All beaches in Manhattan Beach - and throughout L.A. County - are under a "water quality advisory" following Tuesday's heavy rains.

The water quality advisory means that beach users should avoid water contact for at least 72 hours. The advisory is in effect until at least 7:30 a.m. on Friday, December 17. 

During and after rainstorms, bacteria levels can increase significantly as contaminants within the runoff enters the ocean. Bacteria levels may remain elevated up to 3 days depending upon the intensity of the rain and the volume of runoff. 

 A water quality advisory is issued when there is significant rainfall that can cause bacteria levels in ocean waters to increase. Elevated bacteria levels in ocean water may cause illness, especially in children and the elderly.

The Los Angeles County Department of Public Health recommends that beach users avoid contact with ocean water for a period of 3 days after significant rainfall, especially near flowing storm drains, creeks and rivers.

A full map of L.A. County Beaches under the water quality advisory can be seen here (via Google My Maps).

The water quality advisory (yellow conditions) is different from when a beach is closed (red conditions). A beach may be closed altogether, such as occurred in El Segundo earlier this year, when there is direct contamination from sewage.