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Source-linked reports with geographic coverage including Wisconsin.

At least 703 records · Page 39Linked to original sources
USGS1988

Hydrology and water quality of Delavan Lake in southeastern Wisconsin

Delavan Lake is a eutrophic, recreational lake in a densely populated area of southeastern Wisconsin. Sewage effluent and septic tank drainage were diverted out of the drainage basin of the lake to improve its water quality in 1981. The worst known blue-green algal bloom occurred in the lake in the summer of 1983. A comprehensive hydrologic and water-quality investigation was started in October 1983 to determine why the water quality in the lake apparently had not improved after cessation of influxes of waste waters. This report describes the hydrology and water quality of Delavan Lake and its drainage basin during the 1984 and 1985 water years. All major external inputs and outputs of phosphorus and nitrogen to the lake were measured to assess the importance of each source. Internal loading of phosphorus was calculated as a residual of a mass-balance budget. The in-lake phosphorus mass during the 2-year study shows a gradual declining trend that suggests an improving lake condition but also could be due to a random phosphorus decline. Future monitoring will be needed to determine whether the decline in phosphorus has indeed occurred as a result of waste-water diversion. Continuous streamflow and water-quality monitoring in the subbasins of the Delavan Lake watershed showed a wide range of annual phosphorus and nitrogen yields during the study. Jackson Creek tributary, which predominantly drains the city of Elkhorn, had the highest average yields of phosphorus (838 pounds per square mile) and Kjeldahl nitrogen (3,600 pounds per square mile). These yields were almost three times those found in the Jackson Creek basin, which has the largest livestock population. The other major tributary, Delavan Lake tributary 2, had much lower average annual yields of phosphorus (53.1 pounds per square mile) and Kjeldahl nitrogen (550 pounds per square mile). The lower yields in this tributary result from significantly reduced runoff caused by storage and evapotranspiration in a large pond that is surrounded by a wetland in the stream's basin. External loading of phosphorus and nitrogen were sufficient to cause eutrophic conditions. Internal loading of phosphorus was more than two times the external phosphorus supply. Most of the internal loading occurred when the hypolimnion was anoxic during summer. Internal loading of phosphorus during the 1985 water year was significantly reduced from that of 1984 because of a shorter anoxic period.

Wisconsin↗
USGS1988

Water resources of the Apostle Islands National Lakeshore, northern Wisconsin

The Apostle Islands National Lakeshore consists of 21 islands, part of the Bayfield Peninsula, and the adjacent waters of Lake Superior. Selected water resources of the Apostle Islands National Lakeshore were assessed to aid the National Park Service in developing and managing the Lakeshore and to provide a data base against which future changes can be compared. This summary of water-resources data, collected by the U.S. Geological Survey during 1979-84, provides a qualitative description of selected hydrologic components of the Lakeshore. Streamflow in the Lakeshore area is characterized by typical seasonal fluctuations. Flow in Sand River at State Highway 13 ranged from 3.9 to 1,630 cubic feet per second. The recurrence interval of the maximum observed discharge was about 4 years. The minimum observed 7-day low flow was 3.86 cubic feet per second. The greatest concentrations of most chemical constituents in Bayfield Peninsula streams occurred during base flow. Annual sediment loads in Sand River at State Highway 13 ranged from 977 tons in 1980 water year to 24,600 tons in 1984 water year.The average annual sediment load transported by Bayfield Peninsula streams to the National Lakeshore area of Lake Superior is estimated to be 44,000 tons. Annual phosphorus loads ranged from 1,400 pounds in 1980 water year to 11,100 pounds in 1984 water year. The average annual phosphorus load transported by Bayfield Peninsula streams to the National Lakeshore area of Lake Superior is estimated to be 21,500 pounds. Few island streams flow perennially, but Oak Island streams generally yield more base-flow runoff than Stockton Island streams. The base flow of Oak Island streams is dominated by ground-water discharge, whereas Stockton Island stream base flow is sustained by seepage from wetlands and beaver ponds. There are two major lagoons in the Lakeshore, the Outer Island Lagoon's area is 53 acres and its maximum depth is 7 feet. Dominant inflow to the lagoon is from precipitation on its surface and seepage from an adjacent bog. Outflow during open-water periods is dominated by evaporation. Ground-water seepage from the lagoon toward Lake Superior occurs yearround. The lagoon's water is acidic and has low specific conductance and generally small concentrations of most chemical constituents. The Michigan Island Lagoon is about 4 acres in area and its maximum depth is 6.5 feet. The most significant sources of inflow appear to be precipitation and wave washover from Lake Superior. Water from four deep-water monitoring sites in Lake Superior revealed concentrations of total phosphorus, organic carbon, and recoverable mercury ranging from <0.01 to 0.02 milligrams per liter, 1.1 to 5.3 milligrams per liter and <0.1 to 0.1 micrograms per liter, respectively. Neither pesticide residues nor fecal coliform bacteria were detected in the water column. Total phosphorus concentrations in bottom sediment ranged from 50 to 470 milligrams per kilogram and were related directly to the percentage of fine-grained (< 0.0625 millimeters) sediment particles. Traces of only two pesticide residues- DDE and DDT were detected in sediment. The most abundant benthic macroinvertebrate was Pontoporeia affinis, which was found in densities of from 960 to 2,100 organisms per square meter. No adverse affects resulting from visitor use were detected in the shallow-water, heavy-use areas in Presque Isle Bay off Stockton Island or in the waters between Rocky and South Twin Islands. Phosphorus and organic-carbon concentrations were similar to those observed in the deep-water area; mercury was not detected in water from either area. Ground-water use in the National Lakeshore is primarily for consumption by Lakeshore visitors and employees. Of 14 wells constructed from 1979-84, 4 were finished in glacial sand and gravel, and 10 were finished in sandstone. Specific capacities ranged from 0.63 to 50 gallon per minute per foot. Average concentrations of dissolved solids are moderate and concentrations of heavy metals did not exceed Wisconsin's primary health standard.

Wisconsin↗
USGS1988

A survey of the prevalence of selected bacteria in wild birds

We determined the prevalence of six genera of bacteria from a sample of 387 cloacal swabs from 364 passerines and woodpeckers. The prevalence of bacteria were as follows: Escherichia coli (1%), Pseudomonas spp. (22%), Salmonella spp. (0%), Staphylococcus spp. (15%), Streptococcus spp. (18%), and Yersinia spp. (1%). The prevalence of Streptococcus spp. was higher in omnivorous species than in granivorous species (20% versus 8%). Individuals captured at feeders had a lower prevalence of both Streptococcus spp. (15% versus 33%) and Escherichia coli (0.5% versus 4%) than birds that did not have access to feeders. These differences are probably not due to the feeder per se, but instead to other site related differences. The prevalence of bacteria did not differ between male and female black-capped chickadees, Parus atricapillus . For 279 color marked black-capped chickadees, we calculated the cumulative mortality rate during 12 wk following swabbing. Although the cumulative mortality rates of infected birds were consistently higher than the rates of non-infected birds, none of these differences were significant. Infections may cause slight reductions in survival rates, but we were not able to confirm this with our data.

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USGS1987

Embryotoxicity, teratogenicity, and aryl hydrocarbon hydroxylase activity in Forster's terns on Green Bay, Lake Michigan

Known reproductive problems, including congenital malformations and poor hatching success, exist for the state endangered Forster's tern ( Sterna forsteri ) in Green Bay, Wisconsin. Twenty Forster's tern eggs were collected from separate nests at (i) a natural colony with documented reproductive problems, situated at Green Bay, Lake Michigan, and (ii) an inland colony at Lake Poygan (control) where reproduction was documented as normal. Eggs from the two locations were placed in the same laboratory incubator and candled throughout incubation. Hatching success of Green Bay eggs was 52% of that for controls. Several early embryonic deaths occurred, but most mortality occurred close to the time of hatching. Liver microsomal aryl hydrocarbon hydroxylase activity was elevated approximately threefold in Green Bay hatchlings compared to controls. Green Bay terns that hatched weighed less than controls, had an increased liver to body weight ratio, and had a shorter femur length. Two Green Bay embryos that failed to hatch had anomalies, one with a crossed beak and one with poor ossification of the foot. One Green Bay hatchling had an abnormally ossified ilium. These effects were observed in eggs where there were measureable levels of aryl hydrocarbon hydroxylase inducers including polychlorinated biphenyls and polychlorinated dibenzo- p -dioxins.

