Beach · San Luis Obispo County · CA
Is Oceano Dunes State Rec Area - OCB13 safe to swim?
No advisory or algae bloom reported for this water today.
Updated July 19, 2026 · California beach program (EPA BEACON)
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Know before you get in at Oceano Dunes State Rec Area - OCB13.
Get an alert the day a bacteria or algae advisory goes up.
What's in the water at Oceano Dunes State Rec Area - OCB13 right now
As of July 19, 2026, Oceano Dunes State Rec Area - OCB13 in San Luis Obispo County, California is clear to swim. Blue-green algae are not currently monitored at this water. No fecal-bacteria advisory is posted (state beach program). Rainfall over the past week totaled 0.0 in, which can wash bacteria and nutrients into the water.
Blue-green algae at Oceano Dunes State Rec Area - OCB13
Oceano Dunes State Rec Area - OCB13 is a lake in San Luis Obispo County, California. Blue-green algae are not currently monitored at this water.
Blue-green algae (cyanobacteria) blooms are most common from midsummer into early fall, when the water is warm, calm, and rich in nutrients from runoff. They can produce toxins that make people sick and can be rapidly fatal to dogs, so skip water that looks green, scummy, or like spilled paint, and keep children and pets out of it.
Frequently asked: swimming in Oceano Dunes State Rec Area - OCB13
- Is it safe to swim in Oceano Dunes State Rec Area - OCB13 right now?
- Oceano Dunes State Rec Area - OCB13 is clear to swim today. Blue-green algae are not currently monitored at this water. Conditions can change quickly with wind, heat, and rain, so check the posted signs and look at the water before you get in.
- Does Oceano Dunes State Rec Area - OCB13 have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at Oceano Dunes State Rec Area - OCB13. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in Oceano Dunes State Rec Area - OCB13?
- No bloom is detected at Oceano Dunes State Rec Area - OCB13 today, but dogs are much more vulnerable to blue-green algae than people, and blooms can form within hours. Always keep dogs away from water that looks green, scummy, or discolored, and rinse them off after swimming.
- How many California lakes and beaches have swim advisories today?
- Today, 28 California waters are under a swim advisory and 4 more warrant caution, out of 452 monitored waters SwimZone tracks in the state.
- How is Oceano Dunes State Rec Area - OCB13's water quality measured?
- SwimZone builds this read from EPA CyAN satellite imagery for blue-green algae, official beach and fecal-bacteria advisories where a program monitors Oceano Dunes State Rec Area - OCB13, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.