Beach · King County · WA
Is Three Tree Point safe to swim?
No advisory or algae bloom reported for this water today.
Updated July 19, 2026 · Washington beach program (EPA BEACON)
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What's in the water at Three Tree Point right now
As of July 19, 2026, Three Tree Point in King County, Washington 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 0.1 in, which can wash bacteria and nutrients into the water.
Blue-green algae at Three Tree Point
Three Tree Point is a lake in King County, Washington. 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 Three Tree Point
- Is it safe to swim in Three Tree Point right now?
- Three Tree Point 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 Three Tree Point have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at Three Tree Point. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in Three Tree Point?
- No bloom is detected at Three Tree Point 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 Washington lakes and beaches have swim advisories today?
- Today, 18 Washington waters are under a swim advisory and 9 more warrant caution, out of 1348 monitored waters SwimZone tracks in the state.
- How is Three Tree Point'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 Three Tree Point, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.