Wisconsin↗
USGS1987

Prediction of the effects of mine dewatering on four lakes near Crandon, Wisconsin, by use of a water-budget model

The effects of dewatering a proposed zinc and copper mine on water levels of four lakes near Crandon, Wisconsin, were predicted by use of a digital water-budget model of the lakes. The average lake-stage reduction predicted by the model for expected ground-water levels after mine dewatering ranged from 0.21 feet for Duck Lake to 6.9 feet for Little Sand Lake. These stage reductions assume that no water is pumped into the lakes and that no changes are made to the outlet structures. The predicted flow augmentation to the lakes to offset lowering of ground-water levels by mine dewatering range from 8 gallons per minute for Duck Lake to 580 gallons per minute for Little Sand Lake. Because of uncertainty in variables used in the model and in the data used to calibrate the model, the predictions of the model are subject to an undetermined degree of uncertainty.

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USGS1987

Water use in Wisconsin, 1985

An inventory of water use in Wisconsin is essential for appraising current and future water-resource needs of the State. The U.S. Geological Survey has collected and published national water-use data every 5 years since 1950. Sources of data in these reports have not always been well documented, and the methods for collecting and reporting the data were not the same for all States. Some planning and management needs of the State are not met by water-use information that is available only every fifth year. The U.S. Geological Survey entered into a cooperative program with the Wisconsin Department of Natural Resources (WDNR) in 1978. The purpose of the program was to collect and compile reliable annual water-use data and to develop computerized water-use data systems at the State and national levels. Data in standardized format for different categories of water use are available in the State Water Use Data System. The data base is updated annually or when more current water-use information is available. Information about amounts of water withdrawn, source of water, how the water was used, and how much water was returned is available to those involved in establishing water-resource policy and to those managing water resources. The data contained in this report are a summary of the 1985 data-collection effort.

Wisconsin↗
USGS1987

An evaluation of the bedrock aquifer system in northeastern Wisconsin

Ground water is a major source of water in northeastern Wisconsin. The lower Fox River valley, located between Lake Winnebago and Green Bay in northeastern Wisconsin, is the second largest population center in Wisconsin. By 1957, ground-water withdrawals had lowered the potentiometric surface of the aquifer system as much as 440 feet below prepumping levels. With the exception of the city of Green Bay, which converted from ground water to surface water (Lake Michigan) for their municipal water supply in 1957, ground-water withdrawals have continually increased. The report evaluates the bedrock aquifer system in northeastern Wisconsin and describes how the flow regimes in the system have been altered due to ground-water withdrawals. A three-dimensional finite-difference groundwater flow model was used to aid in evaluation of the regional flow system. In order to simplify the study of the aquifer system, the geologic units were grouped into eight geohydrologic units consisting of four aquifers and four confining beds. The aquifers are the more permeable sand and gravel layers in the surficial deposits (aquifer 4), Devonian dolomite-Silurian dolomite (aquifer 3), St. Peter Sandstone- Prairie du Chien Group-Jordan Sandstone Member of the Trempealeau Formation (aquifer 2), and the Galesville Sandstone-Eau Claire Sandstone-Mount Simon Sandstone (aquifer 1). The confining beds are the less permeable silts and clays in the surficial deposits (confining bed 4), Maquoketa Shale-Galena Dolomite-Decorah Shale-Platteville Formation (confining bed 3), St. Lawrence Member of the Trempealeau Formation-Franconia Sandstone (confining bed 2), and the Precambrian crystalline rock (confining bed 1). The following aquifer and confining-bed characteristics were determined to represent the aquifer system of northeastern Wisconsin and were used in the development of the model. Aquifer 4 acts as an upper boundary of the bedrock aquifer system. The hydraulic conductivity of aquifer 3 was 7.9 feet per day and the storage coefficient was estimated to be 0.01. Transmissivity input values to the model for aquifer 2 are based on hydraulic conductivities ranging from 3 to 8 feet per day. The storage coefficient for aquifer 2 was 0.0002. The transmissivity input values to the model for aquifer 1 are based on hydraulic conductivities ranging from 2.5 to 8 feet per day and the storage coefficient was 0.0002. Confining bed 4 acts as an upper confining unit for the underlying bedrock aquifers. A vertical hydraulic conductivity of 0.007 foot per day was assigned to represent confining bed 4. The vertical hydraulic conductivity of confining bed 3 was assigned values of 0.0001 to 0.000004 foot per day. A value of 0.00001 foot per day was used as the vertical hydraulic conductivity for confining bed 2. Confining bed 1 is a lower boundary of the system and was not modeled. Model simulations indicate that, by 1914, ground-water withdrawals from the aquifer system had already impacted the study area. Pumping in the Green Bay metropolitan area had lowered the potentiometric heads in aquifer 1 by 69 feet and in aquifer 2 by 55 feet. Model simulations indicate that, by 1981, ground-water withdrawals have caused a cone of depression centered in the city of De Pere area. The influence of the cone affects almost the entire study area and has significantly altered the horizontal and vertical flow regimes in the aquifer system. In 1981, computed drawdowns below the prepumping potentiometric surface of aquifer 1 range from 0 feet on the western side of the study area to 330 feet in the center of the cone of depression. In aquifer 2, the computed drawdown ranges from 0 feet on the western side of the study area to 253 feet in the center of the cone.

Wisconsin↗
USGS1987

Simulation of unsteady flow in the Milwaukee Harbor Estuary at Milwaukee, Wisconsin

This report describes the application and results of an unsteady-flow model for the Milwaukee Harbor Estuary. The model simulates unsteady and upstream flow occurring in the estuary as a result of Lake Michigan Seiche. The discharge computed by the model indicates that upstream flow occurs throughout the estuary during periods of lake seiche. Flow conditions are extremely unsteady and major flow reversals may occur within 1 hr. The simulated discharge indicates that both upstream and downstream flows four times greater than the average daily discharge can occur during the same day. An estimate of 5- or 15-minute average discharge was required during selected runoff events and at various locations in the estuary as part of the Milwaukee Harbor Estuary study. The model provides a method to estimate 5-minute average discharges at selected cross sections in the estuary. The U.S. Geological Survey 's Branch Network Model was used to simulate stage and discharge. A finite difference computation scheme is used to solve the one-dimensional flow equations. Model input requirements include channel geometry data, discharge at the upstream tributaries, and stage data at the estuary mouth. The model was used to simulate the flow during six selected time periods in 1982-84 using a 5- or 15-minute computation interval. (Author 's abstract)

Wisconsin↗
USGS1987

Estimated use of ground water for irrigation in Wisconsin, 1984

The flow from a sample of 143 irrigation wells from 6 irrigation areas in Wisconsin was measured using an external flowmeter during the 1983-84 irrigation seasons. The measured pumpages were correlated with reported pumpages. The equation that describes this correlation is Q(sub)m = 0.86 x Q(sub)r where Q(sub)m is the measured pumpage and Q(sub)r is the reported pumpage. This equation was used to adjust all reported irrigation pumpage, yielding a more accurate estimate of total irrigation water use. The maximum total irrigation pumpage for 1984 was estimated to be 31,700 million gallons by using the equation and accounting for both reported and unreported pumpage. From 1979 to 1984, irrigation pumpage increased a maximum of 25% and the maximum number of irrigation wells increased 32%. (Author 's abstract)

Wisconsin↗
USGS1987

Cost effectiveness of the U.S. Geological Survey's stream-gaging program in Wisconsin

This report presents the results of a three-step evaluation of the stream-gaging program in Wisconsin. First, data uses and funding sources were identified for the 89 continuous-record gaging stations operated during the 1984 water year. Next, alternative methods of streamflow estimation were examined for three stations. A flow-routing model was used for two of the stations and a statistical model was used for the third. The modeled discharges did not compare well enough with observed discharges to warrant elimination of any of the stations. Finally, an optimization model was used to assess the cost effectiveness of the stream-gaging process. The annual budget, in 1984 dollars, for operating the 89 continuous-record gaging stations and 65 additional stations is $557,3000. Based on a Kalman-filter analysis, the theoretical average standard error of instantaneous discharge associated with the current practice of visiting the stations is 13.8%. This overall level of accuracy could be maintained with a budget of $518,6000 if stream-gaging activities were redistributed in an optimal fashion among the gaging stations. For the current budget, the theoretical average standard error would be reduced to 10.1% if the network is operated in an optimal fashion. Furthermore, the average standard error would be reduced to 7.3% if all missing record is eliminated and the network is operated optimally. A minimum budget of $510,000 is required to operate the program; a budget less than this does not permit proper service and maintenance of the gaging stations. At this minimum budget, the theoretical average standard error of instantaneous discharge is 14.4%. The maximum budget analyzed was $650,000 and resulted in an average standard of error of instantaneous discharge of 7.2%.

