Flash Lake
Lake County, Minnesota83 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Flash Lake. Here is what has been measured.
- Impaired · Mercury
- 24 ft max depth
- Limited data
Flash Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 9 ft visibility. Maximum depth: 24 ft. Surface area: 82.77 acres.
Minnesota DNR's Standard Survey on June 17, 2024 caught 11.00 walleye per gill net at Flash Lake. Length samples in the latest survey that recorded them ran 7–20 inches. DNR survey details →
Flash Lake is a 83-acre lake in Lake County, Minnesota with a maximum depth of 24 feet. Overall water quality is improving over recent sampling years. The lake supports 5 documented fish species including green sunfish, northern pike, and walleye. No public access — the lake is private or restricted.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2020-07-24. Methodology: how these readings are compared.
Flash Lake covers about 83 acres in Lake County. For a place on the water, look through cabin and lake-house rentals near Flash Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Flash Lake is good for
From access and monitoring records, not editorial picks.
- Fishing5 species recorded
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Flash Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Flash 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 Flash Lake
These are the measurements Minnesota PCA publishes for Flash 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 9 ft. TSI 45.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 9ft | 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. | 45 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Flash Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on June 17, 2024 caught 11.00 walleye per gill net at Flash Lake. Length samples in the latest survey that recorded them ran 7–20 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Flash Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
7 surveys on file from MN DNR Fisheries. Most recent: 2024-06-17 (Standard Survey).
7 surveys on file · most recent 2024-06-17 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Walleye | 19.41 | 7–20 in 2024-06-17 | 1.42 lb |
| Yellow Perch | 17.73 | 5–8 in 2024-06-17 | 0.11 lb |
| Northern Pike | 7.11 | 18–25 in 2024-06-17 | 2.3 lb |
| White Sucker | 0.67 | 19 in 2024-06-17 | 2.81 lb |
| Green Sunfish | 0.33 | 4 in 2024-06-17 | 0.06 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.
Walleye
Yellow Perch
Northern Pike
White Sucker
From the 2024-06-17 survey
Flash is an 83-acre lake located 18 miles northeast of Ely in the Superior National Forest. It is comparable to Erickson, Hatchet, and Oriniak lakes in the Tower area. The lake is clear, moderately productive, and has a maximum depth of 24 feet. The surrounding forest is regenerating from a severe windstorm and…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Flash Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — FlashFisheries Lake Survey · MN DNR LakeFinder
Lake Details
Max depth
24 ft
Surface area
83 acres
Shoreline
3 mi
Littoral zone
71%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
0 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,463 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Flash Lake
Compare lakeside cabins, hotels, and vacation rentals near Flash 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 Flash 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 →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Flash Lake
Water Quality Trend: Improving
Based on 5 years of monitoring (2020–2025).
Water clarity
Improving5 years
EPA Impairment Status
Flash Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN38-0630-00 · Official waterbody report
Nearby Lakes in Lake County
Frequently asked questions about Flash Lake
Where is Flash Lake?
- Flash 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 Flash Lake?
- Flash Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 9 ft visibility. Maximum depth: 24 ft. Surface area: 82.77 acres.
Is Flash Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Flash Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Flash Lake?
- Flash Lake has a maximum depth of 24 feet. The lake covers 82.77 acres.
What fish are in Flash Lake?
- Fish species found in Flash Lake include green sunfish, northern pike, walleye, white sucker, yellow perch. Flash Lake is located in Lake County, Minnesota.
What did the DNR fisheries survey find at Flash Lake?
- Minnesota DNR's Standard Survey on June 17, 2024 caught 11.00 walleye per gill net at Flash Lake. Length samples in the latest survey that recorded them ran 7–20 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Flash Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Can I fish at Flash Lake?
- Public access to Flash 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 Flash Lake across LakeQuality
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Where this data comes from
4 measurements from 2 monitoring stations, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA4 samples · 2020
Analytical methods
- Field measurement/observation, generic method
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
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder