has changed from mesotrophic to eutrophic, and the East and Upper East Bays have changed from eutrophic to eutrophic/hypereutrophic. Winter anoxia frequently occurred throughout most of the lake, except in the West Bay and just below the ice in the East Bay. To eliminate winter anoxia, coarse-bubble line aerators were installed and operated in the Upper East, East, and South Bays. The aerators in the Upper East and South Bays were very successful at eliminating winter anoxia; however, the aerator in the East Bay had little impact on the dissolved oxygen concentrations throughout its basin. Detailed water and phosphorus budgets computed for the lake indicated that inflow from Muskellunge Creek was the major source of phosphorus to the lake and that ground water was the secondary source. Results from a detailed ground-water-flow model indicated that ground water flows into the lake from all sides, except the south sides of the West and Second South Bays. Most of the phosphorus appears to come from natural sources, such as ground water and surface water flowing through relatively undeveloped areas surrounding Little St. Germain Lake and Muskellunge Lake. Several empirical water-quality models were used to simulate how the East and Upper East Bays of the lake should respond to reductions in phosphorus loading from Muskellunge Creek. Simulation results indicated that reductions in tributary loading could improve the water quality of the East and Upper East Bays. Improving the water quality of these bays would also improve the water quality of the South and Second South Bays because of the flow of water through the lake. However, even with phosphorus loading from Muskellunge Creek completely eliminated, most of the lake would remain borderline mesotrophic/eutrophic because of the contributions of phosphorus from ground water.

Wisconsin↗

USGS2022

Simulation of regional groundwater flow and groundwater/lake interactions in the Central Sands, Wisconsin

A multiscale, multiprocess modeling approach was applied to the Wisconsin Central Sands region in central Wisconsin to quantify the connections between the groundwater system, land use, and lake levels in three seepage lakes in Waushara County, Wisconsin: Long and Plainfield (The Plainfield Tunnel Channel Lakes), and Pleasant Lakes. A regional groundwater-flow model, the Newton Raphson formulation of the U.S. Geological Survey modular finite-difference flow model groundwater-modeling package (MODFLOW-NWT), centered on the lakes, was used to extend regional surface-water boundaries to provide boundary conditions for two focused inset models, in the hydrologic simulation modeling package (MODFLOW 6), at higher resolution around the lakes. Land use and groundwater use were simulated at a regional scale using the Soil Water Balance model, which provided recharge and water-use boundary conditions for the MODFLOW models. Agricultural irrigation is the primary groundwater use in the area. Land and groundwater-use scenarios representing no irrigation, current (2018) irrigation, and potential future irrigation were simulated with the groundwater-flow model and the lake levels over a 38-year representative climate period.

Wisconsin↗

USGS1949

Index of surface-water records, part 12, Pacific slope basins in Washington and upper Columbia River basin, to September 30, 1948

The groundwater resources of Wood County, Wisconsin, are described. Groundwater is pumped only from wells drilled in Precambrian rock in the northern two-thirds of the county. The generally low permeability of this rock limits the availability of groundwater in this area. Saturated deposits of sand and gravel yield more than 500 gal/min to wells in the southern part of the county. Background groundwater quality and indicators of groundwater-quality problems, such as elevated concentrations of nitrate, chloride, hardness, and iron, are compared by aquifer for the entire county. An elevated concentration of iron is the major water quality problem in the county. Results of water quality analysis from observation wells drilled next to abandoned landfills throughout the county indicate that groundwater in the immediate vicinity of these landfills has been affected by leachate. The report includes maps of the thickness and saturated thickness of unconsolidated deposits, a water-table map, and tables of aquifer-production and well-production data from about 1,500 drillers ' well-construction reports. (USGS)

Circular↗

USGS2003

Lichens promote flowering Opuntia fragilis in west-central Wisconsin

Clumps of the cactus Opuntia fragilis growing in association with mats of the lichens Cladina mitis , Cladina rangiferina and a spikemoss, Selaginella rupestris , were discovered in an agricultural field in Pepin County, Wisconsin, that had been abandoned for over 50 y. The association appeared to be beneficial to the cactus, which flowered almost exclusively in the presence of lichens. Of 294 cactus clumps examined in 2001, 127 grew in the presence of lichen mats and, of these, 24 flowered, producing 91 flowers, while none of the cacti growing in the absence of lichens flowered. In 2002, 19 out of 265 cactus clumps flowered, all but one in the presence of lichens. All sizes of cacti in the presence of lichens flowered and the probability of flowering increased with cactus size. In addition, the cacti that flowered had cladodes that were on average 19% heavier than those of cacti that did not flower. The presence of lichens lowered summer soil temperatures 2–4 C compared to soil temperatures in the absence of lichens. Cooler soil temperatures conserve soil moisture better, which may enhance flowering in these cacti.