Wisconsin↗
USGS1987

Analysis of water-level fluctuations in Wisconsin wells

More than 60 percent of the residents of Wisconsin use ground water as their primary water source. Water supplies presently are abundant, but ground-water levels continually fluctuate in response to natural factors and human-related stresses. A better understanding of the magnitude, duration, and frequency of past fluctuations, and the factors controlling these fluctuations may help anticipate future changes in ground-water levels. This report presents the results of statistical analyses of historical ground-water level fluctuations in Wisconsin. Short- and long-term fluctuations are discussed in terms of their relation to components of the hydrogeologic system. Water-level measurements from 124 wells with at least 20 years of record each were used in the study. The mean, highest and lowest monthly mean, median, and selected quantiles were obtained using the SAS Proc Univariate procedure. The frequency values from the Univariate table were used to construct stage-duration graphs. Pearson Type ill frequency analyses were used to obtain probabilities of exceedance of particular water levels. The data were divided into seasonal data sets for each well. The stage-duration and Pearson Type III analyses are based on past fluctuations but may be useful for estimating future water-level changes under similar conditions. Multiple-regression analyses were run on data from groups of wells representing different ground-water districts. The SAS Proc Stepwise method was used. The regression model used average annual amplitude as the dependent variable and mean water level, mean annual precipitation, standard deviation of the seasonal mean precipitation, aquifer type, and topographic setting as the independent variables.This procedure produced different regression equations for each hydrogeologic district. Regression analyses also were done on data from groups of wells representing different aquifers. These regression models used average annual amplitude as the dependent variable and mean water level, topographic setting, and standard deviation of seasonal mean precipitation as the independent variables. Because of the many factors influencing ground-water level fluctuations, it was difficult to obtain a regression model that accurately reproduced average annual amplitude. The results of the regression analyses are helpful in recognizing the important variables; however, the equations are not effective in predicting the amplitude of a particular well because local conditions were omitted in the regional analyses. Hydrographs of average annual water level and frequency distribution analyses of annual maximum and minimum water levels were inspected for possible long-term trends. Analysis of annual maximum and minimum water levels indicates several periods in the annual cyclic fluctuations-two periods of recession (winter and summer), and two periods of rising levels (spring and fall). Usually, water levels are lowest in late winter and highest in spring for every annual cycle. The summer-fall minimum and the fall maximum are less distinct and do not occur every year. A composite frequency analysis of extreme annual water levels on 71 of the wells shows that the lowest levels most frequently occur in December, February, or March. However, the record low usually occurs in August, September, or October during drought. Ground-water levels most often peak in May, April, or June. In the fan they may peak from September through December, depending upon complexities of meteorological, geomorphological, and geological factors. The long-term cyclicity of ground-water level fluctuations is shown on hydrographs of wells Sw-7, Ln-25a, Mt-7, Ju-8, and Ju-98. Seasonal variations that tend to obscure the long-term trends are eliminated by plotting the average annual water levels. The hydrographs are similar even though the wells are 80 to 100 miles apart and constructed in different geologic materials. The long-term trends and the duration of the cycles apparently depend little on the location and on the lithologic composition of the aquifers, but rather on precipitation. The hydrographs show several periods of welldefined peaks and lows. The ground-water levels reached peaks in 1946, 1952, 1960, 1966, 1973, 1979. The average interval between these peaks is 6.6 years. The low levels occurred in 1949, 1955-59, 1964, 1970, and 1977; average interval between the low levels is 7.0 years, which is similar to that for the high levels. Long-term trends are apparent on hydrographs of wells Br-46, Mr-2S, Pt-276, Ro-3, and Ve-8. The trend of average annual water levels has been generally increasing since the late 1950's and is in general agreement with the increasing trend of precipitation. Hydrographs of well Ve-8, which has the longest period of record in Wisconsin, indicate that the generally rising trend started even earlier at the end of an extensive drought period in the 1930's.

