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P.E. Hughes

Publications and source records attributed to P.E. Hughes.

9 recordsLinked to original sources
USGS1998

Partitioning and transport of total and methyl mercury in the Lower Fox River, Wisconsin

To investigate transport and partitioning processes of Hg(T) in the Fox River, we coupled detailed time series data of total mercury (Hg(T)) at the river mouth with transect sampling in the Lower Fox River. Unfiltered Hg(T) concentrations in the Fox River during the study period (April 1994-October 1995) ranged from 1.8 to 182 ng L(-1) with a median of 24.8 ng L-1, predominantly (93.6%) in the particulate phase. These levels were significantly elevated compared with other large tributaries to Lake Michigan (Hurley, J. P.; Shafer, M. M.; Cowell, S. E.; Overdier, J. T.; Hughes, P. E.; Armstrong, D. E. Environ. Sci. Technol. 1996, 30, 20932098). Transect sampling revealed progressively increasing water column Hg(T) concentrations and Hg(T) particulate enrichment downstream, which were consistent with trends in sediment Hg(T) levels in the river. Resuspended sediments are likely the predominant source of Hg from the Fox River into Green Bay. Despite elevated Hg(T) concentrations, methyl mercury (MeHg) concentrations were relatively low, suggesting limited bioavailability of Hg(T) associated with sediments.To investigate transport and partitioning processes of HgT in the Fox River, we coupled detailed time series data of total mercury (HgT) at the river mouth with transect sampling in the Lower Fox River. Unfiltered HgT concentrations in the Fox River during the study period (April 1994-October 1995) ranged from 1.8 to 182 ng L-1 with a median of 24.8 ng L-1, predominantly (93.6%) in the particulate phase. These levels were significantly elevated compared with other large tributaries to Lake Michigan. Transect sampling revealed progressively increasing water column HgT concentrations and HgT particulate enrichment downstream, which were consistent with trends in sediment HgT levels in the river. Resuspended sediments are likely the predominant source of Hg from the Fox River into Green Bay. Despite elevated HgT concentrations, methyl mercury (MeHg) concentrations were relatively low, suggesting limited bioavailability of HgT associated with sediments.

Environmental Science & Technology↗
USGS1998

Tributary loading of mercury to Lake Michigan: Importance of seasonal events and phase partitioning

As a component of a lakewide mass balance study for Lake Michigan, we measured total mercury (Hg(T)) concentrations and fluxes in 11 selected tributaries. Unfiltered Hg(T) concentrations ranged from 0.56 ng l-61 at the Pete Marquette River to 182 ng l-1 at the Fox River. Highest mean Hg(T) concentrations were observed in the Fox R., Indiana Harbor Ship Canal, Grand R. and the Kalamazoo R. Mean particulate matter Hg(T) content ranged from about 0.1 to 1.5 ??g g-1, with highest levels from the industrialized basins of the Indiana Harbor and Fox River. Highest tributary loading rates (g day-1) were observed from the Fox, Grand, Kalamazoo and St. Joseph Rivers. Increased loading rates during spring melt and summer/fall storm events in these tributaries were generally associated with particulate loading from either sediment resuspension or erosional processes. In contrast, filtered Hg(T) represented 80% of the Hg(T) flux in the Manistique R., whose watershed is comprised almost entirely of wetlands and forest.

Science of the Total Environment↗
USGS1993

Hydrologic and water-quality data for the East River Basin in northeastern Wisconsin

Hydrologic and precipitation data and water-quality samples were collected by the U.S. Geological Survey from rivers in the East River basin in northeastern Wisconsin during 1985-86. The Fox Valley Water Quality Planning Agency suspected that agricultural and urban nonpoint-source discharges were contributing significantly to the degradation of water quality in the basin. Two continuous record streamflow and waterquality gaging stations were established: one on the East River at Monroe Street in Green Bay and the other on Bower Creek at Sunnyview Road near De Pere. Streamflow for the 1986 water year was greater than twice the long-term (1967-86) average and precipitation was 33 percent greater than the long-term (1951-80) average. Average daily streamflow at the East River during the 1986 water year was 185 cubic feet per second. Average daily streamflow at Bower Creek was 6 cubic feet per second. Suspended-sediment yields were greatest in Bower Creek 264 tons per square mile per year; yields were 125 tons per square mile per year at the East River site. Total-phosphorus yields at the Bower Creek gage were 2,680 pounds per square mile per year yields were 1,130 pounds per square mile per year at the East River site. The measured yields of suspended sediment and total phosphorus from the East River site, during the 1986 water year, were significantly larger than the estimated average yields for the Fox River at Wrightstown. During a year of normal streamflow, the East River would probably contribute a maximum of 10 percent of the total suspended sediment and 9 percent of the total-phosphorus load transported to the mouth of the Fox River. Dissolved-oxygen concentrations tended to decrease upstream from the mouth of the East River. The daily mean dissolved-oxygen concentration was often less than 5 milligrams per liter at all three of the East River monitoring locations. Minimum dissolved-oxygen concentrations of 1 to 2 milligrams per liter were recorded at all sites. The acceptable fecal coliform level for recreational water quality of 200 counts per 100 milliliters was exceeded at the three East River sites and Bower Creek in more than half of the samples. More samples collected at the downstream sites on the East River at Monroe Street in Green Bay and at the Allouez Avenue bridge at Allouez contained fecal-coliform/fecal-streptococcus ratios that exceeded 4.0, indicating that the bacteria was of human origin rather than of animal. Mean concentrations for 5-day biochemical oxygen demand, total-phosphorus concentration, fecal-coliform counts, and fecal-streptococcus counts were higher at Bower Creek than any of the other sites monitored during 1985-86. Mean chlorophyll a concentrations were highest at the East River sites at Monroe Street in Green Bay and at Allouez Avenue bridge at Allouez.

