Homepage for description of the National Stream Quality Network (NASQAN), a long-term program monitoring the concentrations and flux of sediment and chemicals in the Nation's largest rivers (Mississippi, Columbia, Colorado, Rio Grande, and Yukon).
Multiple studies addressing urban water-quality issues, to describe biological, chemical, and physical characteristics of urban water resources over time, and relate those characteristics to natural processes and human activities
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.
Trace elements are inorganic chemicals occurring in small amounts in nature. This web site of the National Water Quality Assessment links to U.S. data, publications, news, and other sites on trace metals, metalloids and radionuclides in water.
Overview of three research programs including determining levels of mercury at selected sites in water, sediment and fish, mercury emissions into the atmosphere, and mercury cycling in the Everglades National Park, Florida.
Links to online data retrieval, information on MTBE and gasoline oxygenates, VOCs analysis, VOC publications, news features, and featured online publications.
Field manual (also available in PDF and paper formats) with instructions on techniques to collect and process water samples and to perform measurements of temperature, oxygen content, conductance, pH, turbidity, and fecal contaminants.
Cooperative national project with the Federal Highway Administration (FHWA) to evaluate FHWA's guidelines for highway-runoff quality. Links to searchable online bibliography of related publications by the USGS, EPA, FHWA, and state agencies.
Distribution and characteristics of natural oil and gas seeps in California, including processes of formation and effects on the environment; with discussion of tar pits and asphaltum.
U.S. Department of the Interior |
U.S. Geological Survey