Beach Posting and Closures- Advisories

In California there are four types of warnings about beach water conditions: postings, closures, rain advisories, and permanent postings. Postings are the most common type of warning. Postings are triggered when a water sample fails to meet the DHS’ Ocean Water-Contact Sports Standard (California Health and Safety Code Sections 115875-115915). A beach posting is a warning to the public that the bacteria levels in the beach water may cause illness, and local health officers are recommending to the public to stay out of the water in areas where the signs are visible. The most common cause of postings is the dry weather discharge of urban runoff from storm drain systems.

A beach closure is a notice to the public that there has been a sewage discharge that is affecting the beach area. Closures are put in place immediately after a sewage spill is reported that may affect the beach. The closed beach area will be reopened when water samples meet standards. Because closures represent a definite health risk and postings indicate a potential risk, they are tracked separately.

Rain advisories are pre-emptive warnings that people should avoid swimming in ocean waters during a rain event and for three days after rainfall ceases. Rainwater often carries large amounts of bacteria from a variety of sources to the ocean. Rain advisories are issued via county hotlines, newspapers, and radio.

Permanent postings are sites where urban runoff discharges to the beach even during the dry season, and historic data shows that the beach water near the discharge point generally contains elevated bacteria levels.

The Water Board displays the closure and posting data submitted from the County Health Officers on its web site monthly. The Water Board also compiles the information into an annual report. These reports, available on the Water Board’s web site at https://www.waterboards.ca.gov/water_issues/programs/beaches/beach_surveys/, provide additional data on sources of pollution, testing methods, and causes of beach posting and closures.