Mud Lake
Mud Lake in Otter Tail County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1.3 ft visibility. Phosphorus: 87 µg/L. Chlorophyll-a (algae): 52.8 µg/L.
- Clarity
- 1.3 ft
- Mean depth
- ~11 ft est.
- Public access
- No
Next lake in Otter Tail County
Why Mud 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 Mud Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, 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.
Mud Lake is a lake in Otter Tail County, Minnesota with an estimated average depth of about 11 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 2022-07-13. Grade methodology: LakeGrade methodology.
Watch Mud Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Mud Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Very murky, less than 1.3 ft of visibility. Phosphorus level: 87 µg/L. Chlorophyll-a: 52.8 µg/L. Trophic State Index: 70.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.3 ft | Not graded |
| Phosphorus | 87 µg/L | Not graded |
| Chlorophyll-a (Algae) | 52.8 µg/L | Not graded |
| Trophic State Index (TSI) | 70 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Where to stay near Mud Lake
Compare lakeside cabins, hotels, and vacation rentals near Mud Lake in Otter Tail 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 Mud Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Minnesota’s top lakes →
Lake Details
| Characteristic | Value |
|---|---|
| Average Depth | ~11 ft est. |
| Public Access | No |
Depth marked “est.” is a modeled estimate from HydroLAKES, not a measured survey. Minnesota has not published bathymetry for Mud Lake.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Fishing Mud Lake
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Mud Lake under Clean Water Act (NPDES) discharge permits.
- Dalton WwtfDalton · 2.6 mi away · NPDES MN0023141
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Graded lakes near Mud Lake
Mud Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Otter Tail County
Frequently asked questions about Mud Lake
What is the water quality grade for Mud Lake?
- Mud Lake in Otter Tail County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1.3 ft visibility. Phosphorus: 87 µg/L. Chlorophyll-a (algae): 52.8 µg/L.
Is Mud Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Mud Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Algae concentration (chlorophyll-a) is 52.8 µg/L. Always check local health department advisories before swimming.
How deep is Mud Lake?
- No published bathymetric survey covers Mud Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 11 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Explore Mud Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in Otter Tail County
Species activity outlook by water temperature and season
Top lakes and where to stay in the Alexandria Lakes area
Top lakes and where to stay in the Detroit Lakes Area area
Top lakes and where to stay in the Otter Tail County area
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Red River of the North Watershed, ranked by water quality
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Mud Lake
Other Lakes in Minnesota
Hypereutrophic Lakes in Minnesota
Where this data comes from
4 measurements from 1 monitoring station, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA4 samples · 2022
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 2120 B ~ Color in Water by Visual Comparison
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder