As the dog days of August settle in, Californians again head to the beach to cool off and dive into the surf. However, water monitoring along the Golden State’s shores shows that beach goers may at times risk illness by taking the plunge.

In 2001, California had 6,568 beach closings and advisories, up from 5,780 during 2000, according to a report by the Natural Resources Defense Council released late last month. The increase, however, does not mean that water contamination is getting worse, just that as public health officials monitor water more often they are finding contamination that once went undetected, the report concluded.

Beach goers may feel safer as a result, but some say that is a false sense of security.

Even though water samples are now drawn on a weekly or even daily basis at many of the state’s most popular beaches, it takes up to 48 hours to get the results, according to Linda O’Connell, scientist with the California Water Resources Control Board.

When contamination is detected, health officials will close a beach. In the interim, however, swimmers can be exposed to waterborne pathogens that cause infections of the intestines, urinary tract, eyes, and upper respiratory tract, among other diseases.

Moreover, in an ironic twist created by the technological limits of water monitoring, by the time officials close a beach, the contamination may have ended. A study by two marine scientists – Molly K. Leecaster and Stephen B. Weisberg – shows that some 70% of water contamination incidents clear within 24 hours.

“Right now, we’re telling people it was unsafe to swim yesterday and we don’t really know what it is today,” said Weisberg.

Hopefully the time gap between taking water samples and finding out if a beach is contaminated will close over the next year under a .5 million state-funded project.

The water board has contracted with the Southern California Coastal Water Resources Center in Westminster, Calif., to develop a “rapid” test method for detecting contamination at beaches. The goal is to be able to close beaches in less than 24 hours after taking a water sample, says O’Connell.

“No one has a rapid method that works on bacteria in California salt water at the levels of bacteria we need to find,” said Weisberg, who directs the coastal center and sits on a National Academy of Sciences committee on waterborne pathogens.

Weisberg said the goal is to find promising pathogen monitoring technologies now being used or developed for testing freshwater, drinking water, food, and bioterrorism incidents and tailor them for testing ocean water at California beaches.

Early this week, the center issued a request for proposals from companies and scientists who are developing test methods that might be applicable to beach monitoring. It will assess those technologies and pick the most promising to fund for further development.

In May, the center will hold a conference in Monterey on beach monitoring science and technology in conjunction with the Alliance for Coastal Technologies and the Monterey Bay Aquarium Research Institute. Weisberg said that the center hopes to have a rapid test method for beach contamination within 18 months.

There is little doubt the improved monitoring technology is the key to better protecting California beach goers.

"The reporting agencies don't know the source of pollution because, in many cases, no one is systematically tracking it down and attempting to do anything about it," said Sarah Chasis, senior attorney for NRDC and director of the organization's water and coastal program. "Identifying the source of the problem is a critical step to improving beach water quality. It's important not only to regularly monitor beaches and notify the public of contamination, but also to identify and control the pollution sources."

Weisberg said it would probably take about ten years to develop technology that will allow public health officials to instantly trace contamination back to it’s source. “What we really want is a Geiger counter where we can trace contamination upstream to the source of the problem. That’s the long-term goal.”

In the short run, according to Weisberg, the goal is to find a way to quickly detect and notify the public of contamination in the surf.