HAMPTON -- Hampton Beach is one of four "superstar beaches" in the country after being named for the fourth consecutive year as one of the safest beaches in the United States to swim because of the cleanliness of its water.

The Natural Resources Defense Council awarded New Hampshire's most popular beach Wednesday, June 29, with a 5-star rating in its annual report, "Testing the Waters: A Guide to Water Quality at Vacation Beaches."

"As a longtime resident and beach business owner, I have always known the beach was superstar quality," said Chuck Rage, chairman of the Hampton Beach Precinct Commission. "The good news is that now everyone else will know that we have one of the best beaches in the country."

The Washington, D.C., based environmental group ranked the nation's top 200 beaches in five categories regarding water quality and safety.

Beaches that met or surpassed standards in a specific category, such as cleanliness or water monitoring and best practices for testing and public notification, were given a star.

Only 17 beaches across the country received the five-star rating, with two in New Hampshire.

Wallis Sands Beach in Rye also made the list.

New this year was the "superstar status;" meaning not only did Hampton Beach receive a 5-star rating this year, but it has had perfect test results for the past three years, indicating a history of very good water quality.

Hampton Beach was one of only four that received the honor nationwide.

State officials said an "unbelievable" team effort goes into making Hampton Beach one of the cleanest beaches, involving people from the state Department of Environmental Services — which conducts the water quality tests from May to September — to the state park employees who clean the beach every day of the summer.

"The high marks for New Hampshire's coastal beaches are testament to the collaborative efforts of DES, N.H. Parks and Recreation and the local communities that host the beaches," said state DES Commissioner Tom Burack. "It is not by accident that New Hampshire has excellent water quality and a high quality of life. It takes a combination of dedication, good public policy, and resources on the state and local levels to achieve these outstanding results."

"Hampton Beach State Park hosts hundreds of thousands visitors a year, we are proud to offer them a superstar beach," said Commissioner George Bald, Department of Resources and Economic Development.

Rage believes the title will be a good boost to tourism. "I always hear from people in Rhode Island and Massachusetts who live near beaches that they come here because the water is so much more clean," Rage said. "But not only do we have clean water, it's the experience and everything Hampton Beach has to offer."

While the council rewarded the cleanest, most popular areas, its report was not all good news for the nation's beaches.

This year's report found that water quality at America's beaches remained largely steady, with 8 percent of beach water samples nationwide violating health standards in 2010, compared to 7 percent for the previous four years.

Nationwide, the vast majority of closing and advisory days, 70 percent, were issued because testing revealed bacteria levels in the water that exceeded health standards, indicating the presence of human or animal waste. Consistent with past years, stormwater runoff was the primary source of known pollution, indicating the problem has not been sufficiently addressed at the national level. Sewage overflows were also a contributor.

NRDC also highlighted the top 10 "Repeat Offender" beaches with persistently poor water quality year after year.

Beaches making that list include Keaton Beach in Florida and Cabrillo Beach Station in Los Angeles.

The report also highlighted closures, advisories and notices issued at beaches impacted by last summer's BP oil disaster. From the beginning of the spill until June 15, 2011, there have been a total of 9,474 days of oil-related beach notices, advisories and closures at Gulf Coast beaches due to the spill.