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Water Quality

The Center measures, analyzes, and predicts the water quality of surface water and groundwater. We collect and analyze automated continuous data and collect water samples for lab analysis. These data help us detect, quantify, and explain changes to water quality over time, understand how natural conditions and human activities affect water quality, and predict water quality in unsampled areas.

Learn more about the water quality team

Realtime Water Quality Data

Map of USGS stream gage sites in Maryland, Delaware, and Washington DC.

Explore real-time streamflow, groundwater, and water-quality conditions and access data for MD, DE, and DC.

Realtime MD-DE-DC Dashboard

Download Discrete Sampling Data

Hydrologic technician Fisseha Mengistu reels in a sampling bottle.

Download discrete sampling data from USGS monitoring sites.

Discrete sample data are derived from manual field collection and laboratory analyses and include water quality, sediment, biological, air and soil samples from thousands of monitoring locations across the United States and related territories.

Discrete Sampling Data

Water Data for the Nation

Screenshot of the Water Data for the Nation homepage highlighting 6 core ways to interact with USGS water data

Find USGS data and tools relevant to a wide range of water resources and conditions including streamflow, groundwater, water quality, and water use and availability.

Get Water Data
Filter Total Items: 4
Water flows out of a bioreactor through a white PVC pipe before splashing down into a small stream.

Monitoring the Effectiveness of Conservation Practices in Small Agricultural Watersheds

Farmers are an important part of the economy and heritage of the Chesapeake Bay. Farmers also act as stewards of the land and water. Across the Chesapeake Bay Watershed, members of the agricultural community are volunteering to adopt conservation practices on their land. The goal of these practices is to protect the health of the soil, local streams and rivers, and the Chesapeake Bay. These...
By
Chesapeake Bay Activities, Maryland-Delaware-D.C. Water Science Center, Pennsylvania Water Science Center, Virginia and West Virginia Water Science Center
Monitoring the Effectiveness of Conservation Practices in Small Agricultural Watersheds

Monitoring the Effectiveness of Conservation Practices in Small Agricultural Watersheds

Farmers are an important part of the economy and heritage of the Chesapeake Bay. Farmers also act as stewards of the land and water. Across the Chesapeake Bay Watershed, members of the agricultural community are volunteering to adopt conservation practices on their land. The goal of these practices is to protect the health of the soil, local streams and rivers, and the Chesapeake Bay. These...
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Corn field in front of barn, silo, and houses

New study evaluates effects of agricultural conservation practices on nitrogen in streams of the Chesapeake Bay

Issue: Adaptive management in support of Chesapeake Bay restoration is complicated by uncertainty about the effects of agricultural management practices on water quality. Despite increasing investment, effects of agricultural conservation practices on regional water quality remain difficult to quantify due to factors such as groundwater travel times, varying modes-of-action, and the general lack...
By
Chesapeake Bay Activities, Maryland-Delaware-D.C. Water Science Center
New study evaluates effects of agricultural conservation practices on nitrogen in streams of the Chesapeake Bay

New study evaluates effects of agricultural conservation practices on nitrogen in streams of the Chesapeake Bay

Issue: Adaptive management in support of Chesapeake Bay restoration is complicated by uncertainty about the effects of agricultural management practices on water quality. Despite increasing investment, effects of agricultural conservation practices on regional water quality remain difficult to quantify due to factors such as groundwater travel times, varying modes-of-action, and the general lack...
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Screenshot of web map and map controls; shaded areas show total phosphorus levels in Northeast US streams

2012 SPARROW Models for the Northeast: Total Phosphorus, Total Nitrogen, Suspended Sediment, and Streamflow

The 2012 SPAtially Referenced Regression On Watershed attributes (SPARROW) Models measure the damaging contaminants of phosphorus, nitrogen, and suspended sediment in streamflow throughout the Northeast United States. Through various types of watershed management practices, loads of nutrients and suspended sediment are significantly reduced within the stream network in impounded reaches, and...
By
Maryland-Delaware-D.C. Water Science Center
2012 SPARROW Models for the Northeast: Total Phosphorus, Total Nitrogen, Suspended Sediment, and Streamflow

2012 SPARROW Models for the Northeast: Total Phosphorus, Total Nitrogen, Suspended Sediment, and Streamflow

The 2012 SPAtially Referenced Regression On Watershed attributes (SPARROW) Models measure the damaging contaminants of phosphorus, nitrogen, and suspended sediment in streamflow throughout the Northeast United States. Through various types of watershed management practices, loads of nutrients and suspended sediment are significantly reduced within the stream network in impounded reaches, and...
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Standard Chlorine of Delaware Superfund Site

Bioremediation in Wetland Areas, Standard Chlorine of Delaware Inc. Superfund Site, Delaware City, Delaware

Major releases of chlorinated benzenes and benzene are known to have occurred at the Standard Chlorine of Delaware Inc. Superfund Site from 1966-2002, resulting in contamination of the groundwater underlying the site and the wetlands surrounding Red Lion Creek. Although installation of a groundwater interception and treatment system has been completed around the main facility, wetland and sediment...
By
Maryland-Delaware-D.C. Water Science Center
Bioremediation in Wetland Areas, Standard Chlorine of Delaware Inc. Superfund Site, Delaware City, Delaware

Bioremediation in Wetland Areas, Standard Chlorine of Delaware Inc. Superfund Site, Delaware City, Delaware

Major releases of chlorinated benzenes and benzene are known to have occurred at the Standard Chlorine of Delaware Inc. Superfund Site from 1966-2002, resulting in contamination of the groundwater underlying the site and the wetlands surrounding Red Lion Creek. Although installation of a groundwater interception and treatment system has been completed around the main facility, wetland and sediment...
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