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Watersheds Research

Aerial image of the Chesapeake Bay and its tributariesNatural water resources, including bodies of water as well as their supporting watersheds, provide critical economic and social benefits to our society. The beneficial uses of many watersheds and water bodies are currently threatened by numerous factors including high levels of nutrients and sediments, habitat alteration, introduction of invasive species, toxic pollutants and land-use changes.

The protection of water systems requires a detailed understanding of how human activities affect such systems, and how the structure and function of aquatic ecosystems changes in response to those effects.

EPA works to sustain and restore natural water resources by viewing them as complex systems. In order to help sustain our precious water resources, EPA research is underway to

  • assess the condition of aquatic ecosystems;
  • obtain a complete understanding of watershed processes;
  • quantify the social, economic and environmental costs of water quality degradation;
  • establish new approaches to identify, assess and prioritize contaminant risks;
  • develop new approaches to minimize the impacts of these contaminants on water resources; and
  • consider the impacts of climate change, increased population and changing human demographics on watersheds.

Related Research

Models, Tools, and Approaches