(WASHINGTON) -- With beach season well underway and the Fourth of July holiday weekend approaching, an environmental advocacy group is out Wednesday with its annual beach report, ranking the nation's cleanest and most contaminated shores.
Judging by water cleanliness and not by beauty, the Natural Resources Defense Council gives its "Superstar Beach" rating to two beaches in Delaware and to one in each Minnesota and New Hampshire.
Futhermore, the group finds that the dirtiest beaches are in California, primarily in Los Angeles County, with three making the NRDC's list of beaches with persistent contamination problems.
The NRDC's David Beckman says the number of beach closures and advisories on dirty beaches over the past year is the second-highest since the council has been tracking them, standing at over 24,000.
"The two big problems, when it comes to America's beaches, are pollution runoff in urban areas and from agriculture," says Beckman. "It contains bacteria and viruses that can make you sick if you come into contact with them. And you can also get the same bacteria and viruses from sewage spills."
Michelle Mehta with the NRDC says swimmers exposed to the contamination can suffer from "gastrointestinal problems, ear, nose and throat problems, and skin rashes."
Here are the four beaches ranked as "Superstar Beaches" by the NRDC:
-- Delaware: Rehoboth Beach-Rehoboth Avenue Beach
-- Delaware: Dewey Beach
-- Minnesota: Park Point Lafayette Community Club Beach
-- New Hampshire: Hampton Beach State Park
And here are the 10 beaches that have had persistent contamination problems:
-- California: Avalon Beach
-- California: Cabrillo Beach Station
-- California: Doheny State Beach
-- Florida: Keaton Beach
-- Illinois: North Point Marina North Beach
-- New Jersey: Beachwood Beach West
-- Ohio: Villa Angela State Park
-- Texas: Ropes Park
-- Wisconsin: Eichelman Beach
-- Wisconsin: South Shore Beach
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