Island Lake
Carlton County, Minnesota320 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Island Lake. Here is what has been measured.
- Eutrophic
- 22 ft max depth
- Public access
Island Lake in Carlton County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.1 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 14.7 µg/L. Maximum depth: 22 ft. Surface area: 319.99 acres.
Minnesota DNR's Targeted Survey on July 8, 2024 caught 1.67 northern pike per trap net at Island Lake. DNR survey details →
Island Lake is a 320-acre productive, nutrient-rich eutrophic lake in Carlton County, Minnesota with a maximum depth of 22 feet (9-foot average). Overall water quality is improving over recent sampling years. The lake supports 14 documented fish species including black bullhead, black crappie, and bluegill. Public access is available. Compared to the 21 other monitored lakes in Carlton County, Island Lake ranks #16 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-30. Methodology: how these readings are compared.
What Island Lake is good for
From access and monitoring records, not editorial picks.
- Fishing14 species recorded
- Ice seasonIce-out around Apr 17
Swimming conditions
Readings onlyElevated nutrients
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Island 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 Island Lake
These are the measurements Minnesota PCA publishes for Island Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5.1 ft. Phosphorus 26 µg/L. Chlorophyll-a 14.7 µg/L. TSI 54.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 26µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 14.7µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 54 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Island Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Targeted Survey on July 8, 2024 caught 1.67 northern pike per trap net at Island Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Island Lake’s water-quality measurements separately, and the water-quality trend over 3 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
9 surveys on file from MN DNR Fisheries. Most recent: 2024-07-08 (Targeted Survey).
9 surveys on file · most recent 2024-07-08 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 21.34 | 3–8 in 2024-07-08 | 0.25 lb |
| Largemouth Bass | 7.86 | 5–16 in 2023-07-24 | 1.06 lb |
| Golden Shiner | 6.95 | ||
| Yellow Bullhead | 4.97 | 8–12 in 2024-07-08 | 0.77 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.
Bluegill
Largemouth Bass
Yellow Bullhead
From the 2024-07-08 survey
A targeted survey of nearshore fish species in Lower (South) Island Lake was conducted on July 8th, 2024 by Index of Biological Integrity (IBI) Program Staff. Sampling sites were evenly spaced around the lake and each was sampled by backpack electrofishing and seining with a 50-foot, where possible. Backpack…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Island Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — Lower (South) IslandFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Lower (South) Island (0249)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — Lower (South) IslandFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — Lower (South) IslandPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
22 ft
Average depth
9 ft
Surface area
320 acres
Shoreline
5.1 mi
Littoral zone
65%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
14 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,293 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Island Lake
Compare lakeside cabins, hotels, and vacation rentals near Island Lake in Carlton 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Island Lake are listed below.
Top-rated places to stay near Island Lake
Prices for Oct 9–11, 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 whole trip? See where to stay at Minnesota’s top lakes →
Follow Island Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Island Lake
Water quality readings over time
3 seasons of samples on record (2021–2025). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Stable3 years
Phosphorus
Improving-26.5 µg/L/yr2 years
Chlorophyll-a
Improving-15.5 µg/L/yr2 years
Ice season
Typical ice-out
Apr 17
Earliest Apr 11, 2015 · Latest May 4, 2022
Typical ice-in
Nov 14
Earliest Nov 2, 2003 · Latest Nov 19, 2006
Most recent ice-out
May 4
2022
10 observations · Minnesota PCA ice records
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Island Lake under Clean Water Act (NPDES) discharge permits. 2 facilities have a reported Clean Water Act violation in the past three years.
- Cromwell WwtpCromwell · 0.9 mi away · NPDES MN0051101Recent violation
- Premier Horticulture Inc - Black Lake And Wright Bogs - Plant SiteCromwell · 1.9 mi away · NPDES MN0055115Recent violation
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Nearby Lakes in Carlton County
Frequently asked questions about Island Lake
Where is Island Lake?
- Island Lake is a lake in Carlton County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Island Lake?
- Island Lake in Carlton County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.1 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 14.7 µg/L. Maximum depth: 22 ft. Surface area: 319.99 acres.
Is Island Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Island Lake?
- Island Lake has a maximum depth of 22 feet and an average depth of 9 feet. The lake covers 319.99 acres.
What fish are in Island Lake?
- Fish species found in Island Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, walleye, white sucker, yellow bullhead, yellow perch. Island Lake is located in Carlton County, Minnesota.
What did the DNR fisheries survey find at Island Lake?
- Minnesota DNR's Targeted Survey on July 8, 2024 caught 1.67 northern pike per trap net at Island Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Island Lake’s water-quality measurements separately, and the water-quality trend over 3 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
When does Island Lake thaw?
- Island Lake typically has ice-out around Apr 17. Ice typically forms around Nov 14. The open water season is approximately 211 days.
Can I fish at Island Lake?
- Public access to Island Lake is listed as yes on the lake record. 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 Island Lake across LakeQuality
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Where this data comes from
86 measurements from 2 monitoring stations, 2021–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA86 samples · 2021–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (2)
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate