One Lake
One Lake in Lake County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 7.5 ft visibility. Maximum depth: 57 ft. Surface area: 845.95 acres.
- Clarity
- 7.5 ft
- Max depth
- 57 ft
- Area
- 846 acres
- Trend
- → Stable
- Public access
- Yes
Next lake in Lake County
Why One Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For One Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
One Lake is a 846-acre lake in Lake County, Minnesota with a maximum depth of 57 feet. The lake supports 7 documented fish species including bluegill, cisco species, and lake whitefish. Public access is available.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-03. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for One Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Moderate clarity, visible to about 7.5 ft. Trophic State Index: 48.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 7.5 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 48 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near One Lake
Compare lakeside cabins, hotels, and vacation rentals near One 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 One Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 57 ft |
| Surface Area | 846 acres |
| Shoreline Length | 31.6 mi |
| Littoral Zone | 53% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fish Species
Click a species to see every graded lake where it is documented.
Fishing One Lake
DNR Fisheries Survey Summary
5 surveys on file from MN DNR Fisheries. Most recent: 2025-08-01 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| CIS | 3.67 | 0.17 lb |
| Bluegill | 3.61 | 0.38 lb |
| White Sucker | 3.40 | 1.9 lb |
| Northern Pike | 2.92 | 2.06 lb |
| Tullibee (Cisco) | 2.12 | 0.14 lb |
| Walleye | 1.31 | 0.81 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
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.
CIS
Bluegill
White Sucker
Northern Pike
From the 2025-08-01 survey
Temperature and dissolved oxygen (DO) measurements were collected on August 1st, 2025, in two locations in Lake One, WQ1 and WQ2, 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, also…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for One Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — OneFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — One (1896)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — OnePublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: → Stable
Based on 4 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.024 m/yr | 4 |
EPA Impairment Status
One Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN38-0605-00 · Official waterbody report
Nearby Lakes in Lake County
Frequently asked questions about One Lake
What is the water quality grade for One Lake?
- One Lake in Lake County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 7.5 ft visibility. Maximum depth: 57 ft. Surface area: 845.95 acres.
Is One Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. One Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is One Lake?
- One Lake has a maximum depth of 57 feet. The lake covers 845.95 acres.
What fish are in One Lake?
- Fish species found in One Lake include bluegill, cisco species, lake whitefish, northern pike, rock bass, walleye, white sucker. One Lake is located in Lake County, Minnesota.
Explore One Lake across LakeGrade
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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)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated 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