The Chesapeake Bay invokes many thoughts. Some people think of oysters,crabs, or rockfish. Others think of migratory waterfowl, recreational sailing, watermen, or maritime history. The images vary because the Chesapeake Bay is a big place that has attracted the attention of people for a variety of reasons for many thousands of years. The region's resources and stories are even more diverse when one considers not only the Bay but also its vast drainage area or watershed. .

The Bay is the largest estuary in the United States and is one of the largest in the World. The Bay today covers a surface area of 2500 square miles. That's a little bigger than the state of Delaware. Its upper end starts at the mouth of the Susquehanna River at Havre de Grace, Maryland in the north. Its southern outlet into the Atlantic Ocean is between Cape Henry and Cape Charles, Virginia. Fresh river water mixes with salty ocean currents within the long, narrow 200 mile-long estuary which is forty miles wide at its broadest point, creating a rich environment for both plant and animal life.

The Chesapeake Bay is not important only for the mass of water that we most often think about, but for the entire drainage area that contributes to the Bay's resources and biological diversity. The drainage area, or watershed, basin of the Chesapeake Bay is immense, stretching across a 64,000 square- mile area of Virginia, Maryland, Pennsylvania, Delaware, West Virginia, and New York. The watershed is bounded on the north by the headwaters of the Susquehanna River in south-central New York. The western boundary is the Appalachian Mountain chain crests cutting across Pennsylvania, West Virginia and Virginia. To the south, the watershed's boundaries are formed by the upper tributaries of the James and other rivers flowing into the lowermost reaches of the Bay.

The watershed or drainage basin of the Bay is comprised of a series of landforms termed physiographic provinces that have different origins, histories, physical characteristics and biological communities. In addition to the Bay, these provinces are the Coastal Plain, the Piedmont, and the Appalachian Highlands.

Humans have occupied the Chesapeake Bay's watershed for at least 12,000 years. During that time, the resources of the Bay and its watershed have supported human societies that have grown ever more complex over time. Some of these human activities have had a minimal impact on the environment while others have resulted in immense physical and environmental changes.

As a partner in the Chesapeake Bay Program, the National Park Service has worked with a team of individuals and organizations with an interest in the Bay to prepare a written synthesis of human activity in the core portion of the Chesapeake Bay watershed. The area encompassed by the study includes the southeastern half of the Chesapeake drainage. It is bordered on the west by the Blue Ridge Mountains in Virginia, the Catoctin Mountains in Maryland and Pennsylvania, Pennsylvania's Kittatiny Mountains on the northernmost border, and the height of land separating the Delaware and Susquehanna drainages as the eastern border.

We invite you to read the Introductory Text to the study in HTML or read a description of the complete study and download it in PDF format.