Bay Facts

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

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.

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.

There were many different tribes in the region before Europeans arrived, but the dominant group were Algonquian speakers known collectively as the Powhatan tribes.

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.

Forty-six percent of watershed residents never use toxic pesticides in or around their homes. You can evaluate a pesticide’s toxicity to judge the risk in using it, or make your own non-toxic pesticide with garlic, vinegar, cooking oil and other common household items.

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.

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

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

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.

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

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.