The nation's cleanest beachwaters are along the upper half of the Atlantic seaboard, in Virginia, Delaware and New Hampshire, a national environmental group said Wednesday.
At the other end of the spectrum, Louisiana has the most contaminated waters, followed by Ohio, Indiana and Illinois, the Natural Resources Defense Council said in a new report.
The study used federal clean-water standards to assess coastal and lake beaches in 30 states, based on samples taken in 2008, the most recent year for which data are available.
"Pollution from dirty stormwater runoff and sewage overflows continues to make its way to our beaches," said Nancy Stoner, a water analyst with the environmental group. "From contracting the flu or pink eye, to jeopardizing millions of jobs and billions of dollars that rely on clean coasts, there are serious costs to inaction."
California and Florida, two large states with some of the country's most well-known beaches, fare quite differently in the report.
Florida is tied with New Jersey at ninth among the 30 states, with 3 percent of their beachwater samples exceeding bacterial levels set by the Environmental Protection Agency.
California, by contrast, is at No. 19, tied with South Carolina, Alabama and New York. Their beachwater samples were found to be contaminated 8 percent of the time.
Farther north along the Pacific Coast, Washington state tied with Connecticut at No. 11 with 4 percent of their beachwater samples failing to meet the federal standards.
On the Atlantic, just 1 percent of samples from a total of 87 beaches in Virginia, Delaware and New Hampshire were contaminated, making their waters the most pristine.
Almost as clean were the waters off North Carolina, Georgia and Maryland, with 2 percent of samples from 356 beaches testing contaminated.
Hawaii's fabled waters fared just as well, with 2 percent of samples from 444 beaches failing to meet the standards.
Lake and river waters in Arkansas ranked as the cleanest among inland states -- just 2 percent of samples from 18 beaches were found to be polluted.
Among other states in the report, Texas is tied at No. 15 with a 6 percent pollution rate, Pennsylvania is 23rd at 9 percent, Mississippi ties at No. 24 with a 14 percent contamination rate, and Illinois is 26th at 15 percent.
Though Florida fares reasonably well overall in the study, it has 10 beaches on the list of those where the share of contaminated water samples was 25 percent or higher.
The state's dirtiest beach is at Shired Island in Dixie County -- with 90 percent of 29 samples taken in 2008 exceeding federal norms.
California, the most populous state and home to nearly 650 public beaches, placed 20 on the most-contaminated list.
The Golden State's most-polluted waters are at Avalon Beach on Catalina Island, across from Long Beach and south of Los Angeles; 62 percent of 42 samples taken there failed to meet the national standards.
However, none of the popular beaches between San Francisco and Los Angeles -- including beaches in Monterey Bay, Morro Bay or Santa Barbara -- were included in the report.
The full NRDC report: www.nrdc.org/water/oceans/ttw/ttw2009.pdf
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