Warning signs were posted Thursday at Little Corona Beach after a routine sample showed bacteria levels that exceed standard health levels, officials said.
Beachgoers were urged to avoid going in the water in a 500-foot stretch of the beach, according to the Orange County Health Care Agency.
The effected area is near a storm drain, but it's unclear whether urban run-off could have caused the elevated bacteria levels, said Larry Honeybourne, the agency's program manager.
The agency tests the water at Little Corona two or three times a week for bacteria that can indicate the presence of disease-causing bacteria, but does not test for viruses or certain bacteria specifically.
Higher testing levels don't necessarily mean harmful bacteria is in the water, but sometimes bacteria from plants or soil can wash into an area and create higher levels of indicator bacteria, Honeybourne said.
Warning signs are removed after one day of clear tests, and in this case, could come down as soon as Friday, he said.
— Lauren Williams