Bay Facts

The Bay receives about half its water volume from the Atlantic Ocean in the form of saltwater. The other half (freshwater) drains into the Bay from the enormous 64,000-square-mile watershed.

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

Captain John Smith and his men sailed the Chesapeake Bay in a modest wooden boat called a shallop–an open wooden workboat such as a barge, dory, or rowboat that was small enough to row but also had one or two sails.

Salinity is highest at the mouth of the Chesapeake Bay, where water from the Atlantic Ocean enters.

The Bay’s width ranges from four miles near Aberdeen, Maryland, to 30 miles near cape Charles, Virginia.

The deepest part of the Bay, located southeast of Annapolis near Bloody Point, is called “The Hole” and is 174 feet deep.

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

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.

In 1524, Italian Captain Giovanni da Verrazano became the first recorded European to enter the Chesapeake Bay.

There are twelve known species of shark that have been sighted in the Chesapeake Bay, with only five considered a common occurrence—smooth dogfish, sand tiger shark, sandbar shark, spiny dogfish, and bull shark.

The area of the watershed is about 64,000 square miles.

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

The surface area of the Bay and its tidal tributaries is approximately 4,480 square miles.

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

Healthy forests can capture more than 85% of the nitrogen that falls onto them from the air.

The Chesapeake Bay was formed about 10,000 years ago when glaciers melted and flooded the Susquehanna River valley.

There are nearly 1,800 local governments in the Bay watershed, including towns, cities, counties and townships.

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.

While one-third of watershed residents have volunteered their time or donated their money to a charitable organization, less than two in ten volunteers have done so for an environmental organization.