Factors Affecting Water Quality

Through collaboration and coordination, USGS research helps preserve and restore America’s most iconic landscapes. We apply insights across ecosystems to understand how these systems function and change, helping natural resource managers protect our Nation’s natural heritage for generations to come.

As a home to 18 million people and a destination for countless visitors seeking recreational opportunities, the health of the Chesapeake Bay watershed is of critical importance. The U.S. Geological Survey (USGS) is a leading provider of data-driven insights about the condition of the watershed’s lands, waters, fish, and wildlife. These insights and our collaborative work with partners throughout...

USGS provides monitoring, analysis, modeling and research on streams and water quality to better understand the fate and transport of nutrients and sediment to the Susquehanna and other rivers, and their tributaries, and eventually to the Chesapeake Bay. Additional research focuses on emerging contaminants and other stressors that effect human and aquatic life in the watershed and estuary.

The findings of this study show that salinity is elevated above background levels throughout most freshwater streams within the Chesapeake Bay watershed. This information can help prioritize salt management strategies for local streams and rivers.

The wide and majestic Susquehanna River is one of the oldest rivers in the world and provides water for over 4 million people. Despite its beauty, the Susquehanna River and the Chesapeake Bay downstream has been facing the detrimental effects of excess nutrients (nitrogen and phosphorus).

Wastewater treatment plant discharges can be a source of organic contaminants, including pesticides, to rivers. Pesticide concentrations were predicted based on wastewater percentages in stream water using a modeling tool, and verified with measured concentrations to identify other potential landscape sources.

Per- and polyfluoroalkyl substances (PFAS) are a large group of chemicals that have been recognized as concerns for both human and ecosystem health. There is a need to understand the effects of PFAS on fish health and populations.

In Pennsylvania, the USGS's water-resources roots date back to the late 1800's, with the initiation of streamflow gaging on the Susquehanna and Delaware Rivers and assessments of groundwater resources near Philadelphia. The USGS Pennsylvania Water Science Center continues to provide scientific information about the water resources of the Susquehanna River Basin, in cooperation with regional and...

USGS is working with federal, state and local partners to develop multiple assessments of stream and river conditions in non-tidal areas of the Chesapeake Bay watershed. These assessments will help managers preserve stream health and improve biological conditions in impaired streams as the human population and climate continue to change in this region.

USGS conducted synoptic sampling of major-ion chemistry and the nitrogen and oxygen isotopic composition of nitrate in Fishing Creek during base flow to evaluate the occurrence and distribution of nutrients and to characterize biogeochemical processes.

Stream ecosystems support vital resources that may be jeopardized by climate change and climate stressors such as drought.

The findings of the study highlight that management practices can have both hidden costs and benefits to fish and macroinvertebrates depending on regional and local factors like how many and what type of management practices are implemented.