Bay Facts

The widest point of the Chesapeake Bay measures 35 miles, and is located near the mouth of the Potomac River.

The 195-mile-long Rappahannock River is the longest free flowing river in the Chesapeake Bay watershed.

At filter feeders, oysters can filter up to 50 gallons of water a day.

The mouth of the Chesapeake Bay is about 12 miles wide between its northern point near Cape Charles, Virginia, and its southern point close to Cape Henry, Virginia.

The Susquehanna River is the Bay’s largest tributary, and contributes about half of the Bay’s freshwater (about 19 million gallons per minute).

Mallows Bay is the final resting place for more than 200 historic shipwrecks dating back to the Revolutionary War. Commonly referred to as the “Ghost Fleet” of Mallows Bay, it is the largest collection of shipwrecks in the Western Hemisphere.

Most of the water in the Bay, including in the middle portion of the Bay and its tidal rivers, is brackish–a mixture of salty and fresh, with a salinity level of greater than 0.5 ppt but less than 25 ppt.

The Chesapeake Bay is home to 26 different species of submersed aquatic vegetation (SAV), including freshwater plants, estuarine plants, redhead grass, and marine species.

Major rivers emptying into the Bay include the James, York, Rappahannock, Potomac, Patuxent, Patapsco and Susquehanna from the west and the Pocomoke, Wicomico, Nanticoke, Choptank and Chester from the east.

The Bay is surprisingly shallow. Its average depth, including all tidal tributaries, is about 21 feet. A person who is six feet tall could wade through more than 700,000 acres of the Bay and never get his or her hat wet.

Two of the United States’ five major North Atlantic ports—Baltimore and Hampton Roads—are on the Bay.

The Susquehanna River watershed includes nearly 50 thousand miles of rivers, streams and creeks.

The Bay and its tidal tributaries have 11,684 miles of shoreline—more than the entire U.S. west coast.

The word Chesepiooc is an Algonquian word referring to a village "at a big river." In 2005, Algonquian historian Blair Rudes helped dispel the widely-held belief that the name meant “great shellfish bay.”

The Bay itself is about 200 miles long, stretching from Havre de Grace, Maryland, to Virginia Beach, Virginia.

Legislation proposed by Maryland’s Senator Chris Van Hollen and Representative John Sarbanes to incorporate the bay into the nation’s park system.

Collectively, the Chesapeake’s three largest rivers—the Susquehanna, Potomac and James Rivers—provide more than 80% of the fresh water to the Bay.