Minerva Lake
Clearwater County, Minnesota230 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Minerva Lake. Here is what has been measured.
- Eutrophic
- Impaired · Mercury
- 16 ft max depth
- Public access
Minerva Lake in Clearwater County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 7.5 µg/L. Maximum depth: 16 ft. Surface area: 230.02 acres.
Minnesota DNR's Standard Survey on June 27, 2016 caught 4.33 walleye per gill net at Minerva Lake. DNR survey details →
Minerva Lake is a 230-acre productive, nutrient-rich eutrophic lake in Clearwater County, Minnesota with a maximum depth of 16 feet (8-foot average). Overall water quality is improving over recent sampling years. The lake supports 11 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 36 other monitored lakes in Clearwater County, Minerva Lake ranks #30 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-09. Methodology: how these readings are compared.
What Minerva Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing11 species recorded
Swimming conditions
Readings onlyModerate algae
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Minerva Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Minerva Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Minerva Lake
These are the measurements Minnesota PCA publishes for Minerva Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 7 ft. Phosphorus 26 µg/L. Chlorophyll-a 7.5 µg/L. TSI 50.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 26µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 7.5µg/L | Fair GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 50 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Minerva Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Minerva Lake typically sits around 64°F at the surface in September. Summer average is about 72°F. Usually warmest in Jul (about 75°F) and coldest in Sep (about 64°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (64°F) to its warmest (75°F).
Typical surface water temperature by month, from 131 field readings (2018–2025) via the EPA Water Quality Portal. See the full Minerva Lake water temperature breakdown →
Minnesota DNR's Standard Survey on June 27, 2016 caught 4.33 walleye per gill net at Minerva Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Minerva Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
7 surveys on file from MN DNR Fisheries. Most recent: 2016-06-27 (Standard Survey).
7 surveys on file · most recent 2016-06-27 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 29.23 | 5–10 in 2016-06-27 | 0.27 lb |
| Black Bullhead | 23.15 | 8–12 in 2016-06-27 | 0.6 lb |
| Brown Bullhead | 10.09 | 8–14 in 2016-06-27 | 0.87 lb |
| Bluegill | 7.70 | 3–10 in 2016-06-27 | 0.45 lb |
| Pumpkinseed | 6.43 | 3–8 in 2016-06-27 | 0.24 lb |
| Largemouth Bass | 5.14 | 12–19 in 2016-06-27 | 1.55 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
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.
Yellow Perch
Black Bullhead
Brown Bullhead
Bluegill
From the 2016-06-27 survey
Lake Minerva is a 230-acre lake with a maximum depth of 16 feet located 12 miles south of Bagley in Clearwater County. There is a DNR public water access located on the southeast shore of the lake with an earthen ramp and parking for about 8 trucks/trailers. Lake Minerva is managed for Walleye, Black Crappie, and…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Minerva Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — MinervaFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Minerva (1698)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — MinervaFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — MinervaPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
16 ft
Average depth
7.9 ft
Surface area
230 acres
Shoreline
2.8 mi
Littoral zone
95%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
2 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,496 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Minerva LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Minerva Lake
Compare lakeside cabins, hotels, and vacation rentals near Minerva Lake in Clearwater 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 Minerva Lake
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Fish Species
Click a species to see every lake where it is documented.
Fishing Minerva Lake
Water Quality Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Stable-0.07 µg/L/yr6 years
Chlorophyll-a
Improving-0.22 µg/L/yr6 years
Reservoir Info (USACE NID)
Minerva Lake is a man-made reservoir impounded by the Upper Rice Lake (completed 1968), built primarily for fish and wildlife pond on the Wild Rice River; gravity-type dam, 7 ft tall and 26 ft long.
- Normal storage
- 11,160 ac-ft
- Max storage
- 14,880 ac-ft
- Drainage area
- 14.3 sq mi
- Hazard class
- Low
- Owner
- MNDNR-Wildlife
Source: USACE National Inventory of Dams, NID ID MN00231 · Operator website · Matched by proximity (0.82 km)
EPA Impairment Status
Minerva Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN15-0079-00 · Official waterbody report
Nearby Lakes in Clearwater County
Frequently asked questions about Minerva Lake
Where is Minerva Lake?
- Minerva Lake is a lake in Clearwater County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Minerva Lake?
- Minerva Lake in Clearwater County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 7.5 µg/L. Maximum depth: 16 ft. Surface area: 230.02 acres.
Is Minerva Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Minerva Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
What is the water temperature of Minerva Lake?
- Minerva Lake typically sits around 64°F at the surface in September, from 131 EPA Water Quality Portal field readings (2018–2025). That is a typical value for the month, not a live reading.
How deep is Minerva Lake?
- Minerva Lake has a maximum depth of 16 feet and an average depth of 7.9 feet. The lake covers 230.02 acres.
What fish are in Minerva Lake?
- Fish species found in Minerva Lake include black bullhead, black crappie, bluegill, brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, white sucker, yellow perch. Minerva Lake is located in Clearwater County, Minnesota.
What did the DNR fisheries survey find at Minerva Lake?
- Minnesota DNR's Standard Survey on June 27, 2016 caught 4.33 walleye per gill net at Minerva Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Minerva Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Minerva Lake?
- Minerva Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Minerva Lake. Public access is listed as yes.
Can I fish at Minerva Lake?
- Minerva Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Minerva Lake across LakeQuality
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Where this data comes from
87 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA87 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from 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