NWISWeb homepage for the National Water Information System providing access to water-resources data collected at approximately 1.5 million sites in all 50 States, the District of Columbia, and Puerto Rico.
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.
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.
Historical maps and animations of maps for monthly and annual streamflow conditions by water year showing generalized contour patterns of streamflow conditions. Maps are for the United States, Canada, and Puerto Rico.