Ann Lake vs Knife Lake
Water quality, depth, fish species, and recreation comparison.
Ann Lake reads lower on nutrients and algae than Knife Lake. Both are in Kanabec County, Minnesota.
Ann Lake and Knife Lake are both in Minnesota — a same-state head-to-head where the comparison comes down to lake-specific differences in depth, watershed, and monitoring history rather than the broader state-level water-quality regime. These two sit close on their nutrient and algae readings, Ann Lake versus Knife 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.
Ann Lake
Very murky, less than 2 ft of visibility.
Knife Lake
Very murky, less than 2 ft of visibility.
Side-by-Side Metrics
| Metric | Ann Lake | Knife Lake |
|---|---|---|
| Water Clarity | 2 ft | 2 ft |
| Phosphorus | 73.5 µg/L Better | 161.5 µg/L |
| Chlorophyll-a (Algae) | 57 µg/L Better | 97.2 µg/L |
| Maximum Depth | 17 ft Better | 15 ft |
| Surface Area | 653 acres | 1,259 acres |
| Public Access | Yes | Yes |
| Fish Species | 13 | 19 Better |
| Trophic State | eutrophic | hypereutrophic |
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
Ann Lake and Knife Lake read the same on nutrients and algae overall. The tiebreakers come down to clarity (Ann Lake: 2 ft, Knife Lake: 2 ft) and what you want from the lake. Ann Lake has fewer fish species than Knife Lake.
Stays via Stay22
Where to stay near Ann Lake and Knife Lake
Compare cabins, hotels, and vacation rentals around Ann Lake and Knife 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 Ann Lake and Knife Lake
Prices for Oct 30–Nov 1, 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 Ann Lake and Knife Lake?
Get lake water-quality updates plus the best cabin & lodging deals near Ann Lake and Knife Lake — straight to your inbox. No spam, unsubscribe anytime.
Source: EPA National Aquatic Resource Surveys, 2026.