Water-quality assessment of the Albemarle-Pamlico drainage basin, North Carolina and Virginia: Characterization of suspended sediment, nutrients, and pesticides

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 a specific contamination problem; operational decisions on industrial, wastewater, or water-supply facilities; and research on factors that affect water quality. An additional need for water-quality information is to provide a basis on which regional and 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 water-quality policies and to help analysts determine the need for, and likely consequences, of new policies. To address these needs, the 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 waterquality 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 ...

Comprehensive trend analysis of nutrients and related variables in a large eutrophic estuary: A decadal study of anthropogenic and climatic influences

“…Atmospheric wet and dry deposition (Walker et al 2000;Whitall et al 2002), groundwater (Harned et al 1995), estuarine sediments (Giffin and Corbett 2003), and partial denitrification (Glibert 1988) are all potential sources that must be addressed in future research to determine the source contributions of the striking increases in NH concentration that were docu-ϩ 4 mented in both the Neuse and Cape Fear systems, and to further evaluate the overall importance of NH in driving ϩ 4 phytoplankton production and bloom formation (Fan et al 2003).…”

Estimating Contributions of Nitrate and Herbicides From Groundwater to Headwater Streams, Northern Atlantic Coastal Plain, United States1

“…Nitrogen attributable to upland agriculture and other human sources has been reported in estuaries and nontidal tributaries of the Mid‐Atlantic region of the U.S. since at least the 1960s (Brehemer, 1964; Harned et al. , 1995; Ator et al.…”

“…Nitrogen attributable to upland agriculture and other human sources has been reported in estuaries and nontidal tributaries of the Mid-Atlantic region of the U.S. since at least the 1960s (Brehemer, 1964;Harned et al, 1995;Ator et al, 2005a). Biological productivity in most temperate estuaries is nitrogenlimited (Vitousek et al, 1997), and excess nitrogen has contributed to damaging algal blooms (Brehemer, 1964;U.S.…”

Predicted Impact and Evaluation of North Carolina's Phosphorus Indexing Tool

“…Whether the DRAINMOD method is overpredicting runoff volume on artificially drained sites or the Curve Number method is underpredicting runoff for naturally drained conditions is unknown at this time. It is interesting to note, however, that water quality studies done on the Albermarle–Pamlico Drainage Basin examining various watersheds grouped according to land use, drainage characteristics, and surficial geology have shown that the highest surface water P concentrations were observed in agricultural Coastal Plain basins with medium to poor drainage (Harned et al, 1995; McMahon and Harned, 1998). It is not known whether these increased concentrations of P in surface waters stem from P in drainage waters or surface runoff on these sites.…”