Lake · MN
Is Gunflint Lake safe to swim?
No advisory or algae bloom reported for this water today.
Updated August 20, 2026 · EPA CyAN satellite
No bacteria advisory or sampling for this water.
No blue-green algae bloom detected in the latest clear satellite image. This is a satellite estimate, not a safety guarantee, and does not replace an official advisory.
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Gunflint Lake is clear today. Be the first to know when it's not.
SwimZone checks this water every day and pings you the moment a bacteria or algae advisory goes up.
What's in the water at Gunflint Lake right now
As of August 20, 2026, Gunflint Lake in Minnesota has no advisory posted. EPA's CyAN satellite detected no blue-green algae bloom in the latest clear image (August 19, 2026), which is an estimate, not a guarantee. Modeled rainfall over the past week was about 0.1 in (Open-Meteo, a gridded estimate that can differ from a local gauge), which can wash bacteria and nutrients into the water.
Blue-green algae at Gunflint Lake
Gunflint Lake is a lake in Minnesota. EPA's CyAN satellite detected no blue-green algae bloom in the latest clear image (August 19, 2026), which is an estimate, not a guarantee.
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.
Bloom history at Gunflint Lake
From EPA CyAN's satellite archive
Each bar is that summer's peak EPA CyAN satellite estimate (log scale); the red cap is the part above the bloom-level threshold. Satellite estimates, not water samples or posted advisories.
Over 7 summers of EPA CyAN satellite imagery since 2020, Gunflint Lake has not shown a satellite-estimated bloom-level signal. This is an estimate, not a guarantee, and conditions can change quickly, so check the current read and official advisories before you swim.
When to swim at Gunflint Lake
It is currently peak season for blue-green algae, when warm, calm water lets blooms form fastest. This water has no recorded advisory-level bloom in its satellite history, which makes it a comparatively steady summer swim spot; conditions still change between samples, so check the current read before you go.
Frequently asked: swimming in Gunflint Lake
- Is it safe to swim in Gunflint Lake right now?
- Gunflint Lake has no advisory posted today. EPA's CyAN satellite detected no blue-green algae bloom in the latest clear image (August 19, 2026), which is an estimate, not a guarantee. Conditions can change quickly with wind, heat, and rain, so check the posted signs and look at the water before you get in.
- Does Gunflint Lake have blue-green algae (cyanobacteria)?
- EPA's CyAN satellite detected no blue-green algae bloom at Gunflint Lake in the latest clear image (August 19, 2026). This is a satellite estimate below the sensor's detection limit, not a guarantee: cyanobacteria can appear within hours in warm, calm, nutrient-rich water, so look before you swim.
- Can dogs swim in Gunflint Lake?
- No bloom is detected at Gunflint Lake 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 often does Gunflint Lake have blue-green algae blooms?
- Over 7 summers of EPA CyAN satellite imagery since 2020, Gunflint Lake has not shown a satellite-estimated bloom-level signal. This is an estimate, not a guarantee, and conditions can change quickly, so check the current read and official advisories before you swim.
- How many Minnesota lakes and beaches are unsafe for swimming today?
- Today, 0 Minnesota waters are above a safe-contact threshold and 451 more warrant caution, out of 1178 monitored waters SwimZone tracks in the state.
- How is Gunflint Lake'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 Gunflint Lake, and a recent-rainfall overlay, all refreshed daily. It was last updated August 20, 2026.
Before you swim: the basics
Swim spots near Gunflint Lake
All Minnesota →All 6 monitored waters nearest Gunflint Lake are clear today.
| Water | Distance | Today | Algae read | Sampled |
|---|---|---|---|---|
| Loon LakeLake · Cook County | 1.4 mi | No advisory | None detected | Aug 19 |
| North LakeLake | 5.7 mi | No advisory | None detected | Aug 19 |
| South LakeLake · Cook County | 6.8 mi | No advisory | None detected | Aug 19 |
| Frost LakeLake · Cook County | 9.2 mi | No advisory | None detected | Jul 21 |
| Tuscarora LakeLake · Cook County | 9.5 mi | No advisory | None detected | Aug 19 |
| Moss LakeLake · Cook County | 10 mi | No advisory | None detected | Jul 21 |