Wisconsin↗
USGS1987

Water resources of Langlade County, Wisconsin

Langlade County depends almost exclusively on ground water pumped from the glacial sand and gravel deposits for its water needs. Well yields of 10 to 20 gallons per minute can be obtained from these deposits throughout most of the county. Yields of 500 to 1,000 gallons per minute are obtained for irrigation of crops from glacial outwash deposits in some areas of the county and particularly in the extensive 125-square-mile outwash plain in south-central Langlade County. Very low yields of less than 5 gallons per minute are obtainable for private domestic use from Precambrian crystalline rocks in areas of the county where overlying glacial material is thin. Glacial deposits are more than 400 feet thick in glacial moraine areas of east-central Langlade County; saturated thicknesses exceed 250 feet in the north-central part of the county. Horizontal hydraulic conductivity values of glacial material range from less than 1 foot per day in fine-grained glacial tills in western parts of the county to approximately 145 feet per day in outwash deposits. The transmissivity of glacial deposits ranges from essentially zero in areas of unsaturated glacial material to more than 40,000 feet squared per day in the outwash plain of southcentral Langlade County. Most surface and ground water originates from precipitation falling within the county. Streams and ground water flow into the county only in areas along its northern edge. Ground water supplies about 70 percent of the annual streamflow. Ground-water composition in Langlade County is similar to most ground water in the State and is of suitable quality for most uses. It is a calcium magnesium bicarbonate type. Concentrations of total dissolved solids are relatively low and range from 71 to 369 milligrams per liter, with a median value of 144 milligrams per liter. Dissolved iron and manganese concentrations exceeded secondary (aesthetic) standards in about 30 percent of all ground-water analyses. Values for total hardness as calcium carbonate ranged from 48 to 280 milligrams per liter for all samples. Ground water classified as very hard was confined to the southern part of the county where glacial deposits are higher in carbonate mineral content. An average of about 4.7 million gallons of water was pumped daily in Langlade County in 1983. Irrigation and fish rearing are the major ground-water uses in the county. An average of about 4.2 million gallons per day was pumped for irrigation during the months of June, July, and August. Results of this study show that present irrigation pumpage rates have little effect on groundwater levels in the Antigo Flats area.

Wisconsin↗
USGS1986

Groundwater flow into Lake Michigan from Wisconsin

Detailed hydrogeological study has been done at six sites along the Lake Michigan shoreline in Wisconsin. At each site a flux of groundwater to the lake has been calculated for both natural conditions and the existing conditions created by pumping. The values from each site have then been extrapolated to the entire portion of the total shoreline having similar hydrogeology in order to calculate a total flow of groundwater to the lake. Sensitivity analysis with a digital model was used to define limits on the similarity of hydrogeologic conditions. The net flow calculated is 580–880 m 3 day −1 km −1 of shoreline, which falls within the previously published range of 110–8200 m 3 day −1 km −1 . Human activity may have reduced the natural flow as much as 15%. The estimated natural flow is between 7 and 11% of the surface water contribution to the lake from the study area.

Wisconsin↗
USGS1986

Hydrogeology and ground-water quality of Lannon-Sussex area, northeastern Waukesha County, Wisconsin

The Silurian dolomite aquifer in the Lannon-Sussex area of southeastern Wisconsin is overlain by glacial deposits, but is within 8 ft of the land surface over 15% of the study area. The proximity of the dolomite aquifer to the land surface makes it susceptible to contamination from man 's activities. Water from the aquifer was analyzed and several characteristics were monitored in a 30-sq-mi area of Waukesha County, including: water temperature, calcium, magnesium, potassium, strontium, alkalinity, chlorides, fluorides, sulfates, nitrites, nitrates, nitrogen, iron, manganese, hardness, and pH. The water is hard, commonly having a hardness of more than 350 mg/L as CaCO 3 , and high in iron, commonly containing more than 0.3 mg/L. However, nutrient concentrations are not high; nitrogen, greater than 8 mg/L; phosphorus, none detected; and potassium, greater than 4 mg/L. The chloride content of the water averages more than 50 mg/L indicating contamination probably from septic systems. The water quality varies over a time. High concentrations of chloride and, occasionally, of bacteria correlate with periods of groundwater recharge over a period of 17 months. Chloride concentrations were highest in water from wells where housing density is high. An attempt was made to relate water quality changes with depth to beds of cherty dolomite that are identified in geologic logs; it was postulated that these zones might be confining beds. Although the beds appear to extend over the area, no evidence was found that they are confining beds, other than reports of a few artesian wells. Water quality, indicated by chloride content, showed no significant relation to well bottom altitudes, casing bottom altitude, or well depth.

