Horseshoe Lake
Horseshoe Lake in Cass County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 21 ft visibility. Maximum depth: 51 ft. Surface area: 260.32 acres.
- Clarity
- 21 ft
- Typical in August
- 74°F
- Max depth
- 51 ft
- Area
- 260 acres
- Trend
- ↑ Improving
- Public access
- Yes
- Ice-out
- Apr 21
- Open water
- 215 days
Next lake in Cass 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, 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.
Horseshoe Lake is a 260-acre lake in Cass County, Minnesota with a maximum depth of 51 feet. Overall water quality is improving over recent sampling years. The lake supports 12 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 2025-10-11. 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.
Crystal clear, you can see 21 ft down. Trophic State Index: 33.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 21 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 33 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Horseshoe Lake
Compare lakeside cabins, hotels, and vacation rentals near Horseshoe Lake in Cass 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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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
Horseshoe Lake typically sits around 74°F at the surface in August. Summer average is about 74°F. Usually warmest in Jul (about 77°F) and coldest in May (about 60°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 29 field readings (2011–2025) via the EPA Water Quality Portal. See the full Horseshoe Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Horseshoe Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (114,815 cells/mL) on November 22, 2025.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 51 ft |
| Surface Area | 260 acres |
| Shoreline Length | 3.8 mi |
| Littoral Zone | 31% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Horseshoe LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Horseshoe Lake
DNR Fisheries Survey Summary
12 surveys on file from MN DNR Fisheries. Most recent: 2024-08-05 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluntnose Minnow | 56.96 | — |
| MMS | 37.94 | — |
| BKF | 17.86 | — |
| Bluegill | 16.65 | 0.16 lb |
| Rock Bass | 15.66 | 0.21 lb |
| Yellow Perch | 13.03 | 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.
Bluegill
Rock Bass
Yellow Perch
From the 2024-08-05 survey
Horseshoe Lake is a 260-acre lake with 3.84 miles of shoreline and a maximum depth of 51 feet located east of Backus, MN. There is a MNDNR owned public access on the south shore. Horseshoe Lake is primarily managed for Bluegill, Black Crappie, Northern Pike, Largemouth Bass, and Walleye and secondarily for Yellow…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Horseshoe Lake. 3 reports 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
- —Aquatic Plant Report — Horseshoe (1525)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — HorseshoePublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.179 m/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (7 observations).
Estimated open water season: 215 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2015-04-11 (2015) | 2008-05-05 (2008) |
| Ice-In | 2014-11-15 (2014) | 2001-12-20 (2001) |
Most recent ice-out: 2019-04-24
Graded lakes near Horseshoe Lake
Horseshoe Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Cass County
Frequently asked questions about Horseshoe Lake
What is the water quality grade for Horseshoe Lake?
- Horseshoe Lake in Cass County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 21 ft visibility. Maximum depth: 51 ft. Surface area: 260.32 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 74°F at the surface in August, from 29 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 51 feet. The lake covers 260.32 acres.
What fish are in Horseshoe Lake?
- Fish species found in Horseshoe Lake include black crappie, bluegill, brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, walleye, white sucker, yellow bullhead, yellow perch. Horseshoe Lake is located in Cass County, Minnesota.
When does Horseshoe Lake thaw?
- Horseshoe Lake typically has ice-out around Apr 21. Ice typically forms around Nov 22. The open water season is approximately 215 days.
Does Horseshoe Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Horseshoe Lake (clouds, ice, or an off-season gap). The most recent reading was high (114,815 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Horseshoe Lake?
- Horseshoe Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Horseshoe Lake. Public access is listed as yes.
Explore Horseshoe Lake across LakeGrade
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Where this data comes from
100 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA100 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (2)
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
Ice data from Minnesota DNR Climate