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Source-linked reports with geographic coverage including Michigan.

At least 271 records · Page 15Linked to original sources

Hydrogeology and ground-water quality, Chippewa Township, Isabella County, Michigan, 2002-05

The ground-water resource potential of Chippewa Township, Isabella County, Mich. was characterized on the basis of existing hydrogeologic data, water-level records, analyses of water samples, and interpretation of geophysical survey data. Eight ground-water samples were collected and analyzed for major ions, nutrients, and trace-metal composition. In addition, 10 direct current-resistivity soundings were collected throughout Chippewa and Coe Townships to identify potential freshwater in the aquifer system. The aquifer system includes complexly interbedded glaciofluvial, glaciolacustrine, and basal-lodgment tills, which overlie Jurassic or Pennsylvanian sedimentary rocks. In parts of the township, freshwater is present in all geologic units, but in most areas saline water is encountered near the base of Pleistocene glacial deposits and in the Jurassic or Pennsylvanian bedrock. A near-surface sheet of relatively dense basal-lodgment till likely prevents, or substantially retards, significant direct recharge of ground water to glacial and bedrock aquifers in Chippewa and adjacent townships. Glacial sands and gravels form the principal aquifer for domestic wells (97.5 percent of wells in the township). The single community water supply in the township has wells screened in glacial deposits near the base of the glacial drift. Increased withdrawals of ground water in response to increasing demand has led to a slight decline in water quality from this supply. This water-quality decline is related primarily to an increase of dissolved sulfate, which is probably a function of well depth and dissolution of gypsum, a common mineral constituent in the Jurassic “red beds” , which form the uppermost bedrock unit throughout most of the township. One explanation for the increase in sulfate is upconing of saline water from bedrock sources, which may contain saline water.

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Michigan basin regional ground water flow discharge to three Great Lakes

Ground water discharge to the Great Lakes around the Lower Peninsula of Michigan is primarily from recharge in riparian basins and proximal upland areas that are especially important to the northern half of the Lake Michigan shoreline. A steady-state finite-difference model was developed to simulate ground water flow in four regional aquifers in Michigan's Lower Peninsula: the Glaciofluvial, Saginaw, Parma-Bayport, and Marshall aquifers interlayered with the Till/"red beds," Saginaw, and Michigan confining units, respectively. The model domain was laterally bound by a continuous specified-head boundary, formed from lakes Michigan, Huron, St. Clair, and Erie, with the St. Clair and Detroit River connecting channels. The model was developed to quantify regional ground water flow in the aquifer systems using independently determined recharge estimates. According to the flow model, local stream stages and discharges account for 95% of the overall model water budget; only 5% enters the lakes directly from the ground water system. Direct ground water discharge to the Great Lakes' shorelines was calculated at 36 m3/sec, accounting for 5% of the overall model water budget. Lowland areas contribute far less ground water discharge to the Great Lakes than upland areas. The model indicates that Saginaw Bay receives only ∼1.13 m 3 /sec ground water; the southern half of the Lake Michigan shoreline receives only ∼2.83 m 3 /sec. In contrast, the northern half of the Lake Michigan shoreline receives more than 17 m 3 /sec from upland areas.

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Conservation genetics of the endangered Isle Royale gray wolf

The small group of wolves on Isle Royale has been studied for over three decades as a model of the relationship between large carnivores and their prey. During the last ten years the population declined from 50 individuals to as few as 12 individuals. The causes of this decline may be food shortages, disease, or reduced genetic variability. We address the issues of genetic variability and relationships of Isle Royale wolves using allozyme electrophoresis, mtDNA restriction-site analysis, and multilocus hypervariable minisatellite DNA analysis (genetic fingerprinting). Our results indicate that approximately 50% of the allozyme heterozygosity has been lost in the island population, a decline similar to that expected if no immigration had occurred from the mainland. The genetic fingerprinting data indicate that the seven sampled Isle Royale wolves are as similar as captive populations of siblings. Surprisingly, the Isle Royale wolves have an mDNA genotype that is very rare on the mainland, being found in only one of 144 mainland wolves ThFF suggests that the remaining Isle Royale wolves areprobably derived from a single female founder.

