Basin-level habitat characteristics of selected streams in central Nebraska

Abstract

The mission of the U.S. Geological Survey (USGS) is to assess the quantity and quality of the earth resources of the Nation and to provide information that will assist resource managers and policymakers at Federal, State, and local levels in making sound decisions. Assessment of water-quality conditions and trends is an important part of this overall mission. One of the greatest challenges faced by waterresources scientists is acquiring reliable information that will guide the use and protection of the Nation's water resources. That challenge is being addressed by Federal, State, interstate, and local water-resource agencies and by many academic institutions. These organizations are collecting water-quality data for a host of purposes that include: compliance with permits and water-supply standards; development of remediation plans for specific contamination problems; operational decisions on industrial, wastewater, or watersupply facilities; and research on factors that affect water quality. An additional need for water-quality information is to provide a basis on which regionaland national-level policy decisions can be based. Wise decisions must be based on sound information. As a society we need to know whether certain types of water-quality problems are isolated or ubiquitous, whether there are significant differences in conditions among regions, whether the conditions are changing over time, and why these conditions change from place to place and over time. The information can be used to help determine the efficacy of existing waterquality policies and to help analysts determine the need for and likely consequences of new policies. To address these needs, the U.S. Congress appropriated funds in 1986 for the USGS to begin a pilot program in seven project areas to develop and refine the National Water-Quality Assessment (NAWQA) Program. In 1991, the USGS began full implementation of the program. The NAWQA Program builds upon an existing base of water-quality studies of the USGS, as well as those of other Federal, State, and local agencies. The objectives of the NAWQA Program are to: Describe current water-quality conditions for a large part of the Nation's freshwater streams, rivers, and aquifers. Describe how water quality is changing over time. Improve understanding of the primary natural and human factors that affect water-quality conditions. This information will help support the development and evaluation of management, regulatory, and monitoring decisions by other Federal, State, and local agencies to protect, use, and enhance water resources. The goals of the NAWQA Program are being achieved through ongoing and proposed investigations of 60 of the Nation's most important river basins and aquifer systems, which are referred to as study units. These study units are distributed throughout the Nation and cover a diversity of hydrogeologic settings. More than two-thirds of the Nation's freshwater use occurs within the 60 study units and more than two-thirds of the people served by public-water supply systems...

Water quality in the central Nebraska basins, Nebraska, 1992-95

“…These characteristics at a basin scale include basin shape, area, percentage of the basin contributing to runoff, the frequency and timing of floods, and land-use features [26]. Stream segment characteristics include streamflow, the shape of the channel, the stream stage at overflow into the flood plains, and sinuosity (or how curved the river is).…”

Environmental setting of Maple Creek watershed, Nebraska

“…This region was originally tall-grass prairie; however, most of the land was converted to agricultural uses after settlement (Huntzinger and Ellis, 1993). Agricultural practices dominate the study area that also includes some small rural communities and towns (Zelt, 1996). The agricultural and rural landscape that is prominent in the Maple Creek watershed is representative of the region and most of agricultural eastern Nebraska.…”

“…Maple Creek flows generally southward and eastward through the glaciated region of eastern Nebraska, which is characterized by rolling hills and incised streams. Elevations in the Maple Creek watershed range from 541 m at the upper watershed boundary (Zelt, 1996) …”

“…Zelt (1996) reported that the mean annual free-water-surface evapotranspiration, for 1956 to 1970, was about 1,100 mm, while Dugan and Zelt (2000) indicated that from 1951 through 1980, mean annual potential evapotranspiration was about 1,050 mm and mean annual actual evapotranspiration was about 500 mm.…”

Water-quality assessment of the central Nebraska basins — Entering a new decade

“…Agriculture is the dominant land use in central Nebraska (Zelt, 1996), and agricultural practices can affect the quantity and quality of water resources. For example, agricultural nonpoint sources have been linked to contamination of streams by runoff containing fecal bacteria and nutrients (that is, forms of nitrogen and phosphorus) (Nebraska Department of Environmental Quality, 2002).…”