Beach · Tinian County · MP
Is LEPROSARIUM BEACH II safe to swim?
Recent heavy rain may have spiked bacteria since the last clear sample.
Updated July 19, 2026 · Northern Mariana Islands beach program (EPA BEACON)
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Know before you get in at LEPROSARIUM BEACH II.
Get an alert the day a bacteria or algae advisory goes up.
What's in the water at LEPROSARIUM BEACH II right now
As of July 19, 2026, LEPROSARIUM BEACH II in Tinian County, Northern Mariana Islands 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 1.6 in, which can wash bacteria and nutrients into the water.
Blue-green algae at LEPROSARIUM BEACH II
LEPROSARIUM BEACH II is a lake in Tinian County, Northern Mariana Islands. 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 LEPROSARIUM BEACH II
- Is it safe to swim in LEPROSARIUM BEACH II right now?
- LEPROSARIUM BEACH II 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 LEPROSARIUM BEACH II have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at LEPROSARIUM BEACH II. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in LEPROSARIUM BEACH II?
- No bloom is detected at LEPROSARIUM BEACH II 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 Northern Mariana Islands lakes and beaches have swim advisories today?
- Today, 0 Northern Mariana Islands waters are under a swim advisory and 87 more warrant caution, out of 87 monitored waters SwimZone tracks in the state.
- How is LEPROSARIUM BEACH II'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 LEPROSARIUM BEACH II, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.