Wisconsin↗

USGS2014

Simulation of groundwater flow and interaction of groundwater and surface water on the Lac du Flambeau Reservation, Wisconsin

The Lac du Flambeau Band of Lake Superior Chippewa and Indian Health Service are interested in improving the understanding of groundwater flow and groundwater/surface-water interaction on the Lac du Flambeau Reservation (Reservation) in southwest Vilas County and southeast Iron County, Wisconsin, with particular interest in an understanding of the potential for contamination of groundwater supply wells and the fate of wastewater that is infiltrated from treatment lagoons on the Reservation. This report describes the construction, calibration, and application of a regional groundwater flow model used to simulate the shallow groundwater flow system of the Reservation and water-quality results for groundwater and surface-water samples collected near a system of waste-water-treatment lagoons. Groundwater flows through a permeable glacial aquifer that ranges in thickness from 60 to more than 200 feet (ft). Seepage and drainage lakes are common in the area and influence groundwater flow patterns on the Reservation. A two-dimensional, steady-state analytic element groundwater flow model was constructed using the program GFLOW. The model was calibrated by matching target water levels and stream base flows through the use of the parameter-estimation program, PEST. Simulated results illustrate that groundwater flow within most of the Reservation is toward the Bear River and the chain of lakes that feed the Bear River. Results of analyses of groundwater and surface-water samples collected downgradient from the wastewater infiltration lagoons show elevated levels of ammonia and dissolved phosphorus. In addition, wastewater indicator chemicals detected in three downgradient wells and a small downgradient stream indicate that infiltrated wastewater is moving southwest of the lagoons toward Moss Lake. Potential effects of extended wet and dry periods (within historical ranges) were evaluated by adjusting precipitation and groundwater recharge in the model and comparing the resulting simulated lake stage and water budgets to stages and water budgets from the calibrated model. Simulated lake water budgets and water level changes illustrate the importance of understanding the position of a lake within the hydrologic system (headwater or downstream), the type of lake (surface-water drainage or seepage lake), and the role of groundwater in dampening the effects of large-scale changes in weather patterns on lake levels. Areas contributing recharge to drinking-water supply wells on the Reservation were delineated using forward particle tracking from the water table to the well. Monte Carlo uncertainty analyses were used to produce maps showing the probability of groundwater capture for areas around each well nest. At the Main Pumphouse site near the Village of Lac du Flambeau, most of the area contributing recharge to the wells occurs downgradient from a large wetland between the wells and the wastewater infiltration lagoons. Nonetheless, a small potential for the wells to capture infiltrated wastewater is apparent when considering uncertainty in the model parameter values. At the West Pumphouse wells south of Flambeau Lake, most of the area contributing recharge is between the wells and Tippecanoe Lake. The extent of infiltrated wastewater from two infiltration lagoons was tracked using the groundwater flow model and Monte Carlo uncertainty analyses. Wastewater infiltrated from the lagoons flows predominantly south toward Moss Lake as it integrates with the regional groundwater flow system. The wastewater-plume-extent simulations support the area-contributing-recharge simulations, indicating that there is a possibility, albeit at low probability, that some wastewater could be captured by water-supply wells. Comparison of simulated water-table contours indicate that the lagoons may mound the water table approximately 4 ft, with diminishing levels of mounding outward from the lagoons. Four scenarios, representing potential alternatives for wastewater management, were simulated (at current discharge rates) to evaluate the potential extent of wastewater in the aquifer and discharge to surface-water bodies associated with each management scenario. Wastewater simulated to infiltrate through a hypothetical diffuser below a wetland south of the current lagoons appears to discharge to the overlying wetland and would likely discharge to Moss Lake as overland flow. Wastewater simulated to discharge to a small lake (Mindy Lake) between Moss and Fence Lakes appears to spread radically over a large area between the lakes. Wastewater simulated to discharge to lagoons south and northeast of the current lagoons also appears to spread radially, but the areas of the aquifer with the highest probability of encountering waste-water contamination would likely be between the lagoons and the nearest lake, where the wastewater would eventually discharge. Probability results for the wastewater-plume-extent scenarios are sensitive to the number of mathematical water particles used to represent infiltrating wastewater and the level of detail in the synthetic grid used for the probability analysis. Thus, probability results from wastewater-plume-extent simulations are qualitative only; however, it is expected that illustrations of relatively high or low probability will be useful as a general guide for decision making. Management problems requiring quantitative estimates of probability are best re-cast into problems evaluating the area that contributes recharge to the location of interest, which is not dependent upon the number of simulated particles or the resolution of a synthetic grid.

