Water quality, hydrology, and simulated response to changes in phosphorus loading of Mercer Lake, Iron County, Wisconsin, with special emphasis on the effects of wastewater discharges

To provide a better understanding of the factors affecting the water quality of Mercer Lake and to help guide future actions, a detailed study of the lake and its watershed was conducted by the USGS in collaboration with the Mercer Lake Association. The purposes of the study were to describe the water quality of the lake and the composition of its sediments; quantify the sources of water and phosphorus, including those associated with wastewater discharges; and evaluate the effects of past and future changes in phosphorus inputs on the water quality of the lake using eutrophication models that simulate changes in phosphorus and algae concentrations and water clarity.

Development and Application of a Groundwater/Surface-Water Flow Model using MODFLOW-NWT for the Upper Fox River Basin, Southeastern Wisconsin

The objectives for the study are to develop a baseline study of groundwater conditions and groundwater/surface-water interactions in the shallow aquifer system of the Upper Fox River Basin, develop a tool for evaluating possible alternative water-supply options for communities in Waukesha County, and contribute to the methodology of groundwater-flow modeling.

Estimation of Natural Historical Flows for the Manitowish River near Manitowish Waters, Wisconsin

The Wisconsin Department of Natural Resources is charged with oversight of dam operations throughout Wisconsin and is considering modifications to the operating orders for the Rest Lake Dam in Vilas County, Wisconsin. State law requires that the operation orders be tied to natural low flows at the dam. Because the presence of the dam confounds measurement of natural flows, the U.S. Geological Survey installed streamflow-gaging stations and developed two statistical methods to improve estimates of natural flows at the Rest Lake Dam.

Evaluation of the Effects of City of Middleton Stormwater-Management Practices on Streamflow and Water-Quality Characteristics of Pheasant Branch, Dane County, Wisconsin, 1975–2008

Over 30 years of data were used to for evaluate the effectiveness of urban stormwater-management practices by the city of Middleton, Wis. in this report. Analysis of streamflow and water-quality data collected on Pheasant Branch demonstrates the relation between the changes in the watershed to the structural and nonstructural best management practices put in place during 1975–2008. A comparison of the data from Pheasant Branch with streamflow and water-quality data collected at other nearby streams was made to assist in the determination of the possible causes of the changes in Pheasant Branch over time.

Use of Real-Time Monitoring to Predict Concentrations of Select Constituents in the Menomonee River Drainage Basin, Southeast Wisconsin, 2008–9

The Menomonee River drainage basin in southeast Wisconsin is undergoing changes that may affect water quality. Several rehabilitation and flood-management projects are underway, including removal of concrete channels and the construction of floodwater retention basins. The city of Waukesha may begin discharging treated wastewater into Underwood Creek, thus approximately doubling the current base-flow discharge. In addition, the headwater basins, historically dominated by agriculture and natural areas, are becoming increasingly urbanized.

Two new reports in the USGS Techniques and Methods Report series

Approaches in Highly Parameterized Inversion: PEST++, a Parameter ESTimation Code Optimized for Large Environmental Models

Approaches in Highly Parameterized Inversion: GENIE, a General Model-Independent TCP/IP Run Manager