SAN DIEGO -- Urban runoff from rainfall prompted the San Diego County Department of Environmental Health to issue a general advisory Monday for coastal beaches from Oceanside south to Point Loma.

Swimmers, surfers and other ocean and bay users were warned to stay out of the water for 72 hours following rain as runoff can make the levels of bacteria rise significantly.

"Urban runoff may contain large amounts of bacteria from a variety of sources such as animal waste, soils and decomposing vegetation," according to a DEH statement.

The general advisory applies to coastal beaches from Oceanside south to Point Loma, including Mission Bay.