Potomac tops conservation group's list of endangered rivers

The Potomac River is much healthier today than it was 40 years ago, when its chemical-laced, sewage-laden waters helped inspire the 1972 Clean Water Act. But the Washington waterway still has a long way to go, as suggested by its No. 1 ranking in a new list of America's most endangered rivers.

The list, released annually by conservation group American Rivers, doesn't necessarily name the country's 10 most polluted rivers. As American Rivers explains on its website, it selects the most at-risk rivers each year based on three criteria:

-A major decision in the coming year that the public can help influence.

-The significance of the river to human and natural communities.

-The magnitude of threats to the river and associated communities.

The significance of the Potomac is hard to miss: It's nicknamed "the nation's river" because it flows through the U.S. capital, and it supplies drinking water to 5 million people in four states and the District of Columbia. It has been on American Rivers' list before, but made the top spot in 2012 to highlighting efforts in Congress that could weaken the Clean Water Act. Because that law helped save the Potomac from rampant pollution in the past century - and because the Potomac has national symbolic value - American Rivers says it's "emblematic of what's at stake for rivers nationwide."

"When members of Congress fill a glass of water or drink their morning coffee, that water comes from the Potomac River," American Rivers president Bob Irvin said in a news release. "It's time to draw clear connections between healthy rivers, drinking water and public health in Washington, D.C., and in communities nationwide."

American Rivers isn't the only one pointing out the Potomac's problems. In its annual report card on the Chesapeake Bay ecosystem, the University of Maryland gave the river a "D" the past two years, down from a "C" in 2009. The 2011 report cited "declines in water clarity and benthic community" for the low grade. While the Potomac was threatened in the past by raw sewage and industrial dumping, it faces subtler threats today, such as toxic runoff from farms, cities and mines.

"Thanks to the Clean Water Act, you no longer see and smell most of the problems in the watershed, and no president is currently calling the Potomac a 'national disgrace,'" Ed Merrifield, president of Potomac Riverkeeper, said in a prepared statement. "But the hidden problems are many and in some ways worse than when the problems were palpable. ... The urban, suburban and agricultural stormwater runoff causes serious problems throughout the watershed, at times impairing the use of the river. The past fish kills and pervasive intersex fish issues due to the 'chemical soup' the fish swim in have made national headlines for years."

For the other nine rivers on the list, threats include new dams and reservoirs, dredging plans, coal mining and natural gas development.

---

America's Most Endangered Rivers, according to American Rivers; the states in which they flow; and the threats they face:

- Potomac River (Maryland, Virginia, Pennsylvania, West Virginia, District of Columbia): pollution

- Green River (Wyoming, Utah, Colorado): water withdrawals

Chattahoochee River (Georgia): new dams and reservoirs

Missouri River (Iowa, Kansas, Missouri, Montana, Nebraska, North Dakota, South Dakota, Wyoming): outdated flood management

Hoback River (Wyoming): natural gas development

Grand River (Ohio): natural gas development

South Fork Skykomish River (Washington): new dam

Crystal River (Colorado): dams and water diversions

Coal River (West Virginia): mountaintop removal coal mining

Kansas River (Kansas): sand and gravel dredging