Swimmers, surfers and other beach water users were warned Sunday to avoid going into the water at all San Diego County beaches and bays because recent rainfall could bring urban runoff, which can cause bacteria levels to rise significantly.
"Urban runoff may contain large amounts of bacteria from a variety of sources such as animal waste, soil, and decomposing vegetation," the San Diego County Department of Environmental Health and Quality said. "Bacteria levels can remain elevated after a rainstorm depending upon the intensity of the storm, volume of runoff and ocean conditions."
"Water contact such as swimming, surfing and diving should be avoided during rain and for 72 hours following the rain event," said Nolberto Colon-Droz of the DEHQ.
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A beach closure was expected to remain in place for the Tijuana Slough shorelines because of sewage-contaminated flows from the Tijuana River entering the United States, Colon-Droz said.
The water contact closure area includes all beaches from the International Border to the south end of Seacoast Drive. Beach closure signs will remain in place until ocean water sampling results meet state health standards.