Bay Facts
The Bay is full of interesting facts and trivia related to its history, wildlife, geography and more.
What is a watershed?
A watershed is an area of land that drains into a particular river, lake, bay or other body of water.
Learn moreThe Chesapeake Bay's first inhabitants
The first inhabitants of the Chesapeake Bay region are referred to as Paleo-Indians. They came more than 10,000 years ago from other parts of North America, drawn in by the abundance of wildlife and waterways.
Learn more35.5 million years
The formation of the Chesapeake Bay happened 35.5 million years ago when a meteor collided with Earth, forming a massive crater.
80% of the Bay's freshwater
Collectively, the Chesapeake’s three largest rivers—the Susquehanna, Potomac and James Rivers—provide more than 80% of the fresh water to the Bay.
12 miles wide
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.
What is brackish water?
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.
84 degrees Fahrenheit
Water temperatures in the Bay fluctuate widely throughout the year, reaching as high as 84 degrees in summer.
284,000 acres of tidal wetlands
Approximately 284,000 acres of tidal wetlands grow the Chesapeake Bay region. Wetlands provide critical habitat for fish, birds, crabs and many other species.
Learn more12 species of shark
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.
18.5 million people
The Chesapeake Bay watershed is home to more than 18 and a half million people. Ten million of them live along or near the Bay’s shores. About 150,000 new people move into the Bay watershed each year.
Learn more4,480 square miles of surface area
The surface area of the Bay and its tidal tributaries is approximately 4,480 square miles.
Largest land-to-water ratio in the world
The Chesapeake Bay’s land-to-water ratio is 14:1: the largest of any coastal water body in the world. This is why our actions on land have such a big impact on the Bay’s health.
The Powhatan tribes
There were many different tribes in the region before Europeans arrived, but the dominant group were Algonquian speakers known collectively as the Powhatan tribes.
The Bay's largest tributary
The Susquehanna River is the Bay’s largest tributary, and contributes about half of the Bay’s freshwater (about 19 million gallons per minute).
174 feet deep
The deepest part of the Bay, located southeast of Annapolis near Bloody Point, is called “The Hole” and is 174 feet deep.
51 billion gallons
Approximately 51 billion gallons of water flow into the Bay each day from its freshwater tributaries.
Learn moreWhat is a shallop?
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.
11,684 miles of shoreline
The Bay and its tidal tributaries have 11,684 miles of shoreline—more than the entire U.S. west coast.
1,800 local governments
There are nearly 1,800 local governments in the Bay watershed, including towns, cities, counties and townships.
34 degrees Fahrenheit
Water temperatures in the Bay fluctuate widely throughout the year, dropping as low as 34 degrees in winter.
10 U.S. presidents
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.
500 million pounds of seafood
The Bay produces about 500 million pounds of seafood per year.
Bald eagle recovery in the Chesapeake
In the 1970’s, there were as few as 60 breeding pairs of bald eagles in the entire Bay region. Today, as much as 3,000 breeding pairs of bald eagles can be found.
Learn more21 feet deep
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.