Horseshoe Lake
Horseshoe Lake in Lake County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 8 ft visibility. Maximum depth: 40 ft. Surface area: 205.33 acres.
- Clarity
- 8 ft
- Typical in August
- 58°F
- Max depth
- 40 ft
- Area
- 205 acres
- Trend
- ↓ Declining
- Public access
- No
Next lake in Lake County
Why Horseshoe 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 Horseshoe Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). 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.
Horseshoe Lake is a 205-acre lake in Lake County, Minnesota with a maximum depth of 40 feet (12-foot average). Overall water quality is declining over recent sampling years. 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 2021-07-02. 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 Horseshoe Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Moderate clarity, visible to about 8 ft. Trophic State Index: 47.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 8 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 47 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Horseshoe Lake
Compare lakeside cabins, hotels, and vacation rentals near Horseshoe 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 Horseshoe Lake
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Water Temperature
Horseshoe Lake typically sits around 58°F at the surface in August. Summer average is about 58°F. Usually warmest in Aug (about 58°F) and coldest in May (about 48°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 47 field readings (2011–2025) via the EPA Water Quality Portal. See the full Horseshoe Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 40 ft |
| Average Depth | 12 ft |
| Surface Area | 205 acres |
| Shoreline Length | 5.9 mi |
| Littoral Zone | 63% |
| Public Access | No |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fishing Horseshoe Lake
DNR Fisheries Survey Summary
2 surveys on file from MN DNR Fisheries. Most recent: 2025-08-18 (Targeted Survey).
From the 2025-08-18 survey
Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Horseshoe Lake on August 18th, 2025, 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 Horseshoe Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — HorseshoeFisheries Lake Survey · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 2 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.203 m/yr | 2 |
EPA Impairment Status
Horseshoe Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MN38-0600-00 · Official waterbody report · Matched by proximity (1.78 km)
Nearby Lakes in Lake County
Frequently asked questions about Horseshoe Lake
What is the water quality grade for Horseshoe Lake?
- Horseshoe Lake in Lake County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 8 ft visibility. Maximum depth: 40 ft. Surface area: 205.33 acres.
Is Horseshoe Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Horseshoe 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 Horseshoe Lake?
- Horseshoe Lake typically sits around 58°F at the surface in August, from 47 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Horseshoe Lake?
- Horseshoe Lake has a maximum depth of 40 feet and an average depth of 12 feet. The lake covers 205.33 acres.
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Where this data comes from
1 measurement from 1 monitoring station, 2021. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA1 sample · 2021
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
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder