If rivers in the Chesapeake Bay watershed were healthy, they could help remove excess nutrients, which is considered a key component of restoring the bay  to health.  However, many of the bay’s rivers are not healthy and are themselves in need of restoration.

Dr. Margaret A. Palmer and J. David Allan, in an article published in the Winter 2006 journal of the National Academy of Science, defined river restoration as the repairing of waterways that can no longer perform their essential ecological and social functions, including:

1)   mitigating floods

2)   providing clean drinking water

3)   removing excess nutrients

4)   supporting fisheries and wildlife

Two additional benefits of  healthy streams are that they can increase property values and serve as a hub for recreation, Palmer and Allen said.

Their article, titled “Restoring Rivers,” reported that  more than one-third of river in the United States were impaired or polluted, including those running into the Chesapeake.  In 2005, scientists determined that the “dead zones”  covering nearly one-third of the Chesapeake Bay were a result of excess levels of nutrients and sediments from its rivers, Palmer and Allan reported.

How did the Chesapeake’s streams and rivers get so polluted? What happened to damage them so badly that they lost their ability to perform the essential ecological functions defined by Palmer and Allan?

Palmer and Allan provided multiple historical reasons. Below are a few:

1)   Population growth – people like to live and work near water, causing many industrial plants and cities to grow around them.

2)   Historically, the nation’s waterways have been a dumping ground for waste and raw sewage.

3)   Removal of trees and wetlands to make way for buildings and transportation.

4)   The building of dams.

5)   Paving of streams.