School Grove Lake
School Grove Lake in Lyon County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1.5 ft visibility. Maximum depth: 11 ft. Surface area: 348.67 acres.
- Clarity
- 1.5 ft
- Max depth
- 11 ft
- Area
- 349 acres
- Trend
- ↓ Declining
- Public access
- Yes
Next lake in Lyon County
Why School Grove 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 School Grove 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.
School Grove Lake is a 349-acre lake in Lyon County, Minnesota with a maximum depth of 11 feet. Overall water quality is declining over recent sampling years. The lake supports 10 documented fish species including bigmouth buffalo, black bullhead, and black crappie. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-04. Grade methodology: LakeGrade methodology.
Watch School Grove 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 School Grove Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Very murky, less than 1.5 ft of visibility. Trophic State Index: 71.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.5 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 71 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Where to stay near School Grove Lake
Compare lakeside cabins, hotels, and vacation rentals near School Grove Lake in Lyon 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 School Grove 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 |
|---|---|
| Maximum Depth | 11 ft |
| Surface Area | 349 acres |
| Shoreline Length | 5 mi |
| Littoral Zone | 100% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- School Grove LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing School Grove Lake
DNR Fisheries Survey Summary
16 surveys on file from MN DNR Fisheries. Most recent: 2025-09-08 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Bullhead | 156.15 | 0.2 lb |
| Walleye | 45.63 | 1.55 lb |
| Fathead Minnow | 29.70 | — |
| Black Crappie | 11.96 | 0.38 lb |
| Bluegill | 10.92 | 0.31 lb |
| Common Carp | 8.63 | 2.64 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.
Black Bullhead
Walleye
Black Crappie
Bluegill
From the 2025-09-08 survey
A targeted fall night electrofishing survey was conducted on School Grove during September 8, 2025 to evaluate young of year "YOY" (fingerling sized) Walleye numbers due to a fry stocking. Three stations were sampled for a total of 30 minutes at night. Water temperature was 74.8 F. Water clarity was 6 inches. We saw…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for School Grove Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — School GroveFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — School GroveFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — School GrovePublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 4 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.044 m/yr | 4 |
EPA Impairment Status
School Grove Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN42-0002-00 · Official waterbody report
Graded lakes near School Grove Lake
School Grove Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Lyon County
Frequently asked questions about School Grove Lake
What is the water quality grade for School Grove Lake?
- School Grove Lake in Lyon County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1.5 ft visibility. Maximum depth: 11 ft. Surface area: 348.67 acres.
Is School Grove Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. School Grove Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is School Grove Lake?
- School Grove Lake has a maximum depth of 11 feet. The lake covers 348.67 acres.
What fish are in School Grove Lake?
- Fish species found in School Grove Lake include bigmouth buffalo, black bullhead, black crappie, common carp, green sunfish, orangespotted sunfish, walleye, white sucker, yellow bullhead, yellow perch. School Grove Lake is located in Lyon County, Minnesota.
Are there boat ramps on School Grove Lake?
- School Grove Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include School Grove Lake. Public access is listed as yes.
Explore School Grove Lake across LakeGrade
Depth, room, public access, and the state wake-sport rules
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in Lyon County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its grade
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near School Grove Lake
Other Lakes in Minnesota
Hypereutrophic Lakes in Minnesota
Where this data comes from
27 measurements from 1 monitoring station, 2022–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA27 samples · 2022–2025
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
Named boat-access points from the USGS National Boat Ramps inventory