An "advisory" is a warning letting the public know of the relative water quality of a beach that is monitored by the Agency. These are essentially "swim at your own risk" advisories.
Technically, an "advisory" means that during that specific week's sampling, the bacteria concentration at that beach was above the accepted Guam Water Quality Standard for marine recreational beaches. Thus Guam EPA recommends the public avoid swimming or wading at that beach to minimize the risk of contracting swimming-related illnesses.
An advisory is released for sites where the enterococci concentration found in a single sample is greater than 104 colonies/100mL and/or where the geometric mean of the single sample and four previous weeks' results are greater than 35 colonies/100 mL.
If either or both standards are violated, Guam EPA issues advisories to the public against swimming in those waters. Guam EPA notifies all print, electronic and broadcast media, appropriate village mayors, the Guam Hotel and Restaurant Association, Department of Parks and Recreation, Department of Public Health and Social Services, the Department of Agriculture's Division of Aquatic and Wildlife Resources, appropriate hotels, as well as dive shops and all interested parties upon request.
