Insula Lake
Lake County, Minnesota2,840 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Insula Lake. Here is what has been measured.
- Impaired · Mercury
- 63 ft max depth
- Limited data
Insula Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7.5 ft visibility. Maximum depth: 63 ft. Surface area: 2840.04 acres.
Minnesota DNR's Standard Survey on July 9, 2001 caught 2.42 walleye per gill net at Insula Lake. Length samples in the latest survey that recorded them ran 7–29 inches. DNR survey details →
Insula Lake is a 2,840-acre lake in Lake County, Minnesota with a maximum depth of 63 feet. Overall water quality is improving over recent sampling years. Limited fish-species data available. No public access — the lake is private or restricted.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-02. Methodology: how these readings are compared.
Insula Lake covers about 2,800 acres in Lake County. If you are planning to stay, you can search lake houses and cabins around Insula Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Insula Lake is good for
From access and monitoring records, not editorial picks.
- Deep water63 ft surveyed max depth
- Big water2,840 acres
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Insula Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Insula Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Insula Lake
These are the measurements Minnesota PCA publishes for Insula Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 7.5 ft. TSI 48.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 48 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Insula Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on July 9, 2001 caught 2.42 walleye per gill net at Insula Lake. Length samples in the latest survey that recorded them ran 7–29 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Insula Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
3 surveys on file from MN DNR Fisheries. Most recent: 2025-08-05 (Targeted Survey).
3 surveys on file · most recent 2025-08-05 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| White Sucker | 5.04 | 6–21 in 2001-07-09 | 1.34 lb |
| Tullibee (Cisco) | 4.63 | 5–8 in 2001-07-09 | 0.15 lb |
| Walleye | 3.33 | 7–29 in 2001-07-09 | 1.02 lb |
| Northern Pike | 2.92 | 13–37 in 2001-07-09 | 3.08 lb |
| Yellow Perch | 1.03 | 5–8 in 2001-07-09 | 0.09 lb |
| Rock Bass | 0.47 | 5–7 in 2001-07-09 | 0.23 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
White Sucker
Tullibee (Cisco)
Walleye
Northern Pike
From the 2025-08-05 survey
Temperature and dissolved oxygen measurements were collected from the deepest basin in Insula Lake on August 5th, 2025. This was done to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Whitefish, the most sensitive coldwater species present in this lake (Cisco,…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Insula Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — InsulaFisheries Lake Survey · MN DNR LakeFinder
Lake Details
Max depth
63 ft
Surface area
2,840 acres
Shoreline
75 mi
Littoral zone
42%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
34 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,509 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Insula Lake
Compare lakeside cabins, hotels, and vacation rentals near Insula Lake in Lake County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Insula Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Follow Insula Lake’s readings
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Fishing Insula Lake
Water quality readings over time
2 seasons of samples on record (2020–2025). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Improving2 years
EPA Impairment Status
Insula Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption.
Source: EPA ATTAINS assessment unit MN38-0397-00 · Official waterbody report
Nearby Lakes in Lake County
Frequently asked questions about Insula Lake
Where is Insula Lake?
- Insula Lake is a lake in Lake County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Insula Lake?
- Insula Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7.5 ft visibility. Maximum depth: 63 ft. Surface area: 2840.04 acres.
Is Insula Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Insula Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
How deep is Insula Lake?
- Insula Lake has a maximum depth of 63 feet. The lake covers 2840.04 acres.
What did the DNR fisheries survey find at Insula Lake?
- Minnesota DNR's Standard Survey on July 9, 2001 caught 2.42 walleye per gill net at Insula Lake. Length samples in the latest survey that recorded them ran 7–29 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Insula Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Can I fish at Insula Lake?
- Public access to Insula Lake is listed as no on the lake record, so confirm before you make the trip. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Insula Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
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Fish species and best lakes in Lake County
Species activity outlook by water temperature and season
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Where this data comes from
6 measurements from 5 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA6 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (5)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder