America's cleanest (and dirtiest!) beaches

(CNN) -

Just when you thought it was safe to go into the water, the Natural Resources Defense Council has released its annual beach quality report and it's not pretty.

According to NRDC, a large number of U.S. seashores continue to suffer from storm water runoff and sewage pollution that can cause swimmers to become very ill.

The report, Testing the Waters: A Guide to Water Quality at Vacation Beaches, looks at 2011 data collected from test results taken at more than 3,000 beaches nationwide. It examines the pollution factors that affect these U.S. vacation spots and calls for public efforts to clean up.

The report found that last year the nation's beach waters continued to be affected by serious contamination and pollutants from human and animal waste. As a result, America's beaches had the third-highest number of closings or advisories in the report's history, with the second-highest number occurring just the year before. Progress, according to the report, is not being made.

"Our beaches are plagued by a sobering legacy of water pollution," said NRDC senior attorney Jon Devine. "Luckily, today more than ever, we know that much of this filth is preventable and we can turn the tide against water pollution. By establishing better beach water quality standards and putting untapped 21st century solutions in place -- we can make a day at the beach as carefree as it should be, and safeguard America's vital tourism economies."

The Environmental Protection Agency estimates that more than 10 trillion gallons of untreated storm water makes its way into surface waters each year, and hundreds of billions of gallons of wastewater - which includes sewage and storm water - are released in combined sewer overflows. This water dumps into many of America's coastal areas.

But the NRDC report is not all bleak. It includes a guide that rates the water quality and practices for testing water and administering public notifications at each beach. When a seashore exceeds the NRDC's expectations, it receives a 5-star rating.

Beaches that rated five stars with last year's data are:

-- California: Newport Beach in Orange County (2 of 3 monitored sections)

-- Newport Beach -- 38th Street

-- Newport Beach -- 52nd/53rd Street

-- California: Bolsa Chica Beach in Orange County

-- California: Huntington State Beach in Orange County

-- Alabama: Gulf Shores Public Beach in Baldwin County

-- Alabama: Gulf State Park Pavilion in Baldwin County

-- Delaware: Dewey Beach in Sussex County

-- Maryland: Ocean City at Beach 6 in Worcester County

-- Minnesota: Park Point Franklin Park / 13th Street South Beach Park Point in St. Louis County

-- Minnesota: Lafayette Community Club Beach in St. Louis County