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Water use for irrigation in Michigan, 2001

Each year, water-use data for Michigan are compiled or estimated by the Michigan Department of Environmental Quality (MDEQ), working in cooperation with the U. S. Geological Survey (USGS). The resulting information provides a category-by-category profile of over 4,200 facilities throughout the State. The data are reported in the Michigan Water Use Reporting Program, which provides needed information for water-resources planning and enhances public understanding of the value of sustaining water resources within the Great Lakes Basin. The primary goal of the program is to inventory, analyze, and report baseline data for major water uses.

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PCB concentrations in Pere Marquette River and Muskegon River watersheds, 2002

Polychlorinated biphenyl compounds (PCBs) are a class of209 individual compounds (known as congeners) for which there are no known natural sources. PCBs are carcinogenic and bioaccumulative compounds. For over 40 years, PCBs were manufactured in the United States. The flame resistant property of PCBs made them ideal chemicals for use as flame-retardants, and as coolants and lubricants in transformers and other electrical equipment. PCBs were also used in heating coils, carbonless paper, degreasers, varnishes, lacquers, waterproofing material, and cereal boxes. In addition, they were frequently used in the manufacturing of plastics, adhesives, and paints. During the manufacturing period of PCBs, these chemicals entered the environment though atmospheric release during manufacturing and burning of PCB products, leaks and spills, and improper disposal. Although PCB manufacturing was banned over 20 years ago, PCBs still enter the environment from hazardous waste sites, improper disposals of PCB-containing products, weathering of asphalt and other substances containing PCBs, burning of PCB containing products, leakage from old equipment, leaching from landfills, and release from contaminated sediments. PCBs do not readily break down in the environment, thus remain there for long periods of time. A small amount may remain dissolved in water but most adhere to organic particles and bottom sediments. In sufficient concentrations, PCBs affect human, wildlife, and aquatic health. PCBs accumulate in fatty tissues of animals and fish and are passed on to those that eat them. PCBs are animal teratogens and potentially carcinogenic. They can cause death of animals, fish, and birds; death or low growth rate of plants; shortened lifespan; reproductive problems; and lower fertility. Women who are exposed to high levels of PCBs may have babies with slightly lower birth weights and transfer the PCBs through the breast milk, which may affect the immune system and motor development of the child. Rule 323.1057 (Toxic Substances) of the Part 4. Water Quality Standards gives procedure for calculating water-quality values to protect human, wildlife and aquatic life. For total PCB, the applicable Rule 57 water-quality value is the human cancer value (HCV=0.26 ng/L), In 2002, U. S. Geological Survey (USGS) and Michigan Department of Environmental Quality (MDEQ) cooperatively planned and executed a monitoring program for PCBs in water and sediment from the Pere Marquette River and Muskegon River watersheds. The Pere Marquette and Muskegon River are in the west central part of Michigan's Lower Peninsula (fig. 1). The Pere Marquette River watershed is about 750 square miles, and the Muskegon River is about 2700 square miles. Both rivers are popular recreational waters, and the Pere Marquette River is a Michigan designated Natural River (Part 305 of the Natural Rivers and Environmental Protection Act 451 of 1994).

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Ground-water/surface-water relations along Honey Creek, Washtenaw County, Michigan, 2003

The U.S. Geological Survey (USGS), in cooperation with the city of Ann Arbor, Mich., investigated the ground-water/ surface-water relations along the lower reaches of Honey Creek, Washtenaw County, Mich., and an unnamed tributary to Honey Creek (the discharge tributary) from June through October 2003. Streamflow in these reaches was artificially high during a naturally low-flow period due to an anthropogenic discharge. Ground-water/surface-water relations were examined by seepage runs (series of streamflow measurements for the computation of streams gains or losses) and measurements of the difference in head between the stream surface and shallow aquifer. Specific conductance and water-temperature measurements were used as ancillary data to help identify gaining and losing reaches. Three seepage runs and four runs in which hydraulic-head differences between the stream and shallow aquifer were measured (piezometer runs) were made during periods of base flow. Streamflow measurements were made at 18 sites for the seepage runs. Instream piezometers were installed at 16 sites and bank piezometers were installed at 2 sites. Two deeper instream piezometers were installed at site 13 on September 4, 2003 to collect additional data on the ground-water/surface-water relations at that site. The seepage runs indicate that the main stem of Honey Creek and the discharge tributary in the study area are overall gaining reaches. The seepage runs also indicate that smaller reaches of Honey Creek and the discharge tributary may be losing reaches and that this relation may change over time with changing hydraulic conditions. The piezometer-run measurements support the seepage-run results on the main stem, whereas piezometer-run measurements both support and conflict with seepage-run measurements on the discharge tributary. Seepage runs give an average for the reach, whereas piezometer head-difference measurements are for a specific area around the piezometer. Data that may appear to be conflicting actually may be showing that within a gaining reach there are localized areas that lose streamflow. The overall gain in streamflow along with specific measurements of head differences, specific conductance, and water temperature indicate that ground water is discharging to Honey Creek and the discharge tributary. Although reaches and areas that lose streamflow have been identified, data collected during this study cannot confirm or disprove that the loss is to the regional ground-water system.

