Stream Biology

In Pennsylvania, the USGS's water-resources roots date back to the late 1800's, with the initiation of streamflow gaging on the Delaware and Susquehanna 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 Delaware River Basin, in cooperation with regional and local...

Fish diseases in freshwater ecosystems pose significant ecological and socioeconomic challenges; yet, monitoring them in wild populations is complex due to interactions between pathogens, hosts, and environmental conditions. External DELT (deformity, erosion, lesion, tumor, and parasite) data (fig. 1) provide a rapid and broad measure of fish health but are a relatively coarse indicator that...

USGS and partner scientists are investigating water availability, use, quality, and ecology associated with development of shale-gas energy resources in Pennsylvania.

USGS has had a cooperative program with Chester County, Pennsylvania, to measure and describe water resources since 1969. Cooperation has been primarily with the Chester County Water Resources Authority, with participation from the Chester County Health Department. This partnership provides Chester County with scientific information for water-resources management.

Issue: Per- and polyfluoroalkyl substances (PFAS) have been manufactured and used in a variety of industries in the United States since the 1940s. PFAS are ubiquitous and persistent in the environment and have the potential to have adverse human and ecological health effects. The Chesapeake Bay Program (CBP) partnerships has concerns about how PFAS will affect the Chesapeake Bay ecosystem. The CBP...