Bay Facts

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

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.

During the winter, the Bay supports 87 species of waterbirds. Of these wintering waterbirds, 14 species rely on the Bay to serve as habitat for more than 10% of their continental populations.

The Chesapeake Bay Program was organized in 1983 to help lead and direct restoration in the Chesapeake Bay.

Water temperatures in the Bay fluctuate widely throughout the year, dropping as low as 34 degrees in winter.

Water temperatures in the Bay fluctuate widely throughout the year, reaching as high as 84 degrees in summer.

Blue crabs have a rapid growth rate and short life span. Few blue crabs live longer than three years.

More than 1,800 vessels have met their end in Bay waters, lying broken and battered on the Bay's floor.

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

There have been 10 U.S. presidents from the Chesapeake Bay watershed, including George Washington, Thomas Jefferson, James Madison, James Monroe, William Henry Harrison, John Tyler, Zachary Taylor, Woodrow Wilson, James Buchanan and Joe Biden.

A few deep troughs run along much of the Bay’s length and are believed to be remnants of the ancient Susquehanna River.

The formation of the Chesapeake Bay happened 35.5 million years ago when a meteor collided with Earth, forming a massive crater.

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

The Chesapeake Bay watershed has 150 major rivers and streams, but contains more than 100,000 smaller tributaries.

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

There are 6,282,718 acres of accessible green space within the Chesapeake Bay watershed.

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 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.