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Potomac Named Most Endangered River
The Potomac River is seen by hundreds of thousands each day as it flows under bridges and past memorials. It is used for recreational activities, and provides drinking water for five million people.
Before the Potomac reaches Washington, it runs through farmland in four states, and continues on to the Chesapeake Bay, the country's largest estuary1.
All along its course, pollution undermines the river's water quality, says American Rivers President Bob Irvin.
"It flows through farmland, where pesticides2 are running off from the fields, where farm waste is running into the streams," said Irvin. "Then as it makes its way down through the urban area of Washington, DC, we have runoff from our streets, and when it rains really hard we have raw sewage flowing into the river."
That runoff concerns Don Boesch, head of the University of Maryland Center for Environmental Science. He says it is creating dead zones where aquatic3 plants and marine4 life cannot survive.
"It's got low light penetration5 and sometimes lowest levels of oxygen in the water," Boesch noted6.
He says before the river can become healthier, the nutrient7 runoff must be controlled.
"These are good things that stimulate8 life in the river, but they are actually in excess, so they cause lots of negative problems in the river," Boesch added.
A nearby coal powered electrical plant will close soon, but until then, it is putting toxic9 substances into the water and changing the habitat, says Whit10 Overstreet, with the environmental group, Potomac Riverkeepers.
"They discharge hot water back into the river that wouldn't be there naturally, which can be problematic for aquatic life," Overstreet noted.
Scientists have also found that chemicals appear to be causing intersexed fish - especially male fish with female traits. But fishing guide Steve Chaconas says he thinks the Potomac has improved from the filthy11 river it was years ago.
"The fish are very vibrant," said Chaconas. "People are picking up after themselves, finally!"
American Rivers warns the Potomac and other rivers could backslide if the Clean Water Act of 1972 is weakened, a distinct possibility, says Irvin.
"Congressmen from various parts of the country, representing big agricultural interests and industry interests, are trying to weaken the act, trying to prohibit the federal government from protecting, for example, small headwater streams and wetlands, and from regulating the use of pesticides on farmland," Irvin explained.
Clean water advocacy groups are calling on Congress to kill any legislation that erodes12 those vital protections.
1 estuary | |
n.河口,江口 | |
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2 pesticides | |
n.杀虫剂( pesticide的名词复数 );除害药物 | |
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3 aquatic | |
adj.水生的,水栖的 | |
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4 marine | |
adj.海的;海生的;航海的;海事的;n.水兵 | |
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5 penetration | |
n.穿透,穿人,渗透 | |
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6 noted | |
adj.著名的,知名的 | |
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7 nutrient | |
adj.营养的,滋养的;n.营养物,营养品 | |
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8 stimulate | |
vt.刺激,使兴奋;激励,使…振奋 | |
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9 toxic | |
adj.有毒的,因中毒引起的 | |
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10 whit | |
n.一点,丝毫 | |
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11 filthy | |
adj.卑劣的;恶劣的,肮脏的 | |
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12 erodes | |
侵蚀,腐蚀( erode的第三人称单数 ); 逐渐毁坏,削弱,损害 | |
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