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Water resources on and near the Nottawaseppi Huron band of Potawatomi indian tribal lands, Calhoun County, Michigan, 2000-03

The Nottawaseppi Huron Band of Potawatomi Indians in Calhoun County, Michigan is concerned about the water quality and quantity of streams in and around tribal lands and of shallow ground water. The tribe wanted to establish a database that included streamflow, stage, and water quality of local streams and quality of ground water from wells belonging to the tribe and its members. Concerned about the effects of long-term agricultural activity and increasing numbers of singlefamily dwellings being constructed within the watershed both on and off the reservation, the tribe wants to develop a water-resources management plan. U.S. Geological Survey (USGS) measured streamflow and installed staff gages tied into local datum on three tributaries of the St. Joseph River that cross tribal lands. Water-quality samples were collected from the sites under a variety of flow regimes from spring to fall during 2000-03. Stage-streamflow rating curves were constructed for Pine Creek and Athens & Indian Creek Drain after a number of discharge measurements were made and a thorough basin analysis was completed. Daily streamflow for Pine Creek near Athens was estimated for the period from May 2000 through September 2003. USGS collected 12 water samples at Pine Creek near Athens, Athens & Indian Creek Drain, and an unnamed tributary to Pine Creek during October 2000 through September 2003. Physical properties were measured, and the streams were sampled for major ions, nutrients, trace elements, caffeine, and herbicides/pesticides and their breakdown products (degradates). The tribe also measured physical properties weekly at the three sites during each growing season for the study period. Surface water at the three sites can be classified as hard, with calcium carbonate concentrations exceeding 180 milligrams per liter (mg/L). Concentrations of calcium, magnesium, chloride, and dissolved solids are typical of the area. There were 68 detections of 17 pesticides, degradates, and caffeine. Atrazine and metolachlor were detected in all samples, and the atrazine degradate deethylatrazine was detected in all samples from Pine Creek and Athens & Indian Creek Drain. Another atrazine degradate (2-hydroxy-atrazine, or OIET) was detected five of the six times that it was included in the analyses. A single sample collected from Athens & Indian Creek Drain in May 2001 had relatively higher concentrations of acetochlor, atrazine, CIAT (deethylatrazine), and diuron than the other sampling sites did during the study. Analysis for various species of mercury was completed on samples collected at Pine Creek and Athens & Indian Creek Drain in July 2003, and results were similar to those typical of unimpaired streams in the Midwest. None of the surface-water sites had major ion, nutrient, or trace-element concentrations that exceeded Michigan Department of Environmental Quality standards for nonpotable surface water. USGS also collected 11 ground-water samples from 7 wells on or adjacent to the traditional reservation in 2003. Two wells were sampled twice, and a single well was sampled three times, in order to document any chemical changes that might have occurred as a result of aquifer recharge, which most typically occurs in late winter to spring in the southern Lower Peninsula of Michigan. Samples were analyzed for 184 pesticides and degradates and caffeine. There were five detections of four pesticides or degradates, but none of the detected chemicals are included in current U.S. Environmental Protection Agency drinking-water standards. The remaining 181 analytes were below laboratory reporting limits.

