Bay Facts

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

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

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

The Chesapeake Bay watershed contains three distinct geologic regions: the Atlantic coastal plain, the Piedmont plateau and the Appalachian province.

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

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.

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

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

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

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.

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

There are nearly 1,800 local governments in the Bay watershed, including towns, cities, counties and townships.

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.