San Diego County Department of Environmental Health and Quality (DEHQ) released a general rain advisory on Sunday, warning of increased bacteria levels in the coastline due to urban runoff from recent rainfall.
Swimmers, surfers, and other ocean users are warned that levels of bacteria can rise significantly in ocean waters, especially near storm drains, creeks, rivers, and lagoon outlets that discharge urban runoff. According to the DEHQ, activities such as swimming, surfing, and diving should be avoided for 72 hours following rain.
“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."
The warning applies to beaches from San Onofre State Beach south to Border Field, including Mission Bay and San Diego Bay. The DEHQ warns that while many coastal outlets are posted with permanent metal warning signs, additional temporary signs are not posted for General Advisories.
The department anticipates lifting the advisory by March 23 at 6 a.m., though it is subject to change. Closure signs will remain in place until ocean water sampling results meet state health standards.