Wisconsin↗
USGS1986

Effects of urbanization on streamflow, sediment loads, and channel morphology in Pheasant Branch basin near Middleton, Wisconsin

A 5-year, data-collection and modeling study was conducted on Pheasant Branch basin in and near Middleton, Wisconsin. The objectives of the study were to: (1) describe the streamflow characteristics, sediment transport, and stream-channel morphology in the Pheasant Branch basin; and (2) relate the above factors to changes caused by urbanization and project the effect of urbanization on the hydrology and channel morphology of the study area. Streamflow data were collected at five sites for 4 years in the basin to defme present streamflow conditions. Suspended-sediment data also were collected at these sites. In addition, periodic surveys of monumented channel cross sections were made and compared with a survey from an earlier study to document changes in the channel over a period of 10 years. The suspended-sediment data show a decrease in suspended-sediment load through the fully urbanized reach of the stream in 3 of the 4 years studied. This corresponds with the slight net decrease in cross-section area in this reach for the same period. Possible explanations for the decrease in suspended-sediment loads through this reach include (1) sediment being trapped at the five drop structures and the Park Street erosion-control structure and (2) sediment being deposited in overbank areas throughout the reach. Farther downstream, the suspended-sediment load decreased through the Pheasant Branch marsh during a year of high flow but increased through the marsh in 2 of the 3 years for which complete data are available. The marsh is not acting as a net sediment trap in some years. A rainfall-runoff model was calibrated and verified for the basin upstream from U.S. Highway 12. This model was used to simulate 68 years of summer flood hydrographs for three conditions: Current land use, projected urban development, and complete urban development of all lands in the basin. Analysis of simulated flood flows indicates that projected urban development would double the mean annual flood peaks at U.S. Highway 12. Complete development of the basin would increase the mean annual flood peak by a factor of 2.4. From 1971 to 1977, the mean streambed elevation lowered by almost 2 feet, and the mean channel width increased by more than 35 percent in the reach downstream from the fully urbanized part of the basin. In other reaches, the mean streambed elevation lowered by more than a foot. Changes in channel cross sections after 1977 were smaller. Increases in flood flow would tend to enlarge the channel. An increase in the mean annual flood by a factor of 2. 0 to 2.4 will cause a 40 to 50 percent increase in channel width and a 30 to 40 percent increase in channel depth.

Wisconsin↗
USGS1986

Relationship of nonpoint-source discharges, streamflow, and water quality in the Galena River basin, Wisconsin

Four small tributaries of the Galena River Madden Branch tributary, Pats Creek, Apple River, and Madden Branch that drain nonpoint agricultural sources and that receive no significant point-source discharges were monitored from October 1980 through September 1982 to determine water quality. Streamflow in the tributaries during the 1981 water year was about 25 percent below normal and, during the 1982 water year, about 38 percent above normal. Precipitation in the basin was near the 30-year normal during the 2-year study period. The yields of suspended solids, volatile solids, total phosphorus, and ammonia plus organic nitrogen during the 1982 water year were at least twice the yields of the 1981 water year. The greatest suspended-solids yield was 740 tons per square mile from Madden Branch tributary. The greatest yields of volatile solids (70.8 tons per square mile), total phosphorus (2,289 pounds per square mile), and ammonia plus organic nitrogen (8,529 pounds per square mile), were from Madden Branch. The lowest annual yields of suspended solids, volatile solids, total phosphorus, and ammonia plus organic nitrogen for both years were from the Apple River. Concentrations of many constituents were very high during runoff periods. The highest concentration of ammonia nitrogen 12 mg/L (milligrams per liter) measured during the study period was in Pats Creek during spring runoff, February 21, 1982. The highest concentration of total phosphorus, 17 mg/L, was measured in Madden Branch tributary during a storm on July 10, 1982. The storm of July 10 exceeded a 100-year recurrence interval of a 1-hour storm intensity for the area. Dissolved-oxygen concentration sags were noted at three of the monitoring stations during surface runoff. Although not all observed sags caused instream dissolved oxygen to fall to critical levels, one such decline was associated with a fishkill at Pats Creek. In that instance, highly oxidizable material with a biochemical-oxygen demand of 27 milligrams per liter was sampled at peak discharge; 16 hours later, the dissolved oxygen had dropped to 1.2 milligrams per liter. Concentrations of many constituents exceeded State and Federal water-quality standards. Dissolved-oxygen concentrations were lower than the minimum State standard on numerous occasions at all sites except Madden Branch tributary. Most phosphorus concentrations during periods of surface runoff at all sites exceeded U.S. Environmental Protection Agency standards. Concentrations of ammonia nitrogen potentially exceeded the Wisconsin State standard only once at Pats Creek.

Wisconsin↗