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Water resources data, Oakland County, Michigan 2001-2004

The U.S. Geological Survey (USGS), in cooperation with Oakland County, the Huron-Clinton Metropark Authority, the Michigan Department of Environmental Quality (MDEQ), and the Rouge Program Office, collected streamflow, water-quality, and ground-water-level data in watersheds across Oakland County during water years 2001, 2002, 2003, and 2004. Water years begin October 1 and end September 30. This report presents water resources data used to produce a series of interpretive reports on the quantity and quality of water in Oakland County for Oakland County, Michigan. Some of these data have been published elsewhere, but are provided here in one report. This report has two main sections. The first section provides an overview of the methods used to collect the various types of data. The second section is a series of data tables containing ground-water-level data, synoptically measured stream-water-quality data, synoptically measured lake-water-quality data, and the results of a macroinvertebrate and habitat assessment.

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Simulation of ground-water flow and areas contributing ground water to production wells, Cadillac, Michigan

Ground water is the primary source of water for domestic, municipal, and industrial use within the northwest section of Michigan's Lower Peninsula. Because of the importance of this resource, numerous communities including the city of Cadillac in Wexford County, Michigan, have begun local well-head protection programs. In these programs, communities protect their ground-water resources by identifying the areas that contribute water to production wells, identifying potential sources of contamination, and developing methods to cooperatively manage and minimize threats to the water supply. The U.S. Geological Survey, in cooperation with the city of Cadillac, simulated regional ground-water flow and estimated areas contributing recharge and zones of transport to the production well field. Ground-water flow models for the Clam River watershed, in Wexford and Missaukee Counties, were developed using the U.S. Geological Survey modular three-dimensional finite-difference ground-water flow model (MODFLOW 2000). Ground-water flow models were calibrated using the observation, sensitivity, and parameter estimation packages of MODFLOW 2000. Ground-water-head solutions from calibrated flow models were used in conjunction with MODPATH, a particle-tracking program, to simulate regional ground-water flow and estimate areas contributing recharge and zones of transport to the Cadillac production-well field for a 10-year period. Model simulations match the conceptual model in that regional ground-water flow in the deep ground-water system is from southeast to northwest across the watershed. Areas contributing water were determined for the optimized parameter set and an alternate parameter set that included increased recharge and hydraulic conductivity values. Although substantially different hydrologic parameters (assumed to represent end-member ranges of realistic hydrologic parameters) were used in alternate numerical simulations, simulation results differ little in predictions of the size of the contributing area to the city well field. However, increasing recharge and hydraulic conductivity values appreciably affected the shape of the contributing area and zone of contribution of reacharge. Simulation results indicate that the region immediately to the south and southeast of the well field is contributing water to the production wells. Detailed aquifer characterization would be needed to describe and simulate

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Water resources in a rapidly growing region: Oakland County, Michigan

Oakland County is a suburban county in southeast Michigan. Population and demand for water grew steadily in the county over the 20th century, and these trends are expected to continue in coming decades. Roughly 75 percent of current water demand is met by imported water from the Detroit Water and Sewerage Division (DWSD), but water use from ground-water sources within the county still exceeds 43 million gallons per day. Because much of the population growth is in areas beyond the DWSD system, an additional 20-25 million gallons per day of supply may be necessary to meet future demands. Managing the wastewater produced while also protecting human and ecosystem health also may present challenges. Despite considerable expansion of urban areas, streamflow characteristics at most sites have not been affected. However, at several sites in areas of the county that are both supplied by ground water and sewered, statistically significant downward trends in low-flow stream discharges have been noted between 1970 and 2003. Stream chemistry, compared to a previous study of county water resources prepared in 1972, has generally improved, with marked decreases in concentrations of nitrogen, phosphorus, and sulfate. Chloride concentrations, however, have increased dramatically in river and lake water across the county. Detectable concentrations of personal-care products, flame retardants, and petroleum fuel compounds were identified at all river sites sampled.

