Skip to main content
LakeQuality

Beltrami Lake reads lower on nutrients and algae than Three Island Lake. Both are in Beltrami County, Minnesota.

Reviewed by LakeQuality Editorial Team · Updated

Both Beltrami Lake and Three Island Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any differences in the readings here are about the lakes themselves, not the agencies sampling them. These two sit close on their nutrient and algae readings, Beltrami Lake versus Three Island Lake. The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.

With readings this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.

Beltrami Lake

Beltrami County, Minnesota

Good clarity, visible to about 11.2 ft.

Three Island Lake

Beltrami County, Minnesota

Good clarity, visible to about 11.8 ft.

Side-by-Side Metrics

MetricBeltrami LakeThree Island Lake
Water Clarity11.2 ft11.8 ft Better
Phosphorus15 µg/L Better17 µg/L
Chlorophyll-a (Algae)4.3 µg/L4.1 µg/L Better
Maximum Depth50 ft Better25 ft
Surface Area726 acres729 acres
Public AccessYesYes
Fish Species1617 Better
Trophic Statemesotrophicmesotrophic

A green ✓ marks the better value for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better). Surface area and trophic state carry no tick — a bigger lake is not a better lake.

Verdict

Beltrami Lake and Three Island Lake read the same on nutrients and algae overall. The tiebreakers come down to clarity (Beltrami Lake: 11.2 ft, Three Island Lake: 11.8 ft) and what you want from the lake. Beltrami Lake has fewer fish species than Three Island Lake.

Stays via Stay22

Where to stay near Beltrami Lake and Three Island Lake

Compare cabins, hotels, and vacation rentals around Beltrami Lake and Three Island Lake. Both lakes are pinned on the map, so you can see which stays sit nearer the one you pick. Switch to Satellite to see how close each is to the water.

Top-rated places to stay near Beltrami Lake and Three Island Lake

Prices for Nov 6–8, 4 adults. Change dates on the map below.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Planning a trip to Beltrami Lake and Three Island Lake?

Get lake water-quality updates plus the best cabin & lodging deals near Beltrami Lake and Three Island Lake — straight to your inbox. No spam, unsubscribe anytime.

Source: EPA National Aquatic Resource Surveys, 2026.