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At least 73 records · Page 4Linked to original sources
USGS1953

Ground-water conditions in artesian aquifers in Brown County, Wisconsin

The principal water-bearing rocks underlying Brown County, Wis., are thick sandstone units of Cambrian and Ordovician age. Other aquifers include limestone and dolomite of Ordovician age, dolomite of Silurian age, and sands and gravel of Pleistocene and Recent age. Underlying the water-bearing formations are crystalline rocks of pre-Cambrian age which contain little or no water. Ground water is the source of all public and most private and industrial supplies in. the county. Several of the large industries use large quantities of surface water also. Most of the water is pumped from wells that penetrate the Cambrian sandstones where the water occurs under artesian conditions. From 1886, when the first deep well was drilled, to 1949, the pumpage in the county increased to an average of about 5 million gallons a day (mgd) in 1939 and to about 10 mgd in 1949. The piezometric level, which was about 100 feet above the land surface in 1886, was about 300 feet below the land surface in 1949. About 200 feet of this decline took place after 1938. The water-level-measurement program begun in 1946 shows that yearly fluctuations of water levels in observation wells range from less than 1 foot to about 90 feet, the fluctuations being larger at the center of the heavily pumped area. The highest water levels occur in the winter or spring and the lowest in the summer near the end of the season of maximum withdrawal. Coefficients of transmissibility and storage for the sandstones were obtained by making controlled pumping tests at Green Bay and De Pere. The coefficients were verified by comparing computed water-level declines and rates of withdrawal with actual ones. The computed values were within I0 percent of the actual values. Probable declines of water levels by 1960 were computed, using the same coefficients of transmissibility and storage, and assuming three different conditions of pumping. The additional decline in water level will be 15 to 150 feet in the center of the pumped area, depending upon the amount of increased pumping and its distribution relative to the present pumped area and to the recharge area. The water from the sandstones is a hard calcium magnesium bicarbonate water. Further work is needed to determine whether there is danger of contamination by salt water which occurs down the dip in the same formations. It is concluded that the rate of withdrawal from the area can be increased to 15 mgd by 1960 without dangerously lowering water levels, provided that new wells are properly spaced. In order to avoid expressive lowering of water levels, it is recommended that new wells be located west of Green Bay toward the recharge area. A detailed study has not been made of shallow aquifers in the county. Further work should be done to evaluate the possibilities of auxiliary supplies from the limestone of the Platteville formation or from the Niagara dolomite. Conservation should be practice.4 by all users of ground water to avoid waste resulting in lower water levels and higher pumping costs.

Wisconsin↗
USGS1977

Geology and ground water in Door County, Wisconsin, with emphasis on contamination potential in the Silurian dolomite

Door County, a recreational and fruit-growing area bordering Lake Michigan in northeastern Wisconsin, has had a long history of ground-water contamination from surface and near-surface sources. Contamination is most severe in late summer when fruit-canning operations and the influx of tourists create additional wastes. Silurian dolomite is the upper bedrock unit in the county and yields generally adequate supplies of very hard water with locally objectionable concentrations of iron and nitrate. Thin soil cover and well-fractured dolomitic bedrock give easy entry to ground-water contaminants throughout large parts of Door County. Many contaminants enter the dolomite by surface or near-surface seepage. There is little attenuation of contamination concentrations in the well-jointed dolomite, and contaminants may travel long distances underground in a relatively short time. The major source of ground-water contamination is bacteria, from individual waste-disposal systems, agricultural, industrial, and municipal wastes. Areas of the county underlain by contaminated zones include only a small percentage of the total ground-water system and are separated by large volumes of ground water free of contamination. (Woodard-USGS)

Open-File Report↗
USGS1962

Geology and ground-water resources of Fond du Lac County, Wisconsin

The principal water-bearing rocks underlying Fond du Lac County, Wis., are sandstones of Cambrian and Ordovician age and dolomite of Silurian age. Other aquifers include dolomite of Ordovician age and sand. and gravel of Quaternary age. Crystalline rocks of Precambrian age, which underlie all the water-bearing formations, form a practically impermeable basement complex and yield little or no water to wells. Ground water is the source of all public and most private and industrial water supplies in the county. The municipalities and industries obtain water chiefly from wells that penetrate the sandstones of Cambrian and Ordorician age. The Platteville formation and Galena dolomite of Ordovician age and the Niagara dolomite of Silurian age supply water to most domestic and stock wells and to a few industrial wells. Several buried valleys in the bedrock surface contain water-bearing deposits of sand and gravel. The source of the ground water in Fond du Lac County is local precipitation. Recharge to the water-bearing beds occurs in most of the county but is greatest where the bedrock formations are near the surface. Ground water is discharged by seeps and springs, by evaporation and transpiration, and by wells. Ground-water levels in wells fluctuate in response to recharge and to natural discharge and pumping. In areas not affected by pumping, water levels generally decline through the summer months because of natural discharge and lack of recharge, recover slightly in the fall after the first killing frost, decline during the winter, and recover in the spring when recharge is greatest. In areas of heavy pumping, the water levels are lowest in late summer and highest in late winter. Water levels in wells in the Fond du Lac area were about 5 to 50 feet above the land surface in 1885, but they had declined to as low as 185 feet below the land surface by 1957. Coefficients of transmissibility and storage of the sandstones of Cambrian and Ordovician age were determined by making controlled aquifer tests at Fond du Lac. The coefficients were verified by comparing computed water-level declines with actual declines. The computed values were within about 30 percent of the actual values, a reasonable agreement for coefficients of this type. Probable declines of water levels by 1966 were computed, using the same coefficients of transmissibility and storage. If the distribution of wells and the rate of pumping remain the same in 1957-66 as they were in 1956, the water levels will decline about 5 feet more by 1966. If, however, the distribution of pumped wells remains the same but the pumping by the city of Fond du Lac increases at a uniform rate from the 3 mgd (million gallons per day) pumped in 1956 to 5 mgd in 1966, the water levels in 1966 will be at least 60 feet below those of 1956. Dispersal of wells to the northwest toward the recharge area would reduce the water-level declines. The results of pumping tests, of test holes tapping the Niagara dolomite indicate that wells producing at least 200 gpm (gallons per minute) could be developed east of the Niagara escarpment. The ground water in Fond do Lac County is, in general, a hard calcium and magnesium bicarbonate water, which contains excessive iron in some areas.

Wisconsin↗
USGS1965

Geology and ground-water resources of Dane County, Wisconsin

The purpose of the ground-water investigation of Dane County, Wis., was to determine the occurrence, movement, quantity, quality, and availability of ground water in the unconsolidated deposits and the underlying bedrock. The relationships between ground water and surface water were studied in general in Dane County and in detail in the Madison metropolitan area. An analysis was made of the hydrologic system of the Yahara River valley and of the effects of ground-water pumpage on that system.

Wisconsin↗
USGS1975

A digital-computer model for estimating hydrologic changes in the aquifer system in Dane County, Wisconsin

The extensive use of ground water for water supply within Dane County has resulted in the need for an appraisal of the area's ground-water resources. Water-resources planners and other water-oriented groups have expressed concern over ground-water level declines and reductions in streamflow that are occurring as a result of heavy pumping. Digital-computer modeling techniques were used to estimate hydrologic changes in the aquifer system that would be caused by continued development. The system was modeled as a two-aquifer system consisting of a confined sandstone aquifer overlain by a leaky unconfined aquifer and underlain by impermeable bedrock. The physical properties of the aquifer system needed for the model were approximated using aquifer-test data and well-log data and by matching observed hydrologic changes in the system with corresponding changes computed by the model. Computed hydrologic changes do not represent a serious depletion of the available ground-water supply for the foreseeable future. Maximum added regional declines in ground-water levels (drawdowns) from 1970 to 1990 were computed to be approximately 10 feet (3 metres) in the unconfined aquifer and approximately 40 feet (12 metres) in the confined aquifer. It is computed that for the same period the average annual streamflow from the upper Yahara River basin would be reduced by approximately 29 cubic feet per second (0.82 cubic metre per second). These changes are computed based on estimated development trends for the confined sandstone aquifer.