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Simulation of ground-water flow and areas contributing ground water to production wells, Cadillac, Michigan

Ground water is the primary source of water for domestic, municipal, and industrial use within the northwest section of Michigan's Lower Peninsula. Because of the importance of this resource, numerous communities including the city of Cadillac in Wexford County, Michigan, have begun local wellhead protection programs. In these programs, communities protect their ground-water resources by identifying the areas that contribute water to production wells, identifying potential sources of contamination, and developing methods to cooperatively manage and minimize threats to the water supply. The U.S. Geological Survey, in cooperation with the city of Cadillac, simulated regional ground-water flow and estimated areas contributing recharge and zones of transport to the production well field. Ground-water flow models for the Clam River watershed, in Wexford and Missaukee Counties, were developed using the U.S. Geological Survey modular three-dimensional finite-difference ground-water flow model (MODFLOW 2000). Ground-water flow models were calibrated using the observation, sensitivity, and parameter estimation packages of MODFLOW 2000. Ground-water-head solutions from calibrated flow models were used in conjunction with MODPATH, a particle-tracking program, to simulate regional ground-water flow and estimate areas contributing recharge and zones of transport to the Cadillac production-well field for a 10-year period. Model simulations match the conceptual model in that regional ground-water flow in the deep ground-water system is from southeast to northwest across the watershed. Areas contributing water were determined for the optimized parameter set and an alternate parameter set that included increased recharge and hydraulic conductivity values. Although substantially different hydrologic parameters (assumed to represent end-member ranges of realistic hydrologic parameters) were used in alternate numerical simulations, simulation results differ little in predictions of the size of the contributing area to the city well field. However, increasing recharge and hydraulic conductivity values appreciably affected the shape of the contributing area and zone of contribution of reacharge. Simulation results indicate that the region immediately to the south and southeast of the well field is contributing water to the production wells. Detailed aquifer characterization would be needed to describe and simulate the heterogeneous glacial deposits in the watershed.

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A pre-dam-removal assessment of sediment transport for four dams on the Kalamazoo River between Plainwell and Allegan, Michigan

Four dams on the Kalamazoo River between the cities of Plainwell and Allegan, Mich., are in varying states of disrepair. The Michigan Department of Environmental Quality (MDEQ) and U.S. Environmental Protection Agency (USEPA) are considering removing these dams to restore the river channels to pre-dam conditions. This study was initiated to identify sediment characteristics, monitor sediment transport, and predict sediment resuspension and deposition under varying hydraulic conditions. The mathematical model SEDMOD was used to simulate streamflow and sediment transport using three modeling scenarios: (1) sediment transport simulations for 730 days (Jan. 2001 to Dec. 2002), with existing dam structures, (2) sediment transport simulations based on flows from the 1947 flood at the Kalamazoo River with existing dam structures, and (3) sediment transport simulations based on flows from the 1947 flood at the Kalamazoo River with dams removed. Sediment transport simulations based on the 1947 flood hydrograph provide an estimate of sediment transport rates under maximum flow conditions. These scenarios can be used as an assessment of the sediment load that may erode from the study reach at this flow magnitude during a dam failure. The model was calibrated using suspended sediment as a calibration parameter and root mean squared error (RMSE) as an objective function. Analyses of the calibrated model show a slight bias in the model results at flows higher than 75 m 3 /s; this means that the model-simulated suspended-sediment transport rates are higher than the observed rates; however, the overall calibrated model results show close agreement between simulated and measured values of suspended sediment. Simulation results show that the Kalamazoo River sediment transport mechanism is in a dynamic equilibrium state. Model results during the 730-day simulations indicate significant sediment erosion from the study reach at flow rates higher than 55 m 3 /s. Similarly, significant sediment deposition occurs during low to average flows (monthly mean flows between 25.49 m 3 /s and 50.97 m 3 /s) after a high-flow event. If the flow continues to stay in the low to average range the system shifts towards equilibrium, resulting in a balancing effect between sediment deposition and erosion rates. The 1947 flood-flow simulations show approximately 30,000 m 3 more instream sediments erosion for the first 21 days of the dams removed scenario than for the existing-dams scenario, with the same initial conditions for both scenarios. Application of a locally weighted regression smoothing (LOWESS) function to simulation results of the dams removed scenario indicates a steep downtrend with high sediment transport rates during the first 21 days. In comparison, the LOWESS curve for the existing-dams scenario shows a smooth transition of sediment transport rates in response to the change in streamflow. The high erosion rates during the dams-removed scenario are due to the absence of the dams; in contrast, the presence of dams in the existing-dams scenario helps reduce sediment erosion to some extent. The overall results of 60-day simulations for the 1947 flood show no significant difference in total volume of eroded sediment between the two scenarios, because the dams in the study reach have low heads and no control gates. It is important to note that the existing-dams and dams-removed scenarios simulations are run for only 60 days; therefore, the simulations take into account the changes in sediment erosion and deposition rates only during that time period. Over an extended period, more erosion of instream sediments would be expected to occur if the dams are not properly removed than under the existing conditions. On the basis of model simulations, removal of dams would further lower the head in all the channels. This lowering of head could produce higher flow velocities in the study reach, which ultimately would result in accelerated erosion rates.

