Estuaries are partially enclosed areas where rivers meet the sea. These unique environments contain a mix of freshwater and saltwater, with constantly shifting conditions influenced by tides, river flow, and weather. The Delaware Estuary connects all of us—whether we live in Philadelphia, far upstream near Hancock, New York, or along the Bay in places like Cape May, New Jersey, or Lewes, Delaware.
Photo Credit: Shaun Bailey of PDE
people
Estuaries are essential to nearby communities. They provide drinking water, support industry and food production, and offer recreation for millions of people. The Delaware Estuary is lined with critical wetlands that filter stormwater runoff and absorb pollution before it enters rivers and bays.
More than six million people live within the region, including residents of its three major cities: Philadelphia, Camden, and Wilmington. This highly developed corridor includes the world’s largest freshwater port, the second-largest petrochemical port, and five of the East Coast’s largest refineries.
Photo Credit: Priscilla Cole
science
The Delaware Estuary faces many environmental challenges. Protecting it requires collaboration among community members, scientists, and industries. At the Partnership for the Delaware Estuary (PDE), some of our most important work focuses on research and restoration across the tidal Delaware River and Bay. See the “State of the Delaware Estuary” Report.
Photo Credit: Elizabeth Horsey of PDE
nature
Estuaries are among the most productive ecosystems on Earth, supporting more wildlife births than any other habitat type. The Delaware Estuary provides critical habitat for more than 130 species of finfish, along with clams, oysters, and crabs.
It also hosts the second-largest concentration of migrating shorebirds in the Western Hemisphere and supports habitat for 15 species of waterfowl—over half a million birds that migrate through or spend the winter here. The Estuary also contains the world’s largest population of spawning horseshoe crabs.