Wisconsin↗
USGS1980

Ground-water resources and geology of Washington and Ozaukee Counties, Wisconsin

Population growth is placing increased demands on water supplies in Washington and Ozaukee Counties. Water from three principal aquifers supplies most municipal, industrial, irrigation, residential, and farm water needs in these counties. These are the sand-and-gravel, Niagara, and sandstone aquifers. As much as 15 gallons per minute can be obtained from wells almost everywhere in these counties. Yields of 500 to 1,000 gallons per minute are available from the sand-and-gravel aquifer in parts of Washington County. The Niagara aquifer underlies most of the area and can yield as much as 500 gallons per minute in most of Ozaukee and eastern Washington Counties. It yields less than 100 gallons per minute in some areas, notably eastern Mequon in Ozaukee County and parts of western Washington County. The sandstone aquifer underlies the entire area and generally can yield more than 1,000 gallons per minute to wells. However, yields of less than 500 gallons per minute are common in southwestern Washington County, where the aquifer is thinnest.

Wisconsin↗
USGS1976

Ground-water resources and geology of St. Croix County, Wisconsin

The increasing need for good-quality ground water in St. Croix County, caused by a steadily increasing population, can be met from the sand-and-gravel and sandstone aquifers. As much as 15 gallons per minute (0.95 litres per second) can be obtained from wells almost everywhere in the county. Yields of more than 1,000 gallons per minute (63 litres per second) are available from glacial deposits and alluvium where there is sufficient thickness of saturated sand and gravel. The sandstone aquifer underlies the entire county and is more than 1,000 feet (300 metres) thick in the southwest near River Falls. In St. Croix County the sandstone aquifer is all bedrock younger than Precambrian age and includes, in ascending order, from oldest to youngest, sandstones of Cambrian age (in ascending order, the Mount Simon, Eau Claire, Galesville, and Franconia Sandstones, and the Trempealeau Formation); and the Prairie du Chien Group, St. Peter Sandstone, and Galena-Platteville unit (Platteville and Decorah Formations and Galena Dolomite, undifferentiated), all of Ordovician age. This aquifer is capable of yielding more than 1,000 gallons per minute (63 litres per second) to wells in much of the county and is the principal source of municipal water. The chemical quality of water from the two aquifers is similar. The water from both aquifers is hard to very hard, having a median hardness between 180 and 190 milligrams per litre. Iron and manganese are locally present in botherSome amounts (combined total exceeding 0.3 milligrams per litre). Nitrate is a minor problem in both aquifers, with median concentrations more than 10 milligrams per litre, possibly indicating some contamination of ground water by organic matter. About 3.83 million gallons per day (0.168 cubic metres per second) of ground water was pumped in the county in 1974, of which 94 percent was from the sandstone aquifer. About 44 percent of the total water pumped was for industrial and commercial use, 42 percent for residential

Wisconsin↗
USGS1976

Low-flow study of the Pike River Basin, Racine and Kenosha counties, Wisconsin

The low-flow characteristics of the Pike River basin, Racine and Kenosha Counties were studied to determine the feasibility of Public Law 566 watershed-protection practices. Two seepage runs, one in October 1973, and the other in September 1974, showed that most of the low flow is combined treated-sewage and industrial cooling-water discharge. This effluent was 4.66 cubic feet per second (1.3 cubic metres per second) on September 19, 1974, and discharged into the headwaters of the Pike River; near the mouth the discharge was essentially the same. During drought this effluent could be lost gradually by evapotranspiration and by seepage to the ground-water reservoir. The Q7,2 discharge estimate near the mouth is 0.0 cubic foot per second. Water temperatures October 25-26, 1973, ranged from 9.5 to 16 degrees Celsius, whereas those for. September 19-20, 1974, ranged from 10 to 22 degrees Celsius. Dissolved oxygen October 25-26, 1973, ranged from 4 to 13.5 milligrams per litre; for September 19-20, 1974, the range was from 6.0 to 12.5 milligrams per litre. Specific conductance October 25-26, 1973, ranged from 480 to 1,350 micromhos; for September 19-20, 1974, the range was from 380 to 1,400 micromhos.

Wisconsin↗
USGS1954

Ground-water conditions in southwestern Langlade County, Wisconsin

Glacial outwash sand and gravel deposits are the principal aquifer in southwestern Langlade County, Wis. The underlying bedrock of pre-Cambrian age contains little or no water. The source of ground water is local precipitation. Information was collected on more than 300 wells in the area. Movement of ground water is generally southward and locally toward streams. Discharge is by streams and subsurface flow. Fluctuations of water levels in wells show a close correlation with seasonal precipitation and with average precipitation over a period of years. Pumping tests made at the city of Antigo's well field gave a coefficient of transmissibility of 62,000 gpd per ft and a coefficient of storage of 0.15 for the outwash deposits. It is estimated that recharge to a 90-squaremile area of the Antigo flats averages about 30,000 acre-feet per year. Of the 1,100 acrefeet pumped from wells in 1948, 69 percent was for municipal supply, 26 percent for rural supply, and 5 percent for irrigation. Use of water for irrigation has caused no measurable decline of water levels in the area as a whole.

Wisconsin↗
USGS1965

Geology and ground-water resources of Waushara County, Wisconsin

Abundant ground water for irrigation is available in the outwash deposits in western Waushara County, and many more large-capacity wells can be developed in these deposits without seriously lowering the water level. Pumping for irrigation temporarily lowers water levels in the vicinity of the wells but has not lowered regional water levels. Pumpage has probably intercepted and utilized some of the recharge that would have been rapidly discharged from the aquifer. Ground water is continuously being discharged to streams and to the atmosphere by evapotranspiration, but intermittent recharge from precipitation replaces the discharged water. Recharge and discharge are in approximate balance, maintaining about the same amount of ground water in storage. Further recharge to the aquifer is rapidly discharged to streams. The sandstones, till, and glaciolacustrine deposits in Waushara County generally yield small to moderate amounts of water to wells but do not produce enough water for irrigation ; recent alluvium may yield large quantities of water to wells. In general, the ground water is of good quality, except for hardness and local high-iron concentrations.

Wisconsin↗
USGS1983

Geologic and aeromagnetic maps and mineral resource potential survey of the Blackjack Springs Wilderness, Vilas County, Wisconsin

The mineral resource potential of the Blackjack Springs Wilderness in the Nicolet National Forest, Vilas County, Wisc., was evaluated in 1982. No bedrock exposures are known in or near the wilderness. Geophysical data and regional geologic relations suggest that the area consists mostly of recrystallized and deformed mafic volcanic rocks and associated mafic intrusives of Early Proterozoic age. The only identified mineral resources in the Blackjack Springs Wilderness are sand and gravel, but these commodities are abundant regionally. While the occurrence of stratabound massive-sulfide (cooper-zinc-lead) and (or) magmatic sulfide (copper and (or) nickel)-type deposits are possible in the wilderness, their occurrence is not probable.

Wisconsin↗
USGS1955

Airborne and ground reconnaissance of part of the syenite complex near Wausau, Marathon county, Wisconsin

Airborne and ground reconnaissance for radioactive minerals in part of the syenite complex near Wausau, Marathon county, Wis., found 12 radioactive mineral localities. The rocks in the area are of Precambrian age and consist of syenite and nepheline syenite, which have intruded older granite, greenstone, quartzite, and argillite. There are very few outcrops, and much of the bedrock is deeply weathered and covered by residual soil. Thorium-bearing zircon pegatite float was found within the area of syenite and nepheline syenite at four localities. Reddish-brown euhedral to subeuhedral crystals of well-zoned zircon (variety cyrtolite) comprise more than 40 percent of some of the specimens. The radioactive mineral at four localities outside the area of syneites was identified as thorogummite, which occurred in nodular masses in residual soil. Alinement of the thorogummite float and associated radioactivity suggests that the thorogummite has resulted from weathering of narrow veins or pegmatites containing thorium-bearing minerals. Unidentified thorium-bearing minerals were found at three localities, and a specimen of allanite weighing about 2 pounds was found at one locality. Shallow trenches at two of the largest radioactivity anomalies showed that the radioactive material extended down into weathered bedrock. The occurrences might warrant additional physical exploration should there be sufficient demand for thorium. Further reconnaissance in the area would probably result in the discovery of additional occurrences.

Wisconsin↗
USGS1975

Ground-water resources and geology of Waukesha County, Wisconsin

Good-quality water is available from the sand-and-gravel, Niagara, and sandstone aquifers in Waukesha County, Wis. As much as 15 gallons per minute (0.95 litres per second) can be obtained from wells almost everywhere in the county. Several hundred gallons per minute are available from aquifers in the glacial drift that fill bedrock valleys to thicknesses of 300 feet (91 metres) or more. Estimated well yields from much of the surficial outwash in western Waukesha County exceed 500 gallons per minute (31 litres per second). Estimated well yields from most of the Niagara aquifer, a dolomite as much as 325 feet (99 metres) thick in the eastern two-thirds of the county, exceed 50 gallons per minute (3.2 litres per second). The sandstone aquifer underlies the entire county and ranges in thickness from about 400 feet (120 metres) in the northwest corner to about 2,400 feet (730 metres) in the southeast corner. This aquifer yields more than 1,000 gallons per minute (63 litres per second) to wells over most of the county and is the principal source for municipal and subdivision water. Ground water in Waukesha County is of good quality and is suitable for most uses. Most of the water is a calcium magnesium bicarbonate type, is very hard [more than 180 mg/l (milligrams per litre) hardness], and requires softening for some uses. The ground water locally contains iron and manganese concentrations that exceed the limits (0.3 and 0.05 mg/l, respectively) recommended by the U.S. Public Health Service (1962, p. 7). Water high in sulfate and dissolved solids (saline water) is present locally in the Niagara and sandstone aquifers. Water from one well contained excessive nitrate (more than 45 mg/l). With one exception, wells sampled at irregular intervals indicated no significant changes in their chemical characteristics with time. About 24.3 million gallons per day (1.06 cubic metres per second) of ground water was pumped in the county in 1970. Sixty-two percent was withdrawn from the sandstone aquifer. More than one-half of the latter amount was for domestic use, and more than one-third was for industrial and commercial uses.

Wisconsin↗
USGS2003

Simulation of ground-water flow and rainfall runoff with emphasis on the effects of land cover, Whittlesey Creek, Bayfield County, Wisconsin, 1999-2001

The effects of land cover on flooding and base-flow characteristics of Whittlesey Creek, Bayfield County, Wis., were examined in a study that involved ground-water-flow and rainfall-runoff modeling. Field data were collected during 1999-2001 for synoptic base flow, streambed head and temperature, precipitation, continuous streamflow and stream stage, and other physical characteristics. Well logs provided data for potentiometric-surface altitudes and stratigraphic descriptions. Geologic, soil, hydrography, altitude, and historical land-cover data were compiled into a geographic information system and used in two ground-water-flow models (GFLOW and MODFLOW) and a rainfall-runoff model (SWAT). A deep ground-water system intersects Whittlesey Creek near the confluence with the North Fork, producing a steady base flow of 17?18 cubic feet per second. Upstream from the confluence, the creek has little or no base flow; flow is from surface runoff and a small amount of perched ground water. Most of the base flow to Whittlesey Creek originates as recharge through the permeable sands in the center of the Bayfield Peninsula to the northwest of the surface-water-contributing basin. Based on simulations, model-wide changes in recharge caused a proportional change in simulated base flow for Whittlesey Creek. Changing the simulated amount of recharge by 25 to 50 percent in only the ground-water-contributing area results in relatively small changes in base flow to Whittlesey Creek (about 2?11 percent). Simulated changes in land cover within the Whittlesey Creek surface-water-contributing basin would have minimal effects on base flow and average annual runoff, but flood peaks (based on daily mean flows on peak-flow days) could be affected. Based on the simulations, changing the basin land cover to a reforested condition results in a reduction in flood peaks of about 12 to 14 percent for up to a 100-yr flood. Changing the basin land cover to 25 percent urban land or returning basin land cover to the intensive row-crop agriculture of the 1920s results in flood peaks increasing by as much as 18 percent. The SWAT model is limited to a daily time step, which is adequate for describing the surface-water/ground-water interaction and percentage changes. It may not, however, be adequate in describing peak flow because the instantaneous peak flow in Whittlesey Creek during a flood can be more than twice the magnitude of the daily mean flow during that same flood. In addition, the storage and infiltration capacities of wetlands in the basin are not fully understood and need further study.

Wisconsin↗
USGS1976

Regional flood limits of lower Yahara River, Lake Waubesa and south, in Dane County, Wisconsin

The purpose of this report is to provide information on the extent , depth, and frequency of flooding of the lower Yahara River in Dane County, Wis. The report contains discharge-frequency data for flood peaks, flood–frequency profiles, and the regional flood– (100-year flood) inundation limits for the lower Yahara River. The study reach is in southern Dane County extending from part of the shoreline of Lake Waubesa downstream through Lake Kegonsa to the Dane-Rock County line. Specifically the parts of the shoreline of Lake Waubesa included are those in and south of section 8, T. 6 N., R. 10 E. on the west shore and the south half of section 3, , T. 7 N., R. 10 E. on the east shore. (See figure 2.) The reach is 21 river miles (31 km) long. The Wisconsin Legislature has enacted flood–plain–Zoning legislation (1965) to encourage economic use of flood plains and to minimize flood losses. This act gave counties, cities, and villages the responsibility of enacting, administering, and enforcing reasonable and effective flood-plain regulations. This report is a sequel to earlier reports by Lawrence and Holmstrom (1971) and Holmstrom and Lawrence (1971). The earlier reports provided much of the same information, but the scale of the maps defining limits of flooding was much smaller. This report , using Orthophotographs at a scale of 1 in - 100 ft., provides greater detail. The report is based on conditions existing in 1971. All elevations are referenced to mean sea level, datum of 1929.

Wisconsin↗
USGS1972

Floods on Yahara River, Lake Kegonsa dam to county line, Dane County, Wisconsin

The State of Wisconsin, as a result of recent legislation, is establishing new, and upgrading old, minimum standards for flood-plain regulation. These standards require evaluations of the flood potential of many streams in Wisconsin. This report provides an evaluation of flood potential for the Yahara River in the 13-mile low-water channel reach from the dam at the outlet of Lake Kegonsa downstream to the county line. Prepared by the U.S. Geological Survey in cooperation with the Dane County Regional Planning Commission and the Wisconsin Department of Natural Resources, this flood-inundation study gives the computed water-surface elevations and defines the areal limits of inundation for the regional flood. The regional flood is defined by the Wisconsin Department of Natural Resources as a flood having an average frequency of occurrence of-once in 100 years and "which is representative of large floods known to have occurred generally in Wisconsin and reasonably characteristics of what can be expected to occur on a particular stream."

Wisconsin↗
USGS1989

Hydrogeology of Wood County, Wisconsin

The presence of low-permeability Precambrian rocks near land surface limits ground-water availability in the northern two-thirds of Wood County. Sand and gravel deposits provide large amounts of water (more than 500 gallons per minute) to some wells in the southeastern part of the county. Fine-grained unconsolidated deposits generally are less than 20 feet thick in the northern two-thirds of the county, but sand and gravel deposits 40- to 100-feet thick underlie the extreme southeastern part of the county. Horizontal hydraulic conductivity of the sand and gravel deposits ranges from about 155 to about 280 feet per day. The horizontal hydraulic conductivity of fine-grained unconsolidated deposits in the northern part of the county ranges from about 0.02 to 2 feet per day. Where unconsolidated deposits do not yield dependable water supplies, wells are finished in Precambrian rocks. Fractures occurring at shallow depths are the primary source of water for wells finished in Precambrian rocks. Because the number of fractures tends to decrease with depth, the horizontal hydraulic conductivity of these rocks generally decreases from about 11 feet per day in wells less than 50-feet deep to about 0.02 foot per day in wells greater than 160 feet deep. Estimates of ground-water recharge to sand and gravel deposits in the southeastern part of the county range from about 7 to 12 inches per year. Recharge estimates for the central and northern parts of the county range from about 1 to 4 inches per year. The total dissolved-solids concentration in ground water in Wood County is relatively low. Concentrations in water samples from 124 wells ranged from 21 to 578 milligrams per liter, with a median concentration of about 190 milligrams per liter. Major dissolved constituents are calcium, magnesium, and bicarbonate; sodium, potassium, chloride, and sulfate are present in low concentrations. The most common water-quality problem in Wood County is elevated iron concentrations. Iron concentrations greater than 300 micrograms per liter were found in 54 of 124 samples, and 15 samples contained iron concentrations greater than 5,000 micrograms per liter. Nitrate as nitrogen concentrations exceeded Wisconsin's drinking-water standard (10 milligrams per liter) in water from just 4 of 124 wells. The pesticide aldicarb was detected in 7 of 36 samples, and various volatile organic compounds were detected in 24 of 102 ground-water samples collected by the Wisconsin Department of Natural Resources since 1980. Wells in which these chemicals were detected are near irrigated agricultural fields and in commercially developed areas where buried gasoline-storage tanks and chemical spills are more likely to occur. A reconnaissance approach combining electromagnetic surveys and sampling for water-quality indicators was used to assess effects of leachate on ground water near seven landfills. Results of the electromagnetic surveys were used to site water-quality observation wells. Total dissolved-solids concentrations and concentrations of volatile organic compounds, chloride, sulfate, iron, chemical oxygen demand, and organic carbon are some of the chemical constituents analyzed in samples collected from these wells. The average rate of ground·water pumpage in Wood County in 1985 was 9.7 million gallons per day. Of this rate, about 6 million gallons per day is pumped from municipal-supply wells in seven communities.An additional 1.08 million gallons per day is pumped for agricultural irrigation.

Wisconsin↗
USGS2002

Simulation of Fish, Mud, and Crystal Lakes and the shallow ground-water system, Dane County, Wisconsin

A new MODFLOW lake package (LAK3) that simulates ground-water/lake interaction was used in simulation of Fish, Mud and Crystal Lakes?three shallow seepage lakes located in northwestern Dane County, Wis. The simulations were done to help determine the cause of increasing lake stages and provide a tool to estimate the effect of pumping water from Fish lake on future lake stages. The ground-water-flow model was developed using a telescopic-mesh refinement of the Dane and southwestern Columbia Counties regional model previously developed by the U.S. Geological Survey and the Wisconsin Geological and Natural History Survey. The parameter estimation model, UCODE, was coupled to the steadystate ground-water model to automate and optimize the calibration procedure. The steady-state model was calibrated to measured ground-water levels, Spring Creek streamflow measured at Lodi, and Fish and Crystal Lake stages. The results of the steady-state model were used as initial conditions in a transient simulation beginning in 1966 and ending in 1998. Recharge based on annual baseflow in Black Earth Creek, runoff based on measured coefficients, and precipitation and evaporation from the lake surfaces, were varied during the transient simulation. Measured Fish Lake stage was matched to simulated stage to calibrate the transient model. Model results suggest that the increase in regional ground-water recharge resulted in increased ground-water flow to the lake, which in turn resulted in increased lake stages. Simulation results of withdrawal of water from Fish Lake at 500 gallons per minute, assuming 1990?98 climatic conditions, indicate that after 1 year of pumping the stage of Fish and Mud Lakes would be reduced more than 1 foot and the stage of Crystal Lake would be reduced by less than 0.2 foot. When pumping is stopped, the lake stages would recover to near pre-pumping levels within about 3 years. When pumping is extended to 5 years, Fish and Mud Lake stage would be reduced by a maximum of 3.8 feet and Crystal Lake stage is reduced a maximum of 0.8 feet. After 4 years of recovery, Fish and Mud Lake stages are within 0.9 foot of prepumping levels and Crystal Lake stage is within 0.7 foot.

Wisconsin↗