Bay Facts

Nine in ten watershed residents never toss food wrappers, cups or cigarette butts on the ground. Almost eight in ten watershed residents pick up litter when they see it.

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

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

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.

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.

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.

The 110-mile-long Patuxent River is the longest river to flow exclusively within the borders of Maryland.

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

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

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

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

Half of pet owners always pick up after their pet, but one-third of pet owners seldom or never do so. Pet waste contains bacteria that can harm human health and contaminate the water we use for drinking, swimming and fishing.

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.

Eighty-six percent of watershed residents believe if people work together, water pollution can be fixed.

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

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.

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