New Jersey had the fourth-best beach water quality in the nation last year, while New York ranked 24th out of coastal states, a new report from the Natural Resources Defense Council says.

The environmental group's annual water quality report found that Tropical Storm Irene took a toll on beachgoers last summer, forcing beaches to be closed or warnings issued at a rate nearly double that of the previous year because of pollution concerns.

The report, using government data, found that in New York and New Jersey, there were 1,972 days when beaches were closed or advisories issued to the public, compared to 1,065 in 2010.

In New Jersey, 3 percent of beach water samples violated national standards in 2011, ranking the state 4th out of 30 coastal states. New York violated standards 10 percent of the time, ranking it 24th.

"This time of year, New York and New Jersey beaches are flooded with visitors from near and far, but unfortunately they're often inundated with dangerous pollution that can make swimmers sick as well," said Lawrence Levine, a senior attorney with the group. "Last year — thanks in part to Irene and record rainfall — this mess led to a massive uptick in beach closings in the area."

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New Jersey had 131 closing and advisory days last year, a 20 percent increase from 109 days in 2010. The increase last year was the result of increased precautionary closings and advisories due to heavy rain. In Monmouth County, some of these were issued as a pre-emptive measure because of Tropical Storm Irene, which caused 25 closing days during the storm.

The most common reported cause of contamination in the state was storm water runoff (79 percent), followed by sewage spills or leaks (5 percent), while 17 percent of contamination came from unknown sources.

The county with the highest health standard violation rate was Ocean County (5 percent), followed by Monmouth (4 percent). Atlantic and Cape May counties each had 1 percent violation rates.

The New Jersey beaches with the highest health standard violation rate were Beachwood Beach West in Ocean County (31 percent); the Highlands Recreation Center beach in Raritan Bay in Monmouth County (28 percent), the L Street Beach on the Shark River in Belmar in Monmouth County (20 percent), Windward Beach on Brick's Metedeconk River, and the Maxson Avenue beach on the Manasquan River in Point Pleasant (19 percent).

In New York State, there were 1,841 closing and advisory days last year at both coastal and Great Lakes beaches, a 93 percent increase from 956 days in 2010.

Some New York City beaches were also closed temporarily because of a nearly 200-million-gallon sewage spill in the Hudson River, after a treatment facility caught fire in July.

Niagara County had the highest health standard violation rate (31 percent), followed by Monroe (25 percent), Chautauqua (20 percent), Erie (16 percent), Queens (15 percent), Jefferson (14 percent), and Bronx and Westchester counties (11 percent each).

New York counties with the least violations of health standards were Cayuga and Wayne (both 0 percent) and Oswego (1 percent). Kings, Richmond and Suffolk counties each had a 7 percent violation rate, while Nassau had 8 percent.

The New York beaches with the most violations were Douglaston Homeowners Association in Queens County (42 percent), Krull Park in Niagara County (41 percent), Woodlawn Beach at Woodlawn Beach State Park in Erie County (32 percent) and Shore Acres Club in Westchester County (32 percent).

Statewide, there were 176 beaches with the lowest possible violation rate (0 percent), with the majority in Suffolk County (111 beaches), followed by Nassau (40 beaches), Queens (9 beaches), Oswego (5 beaches), Kings (4 beaches), Wayne (2 beaches), Westchester (2 beaches), Cayuga (1 beach), Erie (1 beach) and Niagara (1 beach).

Thirteen 13 beaches in New York City met health standards in 2011. This included four of six parts of Coney Island in Brooklyn, eight parts of Rockaway Beach in Queens, and one of two segments of Breezy Point (at Reid Avenue) in Queens.

In March, New York City and state announced a plan that will help tackle its 30 billion gallon-a-year sewage overflow problem. The plan will use porous pavement, green roofs, sidewalk tree boxes, and other increased green space to reduce the amount of rainfall that reaches the city's sewer system where it can trigger overflows when facilities are overloaded.

And last week the New York legislature passed the bill that requires publicly owned facilities to report sewage overflows to the public and to local and state agencies in a timely manner.