MONTEREY (CBS SF) – An advisory warning residents to stay out of the water at Monterey Municipal Beach has been expanded to all county beaches for at least the next three days, Monterey County health officials announced Thursday.

On Wednesday, the health department issued an advisory for Monterey Municipal Beach because of high amounts of bacteria found in ocean water samples taken there on Monday.

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The advisory was expanded today as rainy weather descended on the area. Rainfall is associated with increased bacterial levels in ocean water because of runoff, particularly in the area of man-made and natural storm drains such as culverts, streams and rivers, according to the county.

Bacteria, viruses, protozoa and chemicals may contaminate storm drain water and contact with the storm drain water may cause illness, county health officials said.

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County officials advise the public not to swim or have contact with ocean water for three days after the last rain event, according to county health officials.

For more information about this advisory, residents can visit www.mtyhd.org/beach.

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