ON the Fourth of July, the water temperature at the beach in Ocean City, N.J., was hovering around 60 degrees, but that didn’t stop people from going for a swim.
Neither did the large brown pipes that open all along the water’s edge, apparently also enjoying a sunny day off but ready to deliver storm water to the ocean at the next rain.
Steve Niedzielski, visiting from Downingtown, Pa., was building sand castles near the shoreline with his two young children, but said concerns about water quality were not on his mind. “In the past, I did think about it a lot because they had issues about people dumping their trash in the ocean,” he said. “But in recent years it hasn’t been a problem.”
Ocean dumping may not be a problem on the nation’s beaches the way it was in the late 1980s, but there is evidence that beachgoers are facing a different, less visible threat: contamination from storm water and in some cases sewage that ends up in the waters where people swim.
On Tuesday, the Natural Resources Defense Council released its 18th annual survey of beach water quality in the United States, reporting 22,571 closing and advisory days for possible contamination at 3,500 ocean, bay and Great Lakes beaches last year.
While the number of closings and advisories actually declined from 2006 — when 25,643 days at the beach were spoiled — the 2007 results were still the second-highest recorded since the council began tracking this data.
“Storm water is actually the largest cause of beach closings and advisories in the United States,” said Nancy Stoner, director of the council’s clean water project. “After a heavy rainfall, if the pipes are discharging on the beach, you could be swimming in all kinds of contaminants and pollutants that are not good for you in the long run.”
Ocean City was not singled out in the council’s report, and in fact it and the other beaches in Cape May County tend to be cleaner than those farther north in the state. But the council report cited New York and New Jersey as states that have experienced significant increases in beach closing and advisory days, up 33 percent in 2007 after a 96 percent increase in 2006.
Beach communities like those in New York and on the Jersey Shore face a constant struggle to balance urban infrastructure needs and the maintaining of clean recreation areas. Ocean City has employees who rake and clean up the beaches daily, said Jim Rutala, the city’s administrator, as well as many trash cans and recycling containers on the beach. But given that the community sits on a barrier island, storm water ends up in nearby waterways — as it does in many areas — along with whatever is picked up along the way.
A storm washes a potentially toxic mix of trash and chemicals into sewers — pet waste, bird droppings, motor oil, fertilizer, cigarette butts and other litter — which travels via pipes to rivers, lakes and the sea.
Some urban areas like New York City have combined sewerage systems that carry both raw sewage and storm water runoff to sewage treatment plants, which, during heavy rains, are designed to release that mix directly into waterways to avoid overflowing.
That means a less visible type of contamination than the trash that once washed up on the beach.
“You don’t necessarily see it,” Ms. Stoner said. “The water might be a little more cloudy, but a lot of times people don’t notice that.”
The decision on whether to close a beach or issue an advisory is primarily based on water quality tests by local health agencies, made once a week for most recreational beaches. The tests look for bacteria indicating human or animal waste, but not other contaminants.
Relying on data submitted by these health authorities to the United States Environmental Protection Agency, the council reported that 7 percent of all samples taken in 2007 failed national health standards, the same percentage as in 2006.
A crucial problem for weekend beachgoers is getting information on water quality in time to use it. Typically during the summer, bathers won’t know for days after testing is completed whether the water has harmful bacteria because the current testing method can take 24 hours to show results, and some areas require a second test before officials decide to post a warning or close a beach.
“Right now, it takes up to three days for beaches to be closed because of water quality, so when the tests come back, you know you shouldn’t have been swimming for the past three days,” said Cindy Zipf, executive director of Clean Ocean Action, a coalition working to protect coastal waters in New York and New Jersey. “It’s kind of an awkward public health message.”
Because heavy rains have consistently led to failed tests in some locations, health agencies sometimes issue pre-emptive beach advisories or closings after a downpour, without waiting for the next test.
New Jersey is one of the states participating in a pilot program to evaluate a rapid testing method that would provide results within several hours, one of the main goals of the E.P.A. and other environmental organizations.
“I would say in the next two to three years we’ll be in a position to see that rapid reliable testing is used much more frequently throughout the country,” said Benjamin H. Grumbles, the E.P.A.’s assistant administrator for water.
THERE is also a push to develop a newer testing standard, since the current one hasn’t been updated in 20 years, as well as for studies to determine how often beachgoers actually get sick from contaminated water.
“It’s not an exact science,” Mr. Grumbles said of monitoring the health effects of polluted beach water. But he cited gastrointestinal problems, rashes, and ear, nose and throat infections as some of the illnesses that can result.
Children, the elderly and people with compromised immune systems are particularly vulnerable, but advocacy groups worry about anyone who spends time in affected waterways.
In fact, the Surfrider Foundation, based in San Clemente, Calif., was founded in 1984 by a group of surfers concerned about getting sick from bacteria floating around their boards or lurking in the waves.
“We believe there is a problem — at least at some locations sometimes,” said Rick Wilson, coastal management coordinator for the Surfrider Foundation, though he acknowledged that progress had been made in the past decade.
“Prior to 2000, a lot of beaches weren’t tested at all,” he said. “It was a big step forward to get more standardized monitoring around the country.”
The 2000 Beach Act provides much of the funding for water quality testing programs nationwide and requires posting the results, which accounts for some of the rise in advisories and closings.
“We went from doing maybe 500 samples in 2002 to almost 5,000 in 2007,” said Robert Waters, who manages the beach monitoring program for the Suffolk County Department of Health Services in New York. “You can’t make the connection that because we have more advisories now that water quality is worse. It’s hard to tell.”
Ms. Stoner, however, said the data reported by the National Resources Defense Council in recent years were based on a relatively stable number of beaches being tested.
“It’s not due to increased testing in general over the past six years,” she said. “Instead it’s that there are more pollution problems at the beaches that are identified.”
Officials working on water quality issues cite aging sewerage systems as the main cause of beach water pollution, and note that testing the water is only the first step in solving the problem.
“The ultimate solution is not just to test the waters and tell people whether or not they’re going to get sick,” Ms. Stoner said, “but to clean them up.”
The Beach Protection Act, which was passed by the House of Representatives in April and is awaiting action in the Senate, would not only authorize more money for testing programs, particularly rapid testing methods; it would also expand the use of federal funds to include tracking and preventing the sources of water pollution.
Individual behavior also plays a role in cleaning up swimming waters — especially avoiding littering both upstream and at the beach.
“Street litter that comes out of storm drains is a big issue, and beach litter is a problem,” said Virginia Loftin, a research scientist with the New Jersey Department of Environmental Protection. “It’s human behavior that we would like to see changed.”
AFTER the Fourth of July fireworks ended in Ocean City, heavy rains washed the streets clean of revelers’ debris. But by the next morning, some of that litter had traveled through the sewerage system and into the ocean, and then washed up on the beach.
A quick count revealed 180 cigarette butts along the shoreline between two sewer outflow pipes, along with straws, toothpicks, a wine cork, a candy wrapper, a coffee stirrer, a wooden ice cream spoon, a foam cup and a plastic bottle cap — just a sampling of the trash marking the water line in the sand.
Nearby, a young man wearing white board shorts and a gray tank top finished his cigarette and dug a hole with his toes a few feet from the water, dropped in the butt and covered the hole again. That brought the tally to 181 cigarette butts along just a fraction of the shoreline that day, waiting to welcome swimmers to the beach.
Many states post information about beach water quality and closings online; some localities also have hot lines.
As a general rule, health officials suggest staying out of the water for 24 hours after a heavy rain or at least keeping your head above water if you swim, especially near urban areas.