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The Chesapeake Bay Watershed:
Still Cloudy, With a Chance of Clearing

Text by Adam Voiland and Mike Carlowicz.
Visuals by Joshua Stevens, Jesse Allen, and Mike Taylor.
December 1, 2016

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.

Cloudless mosaic of the Chesapeake Bay Watershed

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.

Four-Part Feature Series

Click on each image for a deeper dive into one of the world's most famous and productive waterways.

Following a Raindrop from New York to Newport News

Following a Raindrop from New York to Newport News

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...

How Farms Affect the Chesapeake Bay’s Water

How Farms Affect the Chesapeake Bay’s Water

While farms remains a major source of Bay pollution, signs of improvements are beginning to emerge. Read more...

How Cities and Suburbs Affect Chesapeake Bay

How Cities and Suburbs Affect Chesapeake Bay

While the amount of wastewater pollution is declining, the spread of asphalt, pavement, and other impervious surfaces is increasing stormwater pollution. Read more...

Studying Chesapeake Bay from Above

Studying Chesapeake Bay from Above

Ships, airplanes, and satellites all play a role in monitoring Chesapeake water quality. Read more...

Other Images of the Chesapeake Watershed

Star-Spangled City

Star-Spangled City

Two hundred years ago, a battle in the port city of Baltimore inspired the writing of America's national anthem.

A Disappearing Island Restored

A Disappearing Island Restored

Poplar Island is rising back out of the Chesapeake...with a little help.

Blackwater National Wildlife Refuge

Blackwater National Wildlife Refuge

Sea-level rise and invasive rodents have jeopardized the health of the marsh on Maryland's Eastern Shore.

Appalachian Mountains

Appalachian Mountains

Among the oldest mountains in the world, the Appalachian chain is now relatively low but visually striking.

The Sinuous Shenandoah

The Sinuous Shenandoah

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.

Fall Colors in Pennsylvania

Fall Colors in Pennsylvania

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.