Wisconsin↗

USGS2011

Grassland bird use of oak barrens and dry prairies in Wisconsin

Grassland bird populations have declined more than any other group of birds in North America and are of conservation concern to state and federal agencies. We determined relative abundances of grassland birds in oak barrens and dry sand prairies—native habitat types rare in the state of Wisconsin. We also investigated the association of relative abundance, patch size, and patch vegetation. Our study was conducted May–July 2000–2002 on Fort McCoy Military Installation in Monroe County, Wisconsin. Fourteen grassland bird species were found in native habitat patches. Vesper sparrow ( Pooecetes gramineus ), grasshopper sparrow ( Ammodramus savannarum ), and field sparrow ( Spizella pusilla ) were the most abundant grassland bird species; all are species of management concern in Wisconsin. Of the most abundant species, only grasshopper sparrow relative abundance increased as patch size increased; vesper sparrow and field sparrow relative abundances decreased as patch size increased. Though found at lower relative abundances, horned larks ( Erephila alpestris ), savannah sparrows ( Passerculus sandwichensis ), and upland sandpipers ( Bartramia longicauda ) were found at higher relative abundances as patch size increased. Patch vegetation was important for some species. Vesper sparrows were found at higher abundances in patches with shorter, less dense vegetation and higher woody cover, eastern meadowlark ( Sturnella magna ) relative abundances were higher in patches with higher proportions of grass, and dickcissel ( Spiza americana ) relative abundances were higher in patches with taller, denser vegetation and lower proportions of litter. Native habitats are important for grassland bird species of management concern and large patches are particularly important for some of them.

Wisconsin↗

USGS2019

Groundwater flow model for Western Chippewa County–Including analysis of water resources related to industrial sand mining and irrigated agriculture

