Take the Plunge? Swim season begins Memorial Day weekend, but is it safe to go in? Of the country's 35 beach states and territories, only 11 -- including Maryland and Virginia -- have met updated Environmental Protection Agency (EPA) standards for testing the waters for illness-causing pollution. Many others still rely on tests that, according to the EPA, measure the wrong bacterium, fecal coliform. Despite its name, fecal coliform won't likely make you sick. Bigger threats, says the EPA, are E. coli and enterococci bacteria. Virginia began weekly testing last Wednesday, in time to get first results before the holiday weekend. Now the challenge is posting them. Read on.

Red flag Swimming in dirty water can cause acute gastrointestinal distress -- vomiting and diarrhea -- that is often "self-limiting and short-lived," said Michele Monti, who oversees water quality monitoring for the Virginia Department of Health. Children, seniors and those with weakened immune systems are at greatest risk. According to the EPA Web site, it's wise to avoid areas with visible sources of pollution such as discharge pipes and to choose areas with good circulation, such as beaches adjacent to open ocean waters.

Shore Watch The EPA requires that states make water quality info available to the public. Monti hopes the Web site www.vdh.state.va.us/whc will begin carrying Virginia water quality and beach closing updates before Memorial Day. The Maryland Department of the Environment aims to launch a similar site by midsummer, said a spokesman there. The EPA is in the process of putting together a Web site for updates of all monitored beaches, agency staff said.

For more information Environmental Protection Agency: www.epa.gov/beaches. Virginia Department of Health: www.vdh.state.va.us. Maryland Department of the Environment: www.mde.state.md.us.

-- Matt McMillen