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Effects of urban land-use change on streamflow and water quality in Oakland County, Michigan, 1970-2003, as inferred from urban gradient and temporal analysis

Various adverse hydrologic effects on streams have been attributed to urban development and expanded impervious surface area, including increased high flows, decreased low flows, increased variability (commonly referred to as flashiness), nutrient enrichment, and increased dissolved solids concentrations. These effects are often observed through the use of urban-gradient studies, which compare hydrologic characteristics among watersheds with different levels of development. This technique is frequently applied when comparable prior data are not available for the watersheds of interest. During 1966 - 1970, and again during 2001 - 2003, the U.S. Geological Survey collected a series of low-flow water-chemistry samples. Streamflow-gaging stations were operated throughout the period from 1966- 2003 as part of ongoing monitoring operations. This study compares these two water-quality data sets; tests the streamflow data for trends in high flows, low flows, and flashiness; and correlates 2000 land use with water-quality and streamflow data collected during the 2001 - 2003 study. Despite substantial change in land use during 1980 - 2000, with urban land covers replacing open space, forest, and agriculture, little evidence is found in the time-series data of alteration of the daily streamflow characteristics or nutrient enrichment in the study watersheds. However, a distinct shift is observable in chloride concentrations. Strong positive correlations exist across the urban gradient between development and increased peak flows as well as between development and increased flashiness. Correlations of water-quality data to development metrics show strong positive correlations with increased dissolved solids and salt content, as well as increased concentrations of fecal indicator bacteria ( Eschericia coli ). This apparent contradiction may be caused by the differences in the changes measured in each analysis. The change-through-time approach describes change from a fixed starting point of approximately 1970; the gradient approach describes the cumulative effect of all change up to approximately 2000. These findings indicate that although urbanization in Oakland County results in most of the effects observed in the literature, as evidenced in the gradient approach, relatively few of the anticipated effects have been observed during the past three decades. This relative stability despite rapid land-cover change may be related to efforts to mitigate the effects of development and a general decrease in the density of new residential development. It may also be related to external factors such as climate variability and reduced atmospheric deposition of specific chemicals.

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Historical and simulated changes in channel characteristics of the Kalamazoo River, Plainwell to Otsego, Michigan

In a study to understand the historical effects of the construction and decommissioning of dams on the Kalamazoo River, Plainwell to Otsego, Michigan, and to simulate channel changes that may result if the dams were removed, early to mid-1800s General Land Office surveys and aerial photographs from 1938, 1981, and 1999 were compared in order to identify historical changes in the river’s planform. This analysis of the 80-mile reach from Morrow Dam to the river mouth at Saugatuck provided insight into how susceptible the river has been to channel migration. The comparison showed that changes in channel width and location were caused mainly by construction of dams and subsequent water-level adjustments in the impounded reaches upstream from the dams. Braiding also occurred downstream from one of the dams. Minor changes in channel form that were not caused by the dams, such as the development and cutoff of meander bends, were observed. A more detailed study in a 5-mile reach passing through the Plainwell and Otsego City Dams included compiling existing valley cross section and longitudinal profile data into a database, assessing bank stability, and using a hydrologic model to simulate the channel as if the dams were removed. Fifty-four valley cross sections compiled from United States Geological Survey and consultant data sets were used as a base for a bank-stability assessment and to design a hypothetical stable channel without the two dams. The channel design involved adjusting the slope, hydraulic geometry, and floodplain width to ensure that water could be transferred through the reach without increasing flooding or erosion problems. The bank-stability assessment focused on conditions that are critical to failure. This was accomplished through the use of a two step process. The first involved evaluating the sediment removed from the bank toe when the stage is high. The second involved calculating the factor of safety for the bank based on the water table being elevated higher than the stage, mimicing a bank storage effect. Using these paired proccesses, two scenarios of critical conditions were evaluated: dams present and dams removed. Results of the bank assessments showed that, under both critical-condition scenarios, the streambanks were more susceptible to toe erosion than to block failure. As toe erosion progresses, the banks will eventually collapse as supporting material underneath is removed. Toe erosion for the damsremoved scenario resulted in higher amounts of erosion than for the dams-present scenario, leading to an overall decrease in bank stability. Effects of vegetation on the bank stability were variable; stability for some banks increase if vegetation was present but remain the same for other banks.

