How to Use the Safe to Swim Map

The Safe to Swim map provides water quality data for popular swimming spots in California. Data is organized by sites, each representing a specific location where monitoring for fecal indicator bacteria, such as enterococci and E. coli, has been conducted. Sites are color-coded based on their safety status, which is determined by comparing recent monitoring results to the Statewide Bacteria Water Quality Objectives. Selecting a site will display its current status and historical data.

The full dataset for the Safe to Swim Map is typically updated on weekdays, depending on staff availability. The dataset is publicly available for download on the California Open Data Portal.

Exploring the map

Sites are shown as circles on the map, with colors indicating their current safety status (see the map legend for details). Click on a site marker to view detailed information about that location.

Finding a site on the map

To find a site, pan and zoom the map to your area of interest. Click any site marker to view its details. The selected site will be highlighted with a popup. You can also expand the map to full screen (note: your browser must be in full-screen mode to enlarge the map).

Use the search menu to find a site by entering its name or code. The list will filter as you type. Selecting a site from the menu will automatically pan the map to the location and highlight it. You can also use arrow keys to navigate between sites in the list.

Viewing site details

When you click on a site, a popup will appear on the map showing the site’s name and code. Additional details will appear on the right side of the screen, including the site’s current status, a description of that status, and the date of the most recent sample.

Understanding the data used

This dashboard displays bacteria concentrations measured from water samples taken at each site. To obtain a safety status for a site, the results are compared to the Statewide Bacteria Water Quality Objectives. Results that exceed the bacteria objectives indicate an elevated risk of illness. The method used to determine status uses two versions of the data: single samples from the last 30 days, and the rolling geometric mean (of the single samples) from the last six weeks. Both versions of the data are shown in the Data panel.

Disclaimer

This map is intended for informational purposes only and should not be used as the sole basis for making decisions about water contact activities. Always follow local advisories and guidelines. The data can change at any time and should not be used for any particular purpose other than general reference.

In addition, the statuses provided are approximations of how the Statewide Bacteria Water Quality Objectives are applied; we do not recommend using these statuses directly for regulatory or legal purposes. Assessments of water quality for regulatory purposes should be conducted on a case-by-case basis from the original data by up-to-date standards, which is available for download on BeachWatch and the California Environmental Data Exchange Network (CEDEN).