The Chesapeake Bay is the largest estuary in the United States and third largest in the world. Once sculpted by ice, water, and powerful geologic forces over tens of millions of years, today's Bay is shaped by human forces as well.
During the past half century, the watershed (image below) has become a landscape full of fast-spreading cities, suburbs, and farms. That development has clouded the water and reduced the productivity of the habitat. Scientists have been monitoring the Bay closely since the 1980s, and the news has often been troubling—waterways polluted with nitrogen and phosphorous, algae blooms, dead zones, and fish kills.
But glimmers of hope have begun to emerge, and efforts to clean up the Bay are starting to make a difference. The gains so far are small, and only careful monitoring will help scientists sort out which aspects of the cleanup are proving effective and which are not.
The series of stories and images below describes the natural and unnatural problems in the Chesapeake watershed, which stretches from upstate New York to Newport News.
Click on each image for a deeper dive into one of the world's most famous and productive waterways.
A drop of water that falls in central New York takes a long ride to the sea. It flows past some extraordinary natural features that help tell the story of how the Chesapeake Bay came to be. Read more...
While farms remains a major source of Bay pollution, signs of improvements are beginning to emerge. Read more...
While the amount of wastewater pollution is declining, the spread of asphalt, pavement, and other impervious surfaces is increasing stormwater pollution. Read more...
Ships, airplanes, and satellites all play a role in monitoring Chesapeake water quality. Read more...
Two hundred years ago, a battle in the port city of Baltimore inspired the writing of America's national anthem.
Poplar Island is rising back out of the Chesapeake...with a little help.
Sea-level rise and invasive rodents have jeopardized the health of the marsh on Maryland's Eastern Shore.
Among the oldest mountains in the world, the Appalachian chain is now relatively low but visually striking.
An ancient collision between continents left a series of fractures in the bedrock around Virginia's Massanutten Mountains. The event spawned some unusual zig-zagging stretches on the Shenandoah River.
Resembling a work of art, the mountains of central Pennsylvania illustrates both the yearly cycle of change and the slow shaping of a landscape over millions of years.
