Beach · San Francisco County · CA
Is Aquatic Park - BAY#211_SL 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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What's in the water at Aquatic Park - BAY#211_SL right now
As of July 19, 2026, Aquatic Park - BAY#211_SL in San Francisco 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 Aquatic Park - BAY#211_SL
Aquatic Park - BAY#211_SL is a lake in San Francisco 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 Aquatic Park - BAY#211_SL
- Is it safe to swim in Aquatic Park - BAY#211_SL right now?
- Aquatic Park - BAY#211_SL 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 Aquatic Park - BAY#211_SL have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at Aquatic Park - BAY#211_SL. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in Aquatic Park - BAY#211_SL?
- No bloom is detected at Aquatic Park - BAY#211_SL 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 Aquatic Park - BAY#211_SL'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 Aquatic Park - BAY#211_SL, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.