USGS Water Quality Data

USGS conducts water quality monitoring on rivers in Maryland, Delaware, and the District of Columbia, using USGS protocols that include ultra-clean techniques and a strong attention to data accuracy and precision.

Chemical and biological constituents include nutrients, trace metals, bacteria, suspended sediment, major ions, and organic wastewater compounds such as pharmaceuticals, personal-care products, and industrial compounds. For selected sites, continuous data sets exist for up to 35 years. USGS specializes in continuous water quality monitoring for physical conditions including water temperature, pH, dissolved oxygen, conductivity, and turbidity. New technology has enhanced realtime-data collection with measurements of nitrate and fluorescent dissolved organic matter (FDOM).

USGS conducts investigative studies that combine discrete and continuous water quality data to model stream processes and impacts from land use and climate change. Continuous data are also used to compute and assess status, trends, yields, and loads for nutrients and sediment. These data can be evaluated to rapidly alert public-water suppliers of events that may adversely affect water supplies.

To learn more about USGS water quality investigations, visit the USGS Water Quality Team's homepage.

Water Quality Monitoring Site Locations

You can browse a clickable map at the bottom of the page.

The map below shows the locations of USGS water-quality sites in Maryland, Delaware, and Washington, D.C.

To view information about a water-quality site, click on one of the water quality monitoring stations, represented as a yellow pentagon, on the map.

The location of surface water monitoring stations and suspended sediment monitoring stations are represented as circles and triangles respectively on the map for reference, but are not currently clickable for more information.