Regions or areas bounded by drainage divides and occupied by drainage systems; specifically the tract of country that gathers water originating as precipitation and contributes it to a particular stream channel or system of channels, or to a lake, reservoir, or other body of water. [Glossary of Geology, 4th ed.]
Program to compile data from the National Water-Quality Assessment Program study units to study national trends with links to sediment coring sites, video on Salt Lake City, study units identification, and publications.
Data warehouse for national water quality program with links to chemical, biological, and physical data for water, sediment and animal tissues, nutrient, pesticide, and VOC levels, streamflow, and ground water levels from national study units.
Reports concentration of organic compounds here, to serve as a baseline against which future measurements can be compared and to provide a general assessment of the quality of local water treatment efforts.
Measured concentrations of many compounds in water people use. Some compounds are regulated as health hazards; a few of these were over the benchmark limits. Others may become issues of concern, so studies such as this give us helpful background levels.