Beach Water Quality Monitoring



Map for reference purposes only and may not reflect current beach water conditions. The County of San Luis Obispo does not assume liability for any damages caused by any errors or omissions in the data. The County of San Luis Obispo makes no warranty of any kind, express or implied, that these data are accurate and reliable, nor does the fact of distribution constitute such a warranty. Independent verification of all data should be obtained by any user thereof. Users assume responsibility to determine the appropriate use of these data.


Environmental Health Services takes ocean water samples at nineteen locations along the coast on a weekly basis. Samples are analyzed for three (3) types of indicator bacteria, which at sufficient concentrations indicate the potential presence of microbes that may cause human illness. A ratio of two (2) of the three (3) bacteria types are analyzed as well. The results are compared to standards established by the State. If any of the State standards are not met, a Health Advisory is issued. A Health Advisory warns bathers to avoid water contact activities due to the presence of elevated levels of bacteria. An advisory spans fifty (50) yards north and south of the area where the sample is collected. Beaches are posted with advisory signs and remain posted until sample results indicate that bacteria levels meet State standards.

A beach health advisory occurs when a sample fails to meet one or more of the state bacteriological standards due to the presence of elevated levels of bacteria. When this occurs, the San Luis Obispo Environmental Health Services Division advises that you should avoid contacting and ingesting the water until sample results indicate acceptable levels of bacteria.

A rain advisory occurs during significant rain events where elevated levels of bacteria are expected due to storm water runoff. During this time, the San Luis Obispo Environmental Health Services Division advises the public to avoid water contact for 72 hours following a significant rain event.

A beach closure occurs when a specific beach location is closed to all water contact activities due to a higher health risk associated with known hazardous waste spills, such as untreated sewage reaching recreational waters.
This website is updated when weekly sample results become available. This information is also available on our hotline (805) 788-3411.

Below are helpful links related to Beach Water Quality Testing: 



Beach Water Quality Lab Results 2021-2023
SurfSafeSLO Advisories for 2021-2023
Contact Us
SurfSafeSLO Brochure
Last 30 Days of Beach Water Quality Results