Nutrients

Permeable pavement is a porous urban surface which catches precipitation and surface runoff, storing it in the reservoir while slowly allowing it to infiltrate into the soil below. This study will evaluate how well different types of permeable pavement reduces the amount of pollutants and runoff volume.

Many Dane County, Wis., streams and lakes have been degraded due to excessive nutrients and sediment contributed primarily by agriculture and urbanization. The goal is to build a long-term base of streamflow, lake stage, and water-quality data essential for water-resource planning and assessment purposes for streams and lakes in Dane County, with a focus on the Yahara River Basin.

The USGS is cooperating with Discovery Farms to understand agriculture’s impact on the environment and help producers find ways to minimize their impact while remaining economically viable. Edge-of-field or subsurface tile monitoring stations measure runoff-event volume, including snowmelt, and collect samples which are analyzed for suspended sediment, phosphorus, nitrogen, and chloride.

In support of the Michigan Department of Environmental Quality (MDEQ) Water Chemistry Monitoring Project, the USGS Michigan Water Science Center has been collecting long-term water quality data for Michigan's rivers and streams.

SPARROW models for the Great Lakes, Ohio River, Upper Mississippi River, and Red River Basins predict long-term mean annual loads, yields, concentrations, and source contributions of water, nitrogen, phosphorus, and sediment throughout the Midwest.

The Upper Pecatonica River pilot project is testing targeted water-quality improvement strategies in small agricultural watersheds. The USGS is contributing by monitoring phosphorus and sediment at the watershed outlets, quantifying in-stream sources and sinks of phosphorus and sediment, and developing innovative approaches for quantifying sediment-related stream impairments and TMDLs.

Green Lake is the deepest natural inland lake in Wisconsin. Through time its water quality has degraded, with relatively high phosphorus concentrations and zones of hypoxia. This project is quantifying the water quality of the lake and its tributaries, and it will provide information to help guide efforts to improve the lake.

Eutrophication of Delavan Lake accelerated from the 1940s to 1980s, resulting in a hypereutrophic lake with severe blue-green algae blooms. Extensive rehabilitation efforts were implemented to improve water quality. The USGS measured nutrients, suspended sediment, water quality, and plankton populations to quantify the effectiveness of rehabilitation efforts and guide future management decisions.

To reduce the impact of increasing urban development and recreational use on Geneva Lake, efforts are being made to decrease point- and nonpoint-source pollution inputs. To document Geneva Lake's water quality, the USGS collected water-quality data and developed empirical eutrophication models to demonstrate that reductions in phosphorus loading were related to water-quality improvements.

The USGS is evaluating the effectiveness of non-point pollution control measures in five watersheds in the Lower Fox River and Duck Creek watersheds and comparing daily phosphorus and suspended solids loads for each watershed.

SPARROW models for the Mississippi/Atchafalaya River Basin (MARB) predict long-term average loads, concentrations, yields, and source contributions of water, nitrogen, phosphorus, and suspended sediment to the Gulf of Mexico.

SPARROW phosphorus and nitrogen models are being developed for the entire Great Lakes Basin and the Upper Midwest part of the U.S., and the Red and Assiniboine River Basin, as part of a Binational project between the USGS and the International Joint Commission (IJC) and National Research Council (NRC) of Canada.