Wisconsin↗
USGS1993

Concentrations and loads of polychlorinated biphenyls in major tributaries entering Green Bay, Lake Michigan, 1989-90

The U.S. Geological Survey collected water samples from the five major tributaries to Green Bay, Lake Michigan, to determine the load of total polychlorinated biphenyls (RGB's) entering the bay. These samples were collected from January 1989 through early May 1990 from the Escanaba, Menominee, Peshtigo, Oconto, and Fox Rivers. Sampling sites were located near the mouth of each river and also just upstream of De Pere dam on the Fox River. Water samples were collected for analysis of total, dissolved, and particulate concentrations of PCB's at the nanogram-per-liter level. Loads of PCB's entering Green Bay were computed using a total-integration method. The methods used to collect water samples and compute the loads of total PCB's entering the bay are described in this report. Graphs showing total PCB's concentrations and loads are presented for each site, along with the corresponding data tables. These data indicate that the amount of total PCB's entering the bay from the Fox River is greater than from all other major tributaries combined.

Wisconsin↗
USGS1993

Water quality of an urban wet detention pond in Madison, Wisconsin, 1987-88

A 5,670-sq m wet detention pond was monitored by the U.S. Geological Survey to determine its effect on the water quality of urban runoff. The pond has a drainage area of 0.96-sq km, composed primarily of single-family residential land use. Event-mean concentrations (EMC) were determined from samples collected for sediment, nutrients, and selected metals at the pond's inflow and outflow sites. EMC samples were collected for 64 runoff events during the study period from February 1987 to April 1988. Storm precipitation ranged from 1 to 51 mm during these events. Inflow and outflow EMC and constituent loads were compared to determine the trap efficiency of the pond. Trap efficiency varied considerably among water-quality constituents. In general, the detention pond decreased the EMC of sampled constituents at the outlet compared to the inlet. The median decrease in EMC for suspended solids was 88 percent, 60 percent for total chemical oxygen demand (COD), 43 percent for total phosphorus, 38 percent for total Kjeldahl nitrogen, 65 percent for total nitrite plus nitrate, and 71 percent for total lead. A notable exception to the general decrease in EMC is for chloride. The EMC for chloride was generally higher in outflow from the pond than in the inflow. This is attributed to an unmonitored influx of chloride to the pond during the winter that subsequently was flushed out during monitored runoff events. The total study-period loads of most constituents were less leaving the pond than the loads entering it. This decrease is attributed to the constituents transported on suspended sediment being deposited in the pond. The decrease in total load of suspended solids was 88 percent, 62 percent for total COD, 58 percent for total phosphorus, 46 percent for total Kjeldahl nitrogen, 62 percent for total nitrite plus nitrate, 97 percent for total copper, and 93 percent for total lead. (USGS)

Wisconsin↗
USGS1993

Hydrology, water quality, trophic status, and aquatic plants of Fowler Lake, Wisconsin

The U.S. Geological Survey, in cooperation with the Fowler Lake Management District, completed a hydrologic and water-quality study of Fowler Lake in southeastern Wisconsin during calendar year 1984. Data on temperature, pH, specific conductance, and concentrations of dissolved oxygen, total phosphorus, dissolved orthophosphate phosphorus, and various nitrogen species were collected from January through November 1984. The water-quality data indicate that Fowler Lake can be classified as a mildly fertile lake with excellent water clarity as indicated by Secchi depth readings generally greater than 12 feet. Although phosphorus concentrations are generally less than 0.01 milligram per liter, the lake does produce dense stands of macrophytes during the open-water period. The lake is thermally stratified during the summer months, resulting in oxygen depletion in the deepest parts of the lake. The average hydraulic residence time for Fowler Lake during 1984 was 6.9 days, which is substantially less than the 305 days for upstream Okauchee Lake or the 145 days for downstream Lac La Belle. Precipitation during 1984 was about 27 percent higher than normal and streamflows in the area were about 55 percent higher than normal. The Oconomowoc River contributed 98 percent of the inflow and 88 percent of the phosphorus load to Fowler Lake. The low annual phosphorus input (28 pounds per square mile) to the lake from the Oconomowoc River shows the benefit of upstream lakes on the Oconomowoc River. Fourteen percent of the phosphorus input load to Fowler Lake is deposited in the lake sediments and the rest is transported through the lake by surface-water flow to downstream Lac La Belle. Dense growths of macrophytes in the lake change in composition seasonally; chara sp. (muskgrass) and Myriophyllum sp. (milfoil) are abundant in June and Najas marina and Vallesneria Americana (wild celery) are abundant in August.

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↗