Beach · Marquette County · MI
Is North of Picnic Rocks safe to swim?
Recent heavy rain may have spiked bacteria since the last clear sample.
Updated July 19, 2026 · Michigan beach program (EPA BEACON)
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What's in the water at North of Picnic Rocks right now
As of July 19, 2026, North of Picnic Rocks in Marquette County, Michigan 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 1.5 in, which can wash bacteria and nutrients into the water.
Blue-green algae at North of Picnic Rocks
North of Picnic Rocks is a lake in Marquette County, Michigan. 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 North of Picnic Rocks
- Is it safe to swim in North of Picnic Rocks right now?
- North of Picnic Rocks 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 North of Picnic Rocks have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at North of Picnic Rocks. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in North of Picnic Rocks?
- No bloom is detected at North of Picnic Rocks 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 Michigan lakes and beaches have swim advisories today?
- Today, 47 Michigan waters are under a swim advisory and 120 more warrant caution, out of 882 monitored waters SwimZone tracks in the state.
- How is North of Picnic Rocks'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 North of Picnic Rocks, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.