Cox Lake
Cox Lake in Clearwater County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 14 ft visibility. Maximum depth: 30 ft. Surface area: 60.99 acres.
- Clarity
- 14 ft
- Typical in August
- 73°F
- Max depth
- 30 ft
- Area
- 61 acres
- Trend
- ↓ Declining
- Public access
- Yes
Next lake in Clearwater County
Why Cox 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 Cox 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.
Cox Lake is a 61-acre lake in Clearwater County, Minnesota with a maximum depth of 30 feet (10-foot average). Overall water quality is declining over recent sampling years. The lake supports 9 documented fish species including black crappie, bluegill, and brown bullhead. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-08-19. 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 Cox Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 14 ft. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 14 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Cox Lake
Compare lakeside cabins, hotels, and vacation rentals near Cox Lake in Clearwater 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 Cox Lake
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Water Temperature
Cox Lake typically sits around 73°F at the surface in August. Summer average is about 69°F. Usually warmest in Aug (about 73°F) and coldest in Jun (about 65°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 40 field readings (2016–2024) via the EPA Water Quality Portal. See the full Cox Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 30 ft |
| Average Depth | 10 ft |
| Surface Area | 61 acres |
| Shoreline Length | 2.7 mi |
| Littoral Zone | 64% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Cox LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Cox Lake
DNR Fisheries Survey Summary
2 surveys on file from MN DNR Fisheries. Most recent: 2018-06-18 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Largemouth Bass | 50.72 | 0.84 lb |
| Bluegill | 36.12 | 0.08 lb |
| Northern Pike | 6.36 | 1.95 lb |
| Black Crappie | 5.00 | 0.24 lb |
| Pumpkinseed | 4.85 | 0.12 lb |
| Yellow Perch | 4.83 | 0.17 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.
Largemouth Bass
Bluegill
Northern Pike
Black Crappie
From the 2018-06-18 survey
Cox Lake is a 75-acre lake located west of Itasca State Park in southern Clearwater County. There is County-owned, unimproved public water access on the west shore of the lake off County Road 39 with parking for two trucks/trailers. The access may not be suitable for larger boats. Cox Lake is managed as a winterkill…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Cox Lake. 2 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — CoxFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Cox (1423)Aquatic Plant Report · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 4 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.273 m/yr | 4 |
Graded lakes near Cox Lake
Cox Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Clearwater County
Frequently asked questions about Cox Lake
What is the water quality grade for Cox Lake?
- Cox Lake in Clearwater County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 14 ft visibility. Maximum depth: 30 ft. Surface area: 60.99 acres.
Is Cox Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Cox Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
What is the water temperature of Cox Lake?
- Cox Lake typically sits around 73°F at the surface in August, from 40 EPA Water Quality Portal field readings (2016–2024). That is a typical value for the month, not a live reading.
How deep is Cox Lake?
- Cox Lake has a maximum depth of 30 feet and an average depth of 10 feet. The lake covers 60.99 acres.
What fish are in Cox Lake?
- Fish species found in Cox Lake include black crappie, bluegill, brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, yellow perch. Cox Lake is located in Clearwater County, Minnesota.
Are there boat ramps on Cox Lake?
- Cox Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Cox Lake. Public access is listed as yes.
Explore Cox Lake across LakeGrade
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Where this data comes from
14 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA14 samples · 2020–2024
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (1)
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory