Beach · Lake County · MN
Is Knife River Marina Beach safe to swim?
No advisory or algae bloom reported for this water today.
Updated July 19, 2026 · Minnesota beach program (EPA BEACON)
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What's in the water at Knife River Marina Beach right now
As of July 19, 2026, Knife River Marina Beach in Lake County, Minnesota 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 Knife River Marina Beach
Knife River Marina Beach is a lake in Lake County, Minnesota. 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 Knife River Marina Beach
- Is it safe to swim in Knife River Marina Beach right now?
- Knife River Marina Beach 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 Knife River Marina Beach have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at Knife River Marina Beach. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in Knife River Marina Beach?
- No bloom is detected at Knife River Marina 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 Minnesota lakes and beaches have swim advisories today?
- Today, 307 Minnesota waters are under a swim advisory and 34 more warrant caution, out of 1162 monitored waters SwimZone tracks in the state.
- How is Knife River Marina 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 Knife River Marina Beach, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.