Markham Lake
Markham Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 3 ft visibility. Maximum depth: 29 ft. Surface area: 229.16 acres.
- Clarity
- 3 ft
- Typical in August
- 72°F
- Max depth
- 29 ft
- Area
- 229 acres
- Public access
- No
Next lake in St. Louis County
Why Markham 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 Markham 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.
Markham Lake is a 229-acre lake in St. Louis County, Minnesota with a maximum depth of 29 feet. 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 2023-08-30. 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 Markham Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Very murky, less than 3 ft of visibility. Trophic State Index: 61.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 61 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Markham Lake
Compare lakeside cabins, hotels, and vacation rentals near Markham Lake in St. Louis 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 Markham Lake
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
Markham Lake typically sits around 72°F at the surface in August. Summer average is about 73°F. Usually warmest in Jul (about 75°F) and coldest in May (about 65°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 9 field readings (2023–2023) via the EPA Water Quality Portal. See the full Markham Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 29 ft |
| Surface Area | 229 acres |
| Shoreline Length | 3.7 mi |
| Littoral Zone | 100% |
| Public Access | No |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fishing Markham Lake
DNR Fisheries Survey Summary
1 survey on file from MN DNR Fisheries. Most recent: 1974-08-12 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Crappie | 5.88 | 0.14 lb |
| White Sucker | 1.88 | 2.73 lb |
| Bluegill | 1.25 | 0.45 lb |
| Northern Pike | 0.50 | 0.5 lb |
| Pumpkinseed | 0.50 | 0.3 lb |
| Yellow Perch | 0.50 | 0.45 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
From the 1974-08-12 survey
Fish populations are low with the exception of Crappies which are adequate.
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Markham Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — MarkhamFisheries Lake Survey · MN DNR LakeFinder
Graded lakes near Markham Lake
Markham Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in St. Louis County
Frequently asked questions about Markham Lake
What is the water quality grade for Markham Lake?
- Markham Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 3 ft visibility. Maximum depth: 29 ft. Surface area: 229.16 acres.
Is Markham Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Markham 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 Markham Lake?
- Markham Lake typically sits around 72°F at the surface in August, from 9 EPA Water Quality Portal field readings (2023–2023). That is a typical value for the month, not a live reading.
How deep is Markham Lake?
- Markham Lake has a maximum depth of 29 feet. The lake covers 229.16 acres.
Explore Markham Lake across LakeGrade
Depth, room, public access, and the state wake-sport rules
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Species activity outlook by water temperature and season
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Where this data comes from
9 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA9 samples · 2023
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