11,510 monitored waters · refreshed daily
Where the water is off-limits today
Swim safety is local and it moves with the weather. Right now 0 of the waters we track are under a full advisory and 3,000 under caution. Here are today's flagged waters, worst first, then browse every water by state.
Right now
Under an advisory today
A bacteria or blue-green algae advisory is in effect. This list reshuffles as new samples and satellite bloom reports come in.
No advisories posted across our monitored waters right now.
Right now
Use caution today
Conditions are borderline, from elevated blue-green algae, recent heavy rain, or a watch-level reading.
Showing the first 24 of 3,000. Open a state below for the rest.
Every water
Browse by state
Each state page lists all of its monitored lakes, ponds, and beaches with today's read, worst first.
Get an alert when your water goes off-limits
These are today's reads, and conditions move with the weather. SwimZone checks the monitored waters every day, and the app will ping you the morning yours goes under an advisory. One email when it launches.
Using this in a story?
Free to cite with attribution and a link to SwimZone. Every state has its own page (for example swimzone.app/ohio), and every water links to its live daily read from official EPA and state monitoring. Full methodology.
For a custom cut, your county, your lake, or an interview about the model, email hello@swimzone.app.