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Preliminary survey of antibiotic-resistant fecal indicator bacteria and pathogenic Escherichia coli from river-water samples collected in Oakland County, Michigan, 2003

A preliminary study was done in Oakland County, Michigan, to determine the concentration of fecal indicator bacteria (fecal coliform bacteria and enterococci), antibiotic resistance patterns of these two groups, and the presence of potentially pathogenic Escherichia coli ( E. coli ). For selected sites, specific members of these groups [ E. coli , Enterococcus faecium ( E. faecium ) and Enterococcus faecalis ( E. faecalis )] were isolated and tested for levels of resistance to specific antibiotics used to treat human infections by pathogens in these groups and for their potential to transfer these resistances. In addition, water samples from all sites were tested for indicators of potentially pathogenic E. coli by three assays: a growth-based assay for sorbitol-negative E. coli , an immunological assay for E. coli O157, and a molecular assay for three virulence and two serotype genes. Samples were also collected from two non-urbanized sites outside of Oakland County. Results from the urbanized Oakland County area were compared to those from these two non-urbanized sites. Fecal indicator bacteria concentrations exceeded State of Michigan recreational water-quality standards and (or) recommended U.S. Environmental Protection Agency (USEPA) standards in samples from all but two Oakland County sites. Multiple-antibiotic-resistant fecal coliform bacteria were found at all sites, including two reference sites from outside the county. Two sites (Stony Creek and Paint Creek) yielded fecal coliform isolates resistant to all tested antibiotics. Patterns indicative of extended-spectrum-β-lactamase (ESBL)- producing fecal coliform bacteria were found at eight sites in Oakland County and E. coli resistant to clinically significant antibiotics were recovered from the River Rouge, Clinton River, and Paint Creek. Vancomycin-resistant presumptive enterococci were found at six sites in Oakland County and were not found at the reference sites. Evidence of acquired antibiotic resistances was detected in bacteria from multiple sites in Oakland County but not detected in bacteria from the reference sites. Integrons capable of transferring resistance were detected in isolates from the River Rouge and Clinton River. E. faecium and E. faecalis identified in samples collected from Kearsley Creek and Evans Ditch were resistant to high levels of vancomycin and carried transferable genes responsible for resistance. Several sites in Oakland County had indicators of pathogenic E. coli in August and (or) September 2003. Two samples from the Clinton River in August tested positive for all three E. coli O157 tests. Both the August and September samples from one River Rouge site were positive for the immunological and molecular assay for E. coli O157. A combination of virulence genes commonly associated with human illness was detected at five sites in August and seven sites in September. Antibiotic-resistance profiles of clinical concern along with genes capable of transferring the resistance were found at several sites throughout Oakland County; samples from many of these sites also contained potentially pathogenic E. coli .

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Changes in streamflow patterns related to hydrologic restoration of a sedge fen wetland in Seney National Wildlife Refuge, Michigan, 1998-2004

Vast expanses of sedge fen in Schoolcraft County in Michigan's Upper Peninsula were ditched and diked in the early to mid-1900s to promote agricultural development and create waterfowl habitat. Unintended consequences of these actions were far reaching and included the deposition of large amounts of sand in the Manistique River. In 2002, the U.S. Fish and Wildlife Service, which now manages much of the wetland as part of Seney National Wildlife Refuge, attempted to restore streamflow to Walsh Creek and overland flow downgradient of Walsh Ditch, near C-3 Pool. Streamflow data were collected before and after remediation activities. These data indicate that efforts to restore flow to Walsh Creek were partially successful, but it is unclear whether overland flow was restored downgradient from Walsh Ditch. Alternatives for future evaluation of restoration of flow to Walsh Creek include monitoring streamflow at three easily accessible locations. Restoration of overland flow downgradient from Walsh Ditch can be assessed in the future by monitoring flows at three additional sites. Restoration of either site can be assessed by monitoring vegetation shifts, possibly with aerial or satellite imagery.

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Trends in surface-water quality at selected National Stream Quality Accounting Network (NASQAN) stations, in Michigan

To demonstrate the value of long-term, water-quality monitoring, the Michigan Department of Environmental Quality (MDEQ), in cooperation with the U.S. Geological Survey (USGS), initiated a study to evaluate potential trends in water-quality constituents for selected National Stream Quality Accounting Network (NASQAN) stations in Michigan. The goal of this study is to assist the MDEQ in evaluating the effectiveness of water-pollution control efforts and the identification of water-quality concerns. The study included a total of nine NASQAN stations in Michigan. Approximately 28 constituents were analyzed for trend tests. Station selection was based on data availability, land-use characteristics, and station priority for the MDEQ Water Chemistry Monitoring Project. Trend analyses were completed using the uncensored Seasonal Kendall Test in the computer program Estimate Trend (ESTREND), a software program for the detection of trends in water-quality data. The parameters chosen for the trend test had (1) at least a 5-year period of record (2) about 5 percent of the observations censored at a single reporting limit, and (3) 40 percent of the values within the beginning one-fifth and ending one-fifth of the selected period. In this study, a negative trend indicates a decrease in concentration of a particular constituent, which generally means an improvement in water quality; whereas a positive trend means an increase in concentration and possible degradation of water quality. The results of the study show an overall improvement in water quality at the Clinton River at Mount Clemens, Manistee River at Manistee, and Pigeon River near Caseville. The detected trend for these stations show decreases in concentrations of various constituents such as nitrogen compounds, conductance, sulfate, fecal coliform bacteria, and fecal streptococci bacteria. The negative trend may indicate an overall improvement in agricultural practices, municipal and industrial wastewater-treatment processes, and effective regulations. Phosphorus data for most of the study stations could not be analyzed because of the data limitations for trend tests. The only station with a significant negative trend in total phosphorus concentration is the Clinton River at Mount Clemens. However, scatter-plot analyses of phosphorus data indicate decreasing concentrations with time for most of the study stations. Positive trends in concentration of nitrogen compounds were detected at the Kalamazoo River near Saugatuck and Muskegon River near Bridgeton. Positive trends in both fecal coliform and total fecal coliform were detected at the Tahquamenon River near Paradise. Various different point and nonpoint sources could produce such positive trends, but most commonly the increase in concentrations of nitrogen compounds and fecal coliform bacteria are associated with agricultural practices and sewage-plant discharges. The constituent with the most numerous and geographically widespread significant trend is pH. The pH levels increased at six out of nine stations on all the major rivers in Michigan, with no negative trend at any station. The cause of pH increase is difficult to determine, as it could be related to a combination of anthropogenic activities and natural processes occurring simultaneously in the environment. Trends in concentration of major ions, such as calcium, sodium, magnesium, sulfate, fluoride, chloride, and potassium, were detected at eight out of nine stations. A negative trend was detected only in sulfate and fluoride concentrations; a positive trend was detected only in calcium concentration. The major ions with the most widespread significant trends are sodium and chloride; three positive and two negative trends were detected for sodium, and three negative and two positive trends were detected for chloride. The negative trends in chloride concentrations outnumbered the positive trends. This result indicates a slight improvement in surface-water quality because chloride as a point source in natural water comes from deicing salt, sewage effluents, industrial wastes, and oil fields. For other major ions, such as magnesium and potassium, both positive and negative trends were detected. These changes in trends indicate changes in surface-water quality caused by a variety of point and non-point sources throughout Michigan, as well as natural changes in the environment.

Michigan↗

Water resources data, Michigan, water year 2004

Water resources data for the 2004 water year for Michigan consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground-water wells. This report contains discharge records for 173 streamflow-gaging stations; stage only records for 2 stream-gaging stations and 26 lake-gaging stations; stage and contents for 1 reservoir; water-quality records for 48 streamflow-gaging stations; and water-level records for 48 ground-water wells. Also included are 30 crest-stage partial-record stations. Additional water data were collected at various sites not involved in the systematic data-collection program. Miscellaneous data were collected at 117 discharge measuring sites. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State, local, and Federal agencies hi Michigan.

Michigan↗