A groundwater flow model for western Chippewa County, Wisconsin, was developed by the Wisconsin Geological and Natural History Survey (WGNHS) and the U.S. Geological Survey (USGS) using the computer program MODFLOW. The model is the result of a five-year groundwater study commissioned by Chippewa County in 2012 to evaluate the effects of industrial sand mining and irrigated agriculture on the county’s water resources. The study incorporates existing data and newly acquired data from fieldwork conducted within the study area. The groundwater model may be useful for future investigations, such as evaluation of proposed high-capacity well sites, development of municipal wellhead protection plans, and studies that seek to further quantify surface water-groundwater relationships. The model conceptualizes the hydrostratigraphy of western Chippewa County as six stacked layers. Each layer is distinct, beginning with unlithified glacial material at the surface, and alternating between sandstones (that act as aquifers) and shale units (that serve as aquitards). The model is bounded below by Precambrian crystalline bedrock and its perimeter was derived from a regional-scale groundwater flow model. The MODFLOW model represented average conditions during 2011–2013 with “steady-state” assumptions, meaning that simulated water levels do not fluctuate seasonally or from year to year. Steady-state models simplify natural variability, making results of scenario simulations easier to interpret and compare while also maximizing effects of stressors because the simulated stress is always applied (not halted after a few months or years). Model calibration used the parameter estimation code (PEST), and calibration targets included heads (groundwater levels) and streamflows. Calibration focused on 2011–2013 because a large amount of head and streamflow data were available for that period. The MODFLOW model explicitly simulates all sources and sinks of water, including groundwater/surface-water interaction with streamflow routing. Model input included estimates of aquifer hydraulic conductivity and a spatial groundwater recharge distribution developed using a GIS-based soil-water-balance (SWB) model applied to the model area. Groundwater withdrawals were simulated for 269 high-capacity wells across the entire model domain, which includes western Chippewa County and adjacent portions of Dunn, Barron, and Rusk Counties. Collectively, these wells withdrew about 1.14 million gallons per year between 2011 and 2013. Once the model was calibrated, it was applied to two distinct scenarios of increased groundwater withdrawals: one evaluating hydrologic effects of more intensive industrial sand mining and the second evaluating the hydrologic effects of more intensive agricultural irrigation practices. Each scenario was developed with input from Chippewa County and a stakeholder group established expressly for this study. The scenarios were designed to represent reasonable future buildout conditions for both mining and irrigated agriculture. The mining scenario underscores the potential hydrologic effects related to changing land-use practices (i.e., hilltops and farmland becoming sand mines), while the irrigated agriculture scenario illustrates the potential hydrologic effects of intensifying existing land-use practices (i.e., installing new wells to irrigate farm fields). While each scenario evaluated distinctly different conditions, modeling results demonstrated the potential of both scenarios to lower the water table and reduce baseflows in headwater streams within the modeled area. In the case of irrigated agriculture, hydrologic effects were associated directly with groundwater withdrawals. By assuming that irrigation did not decrease, this steady-state simulation represented a sustained future effect. By contrast, hydrologic effects of industrial sand mining were the result of both groundwater withdrawals at mines and land-use changes that effectively reduced recharge to groundwater over distinct phases of active mining. This scenario included a post-mining phase, during which groundwater withdrawals stopped and mined areas were reclaimed to undeveloped prairie grass cover. If reclamation to undeveloped prairie indeed occurs as simulated, long-term increases in the water table and stream baseflows are possible. In this sense, the scenario representing build out of irrigated agriculture led to long-term baseflow declines while the future buildout of industrial sand mining led to declines that dissipated following mine reclamation to undisturbed prairie. Future investigations in similar hydrogeologic settings may find the following insights gleaned from this study useful: ❚❚ The characterization of hydrogeologic properties, delineation of hydrogeologic units, and calibration of groundwater flow models benefited from incorporation of accurate well construction reports, high-quality borehole geophysical logs, and streamflow gaging data. ❚❚ Infiltration testing performed in active mining areas provided evidence that reducing the degree and extent of compaction and enhancing areas designed to retain and infiltrate stormwater runoff could potentially reduce runoff and increase groundwater recharge. ❚❚ Similarly, reclaiming mined areas to prairie grasses would be expected to reduce runoff and increase groundwater recharge by reducing compaction and improving soil structure and vegetation that can slow runoff and enhance infiltration.

Wisconsin↗

USGS2021

Appendix C: Central sands lakes study technical report: Modeling documentation

This report provides the necessary documentation of the numerical models developed for the Central Sands Lake study in central Wisconsin and will be included as a technical appendix in the report to the Wisconsin State Legislature by the Wisconsin Department of Natural Resources (WDNR) in response to 2017 Wisconsin Act 10. This legislation directed WDNR to determine whether existing and potential groundwater withdrawals are causing or are likely to cause significant reduction of mean seasonal water levels at Pleasant Lake, Long Lake, and Plainfield Lake (s. 281.34(7m)(2)(b), Wis. Stats.) in Waushara County, Wisconsin. To evaluate the potential hydrologic connection between groundwater withdrawals and the nearby study lakes, hydrologic models were created that focused on the lakes of interest and yet were large enough to cover a broad enough region to extend to the major hydrologic boundaries of the natural flow system. The areas near the lakes require finer-scale grid discretization (or spacing) to better represent the lakes and streams in the model, but also need to cover a large enough area to include the groundwater withdrawal locations that have the potential to cause reduction in water levels in the lakes. To accomplish these goals, three groundwater models were created: a regional model extending to major hydrologic boundaries; and two inset models, inheriting boundaries from the regional model but focused near the lakes. Each of the inset models, in turn, included a detailed area close to the lakes surrounded by an area at the same spatial scale as the regional model (Figure 1). To support WDNR in evaluating the connection between groundwater withdrawals and lake levels, a representative time period was required over which to compare land use with and without irrigated agriculture and for WDNR to evaluate potential lake stage and flux changes related to irrigated agriculture. WDNR chose the climate period of 1981-2018 to be representative of a typical period and provided two land use scenarios—one with no irrigated agriculture and one with assumed crop rotations similar to current conditions—to simulate with groundwater models to, then, compare lake responses with. As a result, simulations over this climate record are not intended to recreate the history of 1981-2018 because land use changed over that time. These runs are, instead, intended to provide a basis on which to compare land use with and without irrigation-related groundwater withdrawals based on the current arrangement of land use and a varied climatic record. Groundwater withdrawals focused on irrigated-agriculture-related water use because greater than 95% of groundwater withdrawal in the two inset models around the study lakes is for irrigated agriculture water use. The period of 2012-2018 was used for parameter estimation (synonymously referred to as “history matching”) for the groundwater models. This time period was chosen because it includes the most complete water use records to simulate groundwater withdrawals. History matching was performed using groundwater elevations, lake stages, and streamflow observations over the 2012-2018 time period and processed observations derived from those raw data. Climatic data were incorporated into the model using a soil-water balance approach. A soil water balance model was constructed at the scale of the regional groundwater model to both calculate recharge based on land use and climate, and in the long-term climate-period runs, to estimate water use required by irrigated agriculture to apply as well boundary conditions in the groundwater model in the absence of reported water use values over that period.

