Beach · Guam County · GU
Is United Seamen's Service Beach (USO Beach) safe to swim?
Recent heavy rain may have spiked bacteria since the last clear sample.
Updated July 19, 2026 · Guam beach program (EPA BEACON)
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Know before you get in at United Seamen's Service Beach (USO Beach).
Get an alert the day a bacteria or algae advisory goes up.
What's in the water at United Seamen's Service Beach (USO Beach) right now
As of July 19, 2026, United Seamen's Service Beach (USO Beach) in Guam County, Guam carries a swim caution. 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 1.1 in, which can wash bacteria and nutrients into the water.
Blue-green algae at United Seamen's Service Beach (USO Beach)
United Seamen's Service Beach (USO Beach) is a lake in Guam County, Guam. 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 United Seamen's Service Beach (USO Beach)
- Is it safe to swim in United Seamen's Service Beach (USO Beach) right now?
- United Seamen's Service Beach (USO Beach) carries a swim caution 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 United Seamen's Service Beach (USO Beach) have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at United Seamen's Service Beach (USO Beach). Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in United Seamen's Service Beach (USO Beach)?
- No bloom is detected at United Seamen's Service Beach (USO Beach) 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 Guam lakes and beaches have swim advisories today?
- Today, 0 Guam waters are under a swim advisory and 31 more warrant caution, out of 31 monitored waters SwimZone tracks in the state.
- How is United Seamen's Service Beach (USO Beach)'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 United Seamen's Service Beach (USO Beach), and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.