David Knowles Writer
AOL News Surge Desk
(Sept. 6) -- The nation's waterways are fast becoming a wasteland.
Released Friday, a joint report by the Environmental Protection Agency, the U.S. Department of Agriculture, the U.S. Geological Survey and the Virginia Institute of Marine Science finds that the number of so-called "dead zones" in U.S. waters is 30 times more expansive today than it was in 1960.
The rise of hypoxia -- a lethal drop in oxygen levels in water to the point at which fish and plant life can no longer survive -- is largely attributable to man-made activity such as pollution and fertilizer runoff into the nation's waterways, but it is also found to be occurring because of climate change, the report concludes.
Oregon State University / AP
Francis Chan of Oregon State University drops a device to measure how much oxygen is in the water of the Pacific Ocean off Newport, Ore., on July 27, 2006.
Perhaps most alarming, hypoxia is now a serious problem along all of the nation's coasts as well as in the Great Lakes, the report said, impacting biodiversity and resulting in huge economic losses for the country's fishing industry.
"The nation's coastal waters are vital to our quality of life, our culture, and the economy," said Nancy H. Sutley, chair of the Council on Environmental Quality, one of the agencies that contributed to the report. "Therefore, it is imperative that we move forward to better understand and prevent hypoxic events, which threaten all our coasts."
Hypoxia occurs when oxygen levels dip below 2 to 3 milligrams per liter of water. At such levels, only bacteria can survive for prolonged periods of time. Fish species such as striped bass, American shad and yellow perch, however, all require at least 5 milligrams per liter of water in order to live.
Where the 'Dead Zones' Are the Worst
In the United States, the northern Gulf of Mexico remains the worst area for hypoxia. In large part, that's because of the massive agricultural runoff that is carried into the gulf by the Mississippi River. Nitrogen and phosphorous, used to help boost crop yields in fertilizer, have long been responsible for declining gulf oxygen levels. Globally speaking, only the Baltic Sea has a larger "dead zone" than the area off the coast of Louisiana and Texas.
NOAA
A small dead crab lies in hypoxic sediments off the coast of Louisiana in this photo provided by NOAA's Oceanic and Atmospheric Research, National Undersea Research Program and the Louisiana University Marine Consortium.
In the mid-1980s, the northern Gulf of Mexico hypoxic area was measured at an area of approximately 2,500 square miles. In 2008, the report found, its size had grown to 12,719 miles. Moreover, the report measured oxygen levels before the BP oil spill, which did nothing to improve conditions for the area's sea life.
But the report finds that the fastest growing "dead zones" in the U.S. are not located in the gulf.
"The area off the Oregon and Washington coast is now the second largest seasonal hypoxic zone in the United States and third largest in the world," according to a press release accompanying the report, "with serious repercussions for natural ecosystems and protected resources, including commercial fisheries. The report also finds that the Pacific and North Atlantic coasts have experienced the largest increase in hypoxic sites since the 1980s."
Long Island Sound Success Story
Not all of the news in the report was bad, however. In 1985, following sharp declines in water quality and a growing problem with hypoxia, The Long Island Sound Study issued new guidelines that called for stricter nitrogen controls. Twenty years later, after nitrogen loads had been cut by 20 percent, hypoxia began to be reversed.
"If properly planned and executed, adaptive management of nutrient inputs will lead to significant reductions in hypoxia," the report concluded. "However, if current practices are continued, the expansion of hypoxia in coastal waters will continue and increase in severity, leading to further impacts on marine habitats, living resources, economies, and coastal communities."
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