A water advisory was issued Thursday for the Silver Strand area of Coronado and Imperial Beach after E. coli was found in the drinking water system, according to the California Water Resources Board.

The presence of E. coli bacteria could mean the water is contaminated with human or animal waste, according to the San Diego County's Department of Environmental Health and Quality.

Residents impacted by the advisory should boil water for at least three minutes and let it cool before using it, county officials said. People are encouraged to use bottled water for drinking, brushing their teeth and food preparation until further notice.