Geology topics

Jeffrey Steuer

Publications and source records attributed to Jeffrey Steuer.

3 recordsLinked to original sources

USGS2009

Urban streams across the USA: Lessons learned from studies in 9 metropolitan areas

Studies of the effects of urbanization on stream ecosystems have usually focused on single metropolitan areas. Synthesis of the results of such studies have been useful in developing general conceptual models of the effects of urbanization, but the strength of such generalizations is enhanced by applying consistent study designs and methods to multiple metropolitan areas across large geographic scales. We summarized the results from studies of the effects of urbanization on stream ecosystems in 9 metropolitan areas across the US (Boston, Massachusetts; Raleigh, North Carolina; Atlanta, Georgia; Birmingham, Alabama; Milwaukee-Green Bay, Wisconsin; Denver, Colorado; Dallas-Fort Worth, Texas; Salt Lake City, Utah; and Portland, Oregon). These studies were conducted as part of the US Geological Survey’s National Water-Quality Assessment Program and were based on a common study design and used standard sample-collection and processing methods to facilitate comparisons among study areas. All studies included evaluations of hydrology, physical habitat, water quality, and biota (algae, macroinvertebrates, fish). Four major conclusions emerged from the studies. First, responses of hydrologic, physical-habitat, water-quality, and biotic variables to urbanization varied among metropolitan areas, except that insecticide inputs consistently increased with urbanization. Second, prior land use, primarily forest and agriculture, appeared to be the most important determinant of the response of biota to urbanization in the areas we studied. Third, little evidence was found for resistance to the effects of urbanization by macroinvertebrate assemblages, even at low levels of urbanization. Fourth, benthic macroinvertebrates have important advantages for assessing the effects of urbanization on stream ecosystems relative to algae and fishes. Overall, our results demonstrate regional differences in the effects of urbanization on stream biota and suggest additional studies to elucidate the causes of these underlying differences.

Alabama, Colorado, Georgia, Massachusetts, North C↗

USGS1997

Sources of contamination in an urban basin in Marquette, Michigan and an analysis of concentrations, loads, and data quality

The concentrations of contaminants generated from discrete source areas are critical to urban nonpoint Source Load and Management Model (SLAMM) loading calculations to Lake Superior. This study summarizes data-collection efforts during 12 storms in October 1993 and from May through August 1994, in which stormwater data were collected concurrently at 33 sites representing the eight major source areas in a 117-hectare urban basin in Marquette, Mich. For the 12 storms, commercial rooftops produced the highest geometric mean concentrations of dissolved metals such as lead (20 mg/L), zinc (263 mg/L), cadmium (0.71 mg/L), and copper (17.8 mg/L). Parking lots produced the highest concentration for all of the individual polycyclic aromatic hydrocarbon (PAH) compounds (summation equal to 64 mg/L). Residential lawns generated the highest concentrations of total kjeldahl nitrogen (9.3 mg/L) and total phosphorus (2.3 mg/L). A mass-budget approach, in which summed source area loads are compared to those measured at the basin outlet for individual storms, provided the basis for an error analysis to identify unreliable concentration data. Of the 611 concentration samples used in the mass budgets, 59 were identified as unreliable. Seventy-six percent of the unreliable samples came from collection bottles that were filled prior to the end of runoff. These full bottles may have captured a first-flush effect or acted as a sediment trap. The relative importance of an individual source-area load to the overall basin-outlet load varied according to the individual constituent. Parking lots were a major contributor of total zinc (30 percent), total cadmium (25 percent), total copper (22 percent), and all the PAH compounds (=64 percent); whereas low-traffic streets were a major producer of total suspended solids (27 percent), nitrate plus nitrite (21 percent), and total cadmium (25 percent). Grass areas were a major producer of total kjeldahl nitrogen (31 percent) and total phosphorus (26 percent), even though the water volume generated from grass areas was low (5.8 percent of the total water volume generated).

Michigan↗

USGS1995

Long-term simulation of PCB export from the Fox River to Green Bay

A mass balance approach was used to model long-term PCB transport in the Fox River (Wisconsin) from Lake Winnebago to Green Bay. The objectives of this research were to (1) extend the modeling approach for the Fox River to permit realistic long-term simulations of contaminant transport and fate, (2) forecast long-term PCB export from the Fox River to Green Bay, and (3) develop a rational approach for evaluating sediment remediation alternatives. Field data collected as part of the Green Bay Mass Balance Study during 1988-90 and additional data collected by the Wisconsin Department of Natural Resources and the U.S. Geological Survey during 1992-93 were used to develop the model. A 10-year hindcast was conducted to confirm long-term model predictions. A series of 25-year forecasts were then conducted to explore the potential effects of hydrograph structure, extremely high flows, and sediment remediation on long-term PCB export from the Fox River to Green Bay. PCB export from the Fox River is forecast to decrease, and most (75%) of the PCB reservoir in Fox River sediment is expected to remain in place. However, extremely high flows in future years are forecast to cause significant PCB resuspension and export. Model forecasts suggest that long-term PCB export is only mildly sensitive to changes in hydrograph structure. Sediment remediation is forecast to reduce but not eliminate PCB export.

Wisconsin↗