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Targeting the Most Impaired Watersheds

The Department of Environmental Protection (DEP) has targeted the most impaired watersheds in Pennsylvania’s Chesapeake Bay watershed where it can have the most impact by working with a variety of partners and stakeholders. A watershed is an area of land where all the water (surface and groundwater) flows to the lowest point – usually a stream, lake or river. These watersheds are determined by DEP’s 2014 Regional Agricultural Watershed Assessment Program Initiative, and 2020 Integrated Water Quality Report (303(d) list). The Integrated Water Quality Report is the result of an ongoing DEP program to assess the quality of surface waters in PA and identify streams and bodies of water that are not attaining protected uses as “impaired.”

DEP focuses state and federal funding and special attention on these watersheds in an effort to restore clean water in a designated time period by utilizing a holistic approach to all of the waters in the watershed.

Some of the factors assessed when determining the recoverability of a watershed include:

  • Level and complexity of the impairment and watershed size
  • Public water supply recharge areas for drinking water
  • Involvement and cooperation from other federal, state, and local programs and agencies,
  • Willingness of private landowners to participate,
  • Local watershed organization involvement and general public interest,
  • Ability of the local area to maintain restoration,
  • Strength of local water quality monitoring

Click on the map below to see highlights of the water quality improvement projects that have received funding support from Pennsylvania’s Growing Greener, the U.S. Environmental Protection Agency’s 319 program, and the National Fish and Wildlife Foundation (NFWF) grant funds.

For general assistance with this map, or to learn more about the programs and projects listed on the map, please contact the Division of Water Quality Standards at 717-787-9637, or send email to


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