Boil-water advisory

A boil-water advisory or boil-water order is a public health advisory or directive given by government or health authorities to consumers when a community's drinking water is, or could be, contaminated by pathogens.

Under a boil-water advisory (BWA), the Centers for Disease Control and Prevention recommends that water be brought to a rolling boil for one minute before it is consumed in order to kill protozoa, bacteria and viruses. At altitudes above 2,000 meters (6,561 feet), boiling should be extended to 3 minutes, as the lower boiling point at high altitudes requires more time to kill such organisms.