Bay Facts

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

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.

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

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.

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

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.

The 195-mile-long Rappahannock River is the longest free flowing river in the Chesapeake Bay 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).

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

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

The Susquehanna River watershed includes nearly 50 thousand miles of rivers, streams and creeks.

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.

At filter feeders, oysters can filter up to 50 gallons of water a day.

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

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.

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