Bay Facts
The Bay is full of interesting facts and trivia related to its history, wildlife, geography and more.
Largest estuary in the United States
The Chesapeake Bay is an estuary: a body of water where fresh and salt water mix. It is the largest of more than 100 estuaries in the United States and third largest in the world.
Learn moreReducing runoff
Fourteen percent of watershed residents use rain barrels to collect rainwater from their downspouts and keep runoff out of rivers and streams. While water collected in rain barrels is not safe to drink, it can be used to water plants or wash cars.
Learn more100,000 smaller tributaries
The Chesapeake Bay watershed has 150 major rivers and streams, but contains more than 100,000 smaller tributaries.
The 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 moreLargest 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.
Getting oxygen underwater
Just like those on land, animals in the Chesapeake Bay need oxygen to survive. Oxygen is present underwater in dissolved form, and in order to thrive, animals like blue crabs need dissolved oxygen concentrations of three milligrams per liter.
Learn more18 trillion gallons
The Chesapeake Bay holds more than 18 trillion gallons of water.
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 moreCaptain John Smith visits the Bay
In 1608, Captain John Smith set off on the first of two voyages where he charted the land and waterways, and later drew an elaborate and remarkably accurate map of the Chesapeake Bay.
Learn moreRemnants of an ancient river
A few deep troughs run along much of the Bay’s length and are believed to be remnants of the ancient Susquehanna River.
Six states and the District of Columbia
The Chesapeake Bay watershed stretches approximately 524 miles from Cooperstown, New York, to Norfolk, Virginia. It includes parts of six states—Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia—and the entire District of Columbia.
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.
Meaning of "Chesepiooc"
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.”
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.
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.
More than 200 historic shipwrecks
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.
500,000 Canada geese
More than 500,000 Canada geese winter in and near the Bay.
Learn more80,000 acres of underwater grasses
Nearly 80,000 acres of underwater grasses grow in the shallows of the Chesapeake Bay and its tributaries. Young and molting blue crabs rely on underwater grass beds for protection from predators.
Learn more200 invasive species
There are as many as 200 invasive species present in the Chesapeake Bay watershed that are causing some serious issues in an already-stressed ecosystem. Some examples include blue catfish, snakehead, zebra mussel, purple loosestrife, and nutria.
29 species of waterfowl
The Chesapeake region is home to at least 29 species of waterfowl.
Learn more60% of Chesapeake forests
Sixty percent of Chesapeake forests have been divided into disconnected fragments by roads, homes and other gaps that are too wide or dangerous for wildlife to cross.
Learn moreLongest free flowing river in the Bay watershed
The 195-mile-long Rappahannock River is the longest free flowing river in the Chesapeake Bay watershed.
21 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.
64,000 square miles
The area of the watershed is about 64,000 square miles.