Data Sources
Every figure on this site comes from a public source. Attribution is not just polite — it is required by the open-data licenses (ODbL 1.0 and CC-BY 4.0) that make the underlying datasets free to use. All source links below open in a new tab.
California Safe-to-Swim
License: ODbL 1.0
How it's used: Primary bacteria sampling data — enterococcus, E. coli, and fecal coliform counts from state and county monitoring agencies. Feeds the bacteria-based risk signal on every beach page.
Missing sources?
A few things are worth calling out so you know what is and is not in the risk signal:
- EBRPD freshwater lakes are seeded manually from the park district's advisory pages. An automated scraper is planned for a future phase.
- NOAA / NDBC water temperature is shown on the map dashboard for convenience, but is not currently an input to the safe / caution / unsafe score.
- Blue-green algae advisories are not yet integrated. When an agency posts an HAB advisory, check its official page directly before swimming.