Great American Megabasin: Chesapeake and Delaware

Linked by hydrology at the crossroads of American history, the Chesapeake and Delaware megabasin stretches 400 miles along the Atlantic seaboard in the most populous watershed in the United States. The American Revolutionary War and Civil War were fought along its rivers and John F. Kennedy, Richard M. Nixon, and Barack H. Obama adopted federal programs to protect its rivers and watersheds.

While sharing similar geography and climate, these contiguous mid-Atlantic basins have contrasting demographic characteristics. The Chesapeake and Delaware megabasin covers just 2% of the contiguous U.S. yet is home to 8% of the nation’s population and the nation’s fifth- and seventh-largest metropolitan economies, the U.S. Capitol, and 5 state capitals. The Chesapeake watershed (64,000 square miles) is four times larger than the Delaware (13,500 square miles) which suggests the challenges of governing the nation’s largest estuary are correspondingly complex. The Chesapeake is home to 16 million people, twice that of the Delaware basin but the Chesapeake’s population density (250 people per square mile) is less than the Delaware (590 people per square mile) which suggests less pressure per unit area from human pollution and water withdrawals.

By: Gerald J. Kauffman and Carol Collier