Mt Maud Lake Mid Basin
Cook County, MinnesotaLimited DataEutrophic
Mt Maud Lake Mid Basin grades an F: water clarity, phosphorus, and chlorophyll-a all rate poorly, placing it among the most stressed lakes monitored in Minnesota. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.
A TSI in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Mt Maud Lake Mid Basin ranks 111 of 128 in Cook County — at the lower end of the locally monitored distribution.
No invasive species are currently listed at Mt Maud Lake Mid Basin — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Mt Maud Lake Mid Basin, which usually reflects a lack of formal fisheries survey work rather than an empty lake. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2021-09-21. Grade methodology: LakeGrade methodology.
Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
Very murky, less than 2.5 ft of visibility. Trophic State Index: 64.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.5 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 64 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Water Quality Trend: ↑ Improving
Based on 3 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.05 m/yr | 3 |
| Phosphorus | ↑ Improving | -1.5 µg/L/yr | 2 |
| Chlorophyll-a | ↑ Improving | -1.05 µg/L/yr | 2 |
Location
County Ranking
Ranked #111 of 128 lakes in Cook County
Cleaner Lakes Within 30 Miles
Mt Maud Lake Mid Basin holds Grade F. 2 nearby lakes hold higher grades.
- CMt Maud LakeCook County · 0.2 mi · Two grade letters higher (F → C)
- DDutchman Lake DeepCook County · 1.1 mi · Higher grade (F → D)
Nearby Lakes in Cook County
More Minnesota Lake Rankings
State Parks Near Mt Maud Lake Mid Basin
Other Grade F Lakes in Minnesota
Eutrophic Lakes in Minnesota
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2021-09-21
Monitoring stations: 1