By Mark Lebetkin
The Active Times

You're in good company if Independence Day weekend means heading out to the beach for a little surf and sand, but you may want to check more than just the weather and UV forecast beforehand. Looking up the water quality report could save you from spending most of your beach trip in the bathroom -- or worse.

Harmful bacteria and viruses that cause rashes, gastrointestinal distress and hosts of other diseases are present at unsafe levels in the water at many of the nation’s beaches, according to a new report by the Natural Resources Defense Council.

The environmental non-profit just issued its annual beach scorecard, rating the water quality, testing standards and advisory systems at 200 of the country's most popular ocean and Great Lake beaches.

"There's no ominous theme song to warn swimmers of this risk like you might see in the movies,” said Steve Fleischli, director of the NRDC’s water program.

"This danger is silent and invisible," he added. "After a day playing in the water, the family may get dysentery, hepatitis, stomach flu, infections or rashes."

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The report also ranked states by the percentage of their water quality tests in 2012 that failed national standards for bacterial contamination.

At the bottom of the list: Minnesota, Wisconsin and -- dead last -- Ohio. The Great Lakes states were among the worst out of the 30 ranked, and only Michigan managed to rise to the middle of the pack.

But pollution from sewage spills and stormwater runoff isn't just a freshwater phenomenon. California ranked 20th, with eight percent of water samples statewide showing unsafe bacterial levels. Orange, Los Angeles and San Francisco Counties, among others, exceeded that average significantly, and one Channel Islands beach was the most contaminated out of more than 3,000 nationwide that the NRDC examined.

Although the EPA sets minimum standards for allowable bacterial levels, states are responsible for setting their own testing and beach closure guidelines, which vary widely from state to state -- even from beach to beach -- and are highly dependent on federal funds provided through the BEACH Act. The Obama administration has threatened to defund the program in next year’s budget.

But it's not all bad news for beachgoers. States like Delaware, New Hampshire and North Carolina all have aggressive monitoring programs and low contamination levels. The NRDC also named 13 "5-Star Beaches" where there is little to no pollution, and where officials will be quick to let you know if there is. They are:

Alabama: Gulf Shores Public Beach
Alabama: Gulf State Park Pavilion
California: Bolsa Chica Beach
California: Newport Beach, 38th Street, 52nd/53rd Street
California: San Clemente State Beach, Avenida Calafia, Las Palmeras
Delaware: Dewey Beach - Dagsworthy
Delaware: Rehoboth Beach - Rehoboth Ave.
Maryland: Ocean City at Beach 6
Michigan: Bay City State Recreation Area
Minnesota: Park Point Franklin Park / 13th Street South Beach
Minnesota: Lafayette Community Club Beach
New Hampshire: Hampton Beach State Park
New Hampshire: Wallis Sands Beach at Wallis Road

No matter where you live, though, the NRDC advises checking for advisories online, looking out for posted signs and nearby drainage pipes, and avoiding the water for 24 hours after it rains -- 72 hours for heavy rain.

For a complete slideshow of the America's Most Contaminated Beaches, go to The Active Times.

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-- Where to See Incredible Natural Phenomena
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-- 40 Great American Day Hikes to Do This Summer

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