Wisconsin↗

USGS1996

Element concentrations on Hypogymnia physodes (L.) Nyl. after three years of transplanting along Lake Michigan

Improvements in air quality in air polluted areas are often followed by recolonization of habitats by sensitive lichens that had died out when air quality was worse. To test the hypothesis that air quality at Indiana Dunes National Lakeshore has improved such that lichens could recolonize the area, samples of a species that once grew in the park, Hypogymnia physodes , were transplanted from Door County, Wisconsin to the park and three other sites along the western shore of Lake Michigan, including one at the site of origin as a control. The lichens were sampled for 3 years and tissue concentrations of 20 chemical elements were measured. There were no significant differences between concentrations over the 3 year study duration at the control site in Door County, suggesting that transplanting itself had no impacts on tissue concentrations. All but two elements increased in concentration from north to south with the greatest increases occurring in the third year of the study. Lichens at Indiana Dunes at the end of the study had suffered severe mortality. Chromium increased the most from north to south but concentrations were not higher than maxima observed in other studies. Arsenic and sulfur, however, exceeded known toxic thresholds or maxima observed in other studies on this species. Four hypotheses are presented to explain the toxicity of elements to this species.

Indiana, Wisconsin↗

USGS2001

Organochlorine contaminants and biomarker response in double-crested cormorants nesting in Green Bay and Lake Michigan, Wisconsin, USA

Double-crested cormorant ( Phalacrocorax auritus ) eggs at pipping and sibling 10-day-old chicks were collected from two colonies in Green Bay, WI, one colony in Lake Michigan, WI, and reference colonies in South Dakota and Minnesota. Egg contents and chicks were analyzed for organochlorine contaminants including polychlorinated biphenyl (PCB) congeners. Livers of embryos and chicks were assayed for hepatic microsomal ethoxyresorufin- O -dealkylase (EROD) activity. Eggshell thickness and the physical dimensions of embryo brains were measured. Concentrations of organochlorines, including p,p′-DDE (p,p′-dichlorodiphenyldichloroethylene), PCBs, and PCB congeners were generally an order of magnitude higher in eggs and chicks from Wisconsin than from reference locations. Total PCBs averaged 10–13 μg/g wet weight in eggs from three Wisconsin colonies compared to 0.9 μg/g PCBs from reference locations. Double-crested cormorant chicks accumulated on average 33–66 μg PCBs/day and 7–12 μg p,p′-DDE/day in the Wisconsin colonies compared to 0 μg PCBs/day and 1 μg p,p′-DDE/day in the reference colonies. At pipping, EROD activity in the livers of cormorant embryos was significantly higher in the Wisconsin colonies and significantly correlated with PCBs and the toxic equivalents (TEQs) of aryl hydrocarbon-active PCB congeners relative to 2,3,7,8-tetrachlorodibenzo- p -dioxin. However, in 10-day-old chicks EROD activity was not consistently different among colonies and was not correlated with PCBs or TEQs. A significant negative relationship between embryo brain asymmetry and the size of the egg suggested that physical constraint might be an important factor influencing the response of this bioindicator. Thinner eggshells in two colonies located near Door County, Wisconsin, suggested that historic p,p′-DDE residues associated with orchards are still an important source of p,p′-DDE in the local environment.

Minnesota, South Dakota, Wisconsin↗