Millstone Lake
Wright County, Minnesota200 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Millstone Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Nutrients (phosphorus, nitrogen)
- 9 ft max depth
- Public access
- Limited data
Millstone Lake in Wright County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 0.8 ft visibility. Phosphorus: 186 µg/L. Chlorophyll-a (algae): 62.8 µg/L. Maximum depth: 8.5 ft. Surface area: 199.63 acres.
Minnesota DNR's Targeted Survey on May 7, 2019 caught 0.25 black crappie per trap net at Millstone Lake. DNR survey details →
Millstone Lake is a 200-acre highly nutrient-loaded hypereutrophic lake in Wright County, Minnesota with a maximum depth of 9 feet (4-foot average). The lake supports 4 documented fish species including black bullhead, black crappie, and bluegill. Public access is available. Compared to the 50 other monitored lakes in Wright County, Millstone Lake ranks #45 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2022-10-12. Methodology: how these readings are compared.
What Millstone Lake is good for
From access and monitoring records, not editorial picks.
- Fishing4 species recorded
Swimming conditions
Readings onlyRecreation use not supported
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. Millstone Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Millstone 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 Millstone Lake
These are the measurements Minnesota PCA publishes for Millstone Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 0.8 ft of visibility. Phosphorus 186 µg/L. Chlorophyll-a 62.8 µg/L. TSI 77.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 0.8ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 186µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 62.8µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 77 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Millstone Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Millstone Lake typically sits around 74°F at the surface in October. Summer average is about 72°F. Usually warmest in Jun (about 75°F) and coldest in Sep (about 62°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (62°F) to its warmest (75°F).
Typical surface water temperature by month, from 62 field readings (2022–2022) via the EPA Water Quality Portal. See the full Millstone Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on May 7, 2019 caught 0.25 black crappie per trap net at Millstone Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Millstone Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
1 survey on file from MN DNR Fisheries. Most recent: 2019-05-07 (Targeted Survey).
1 survey on file · most recent 2019-05-07 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 12.50 | ||
| Black Bullhead | 8.75 | ||
| Green Sunfish | 2.75 | ||
| Black Crappie | 0.25 |
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.
From the 2019-05-07 survey
Millstone Lake is located four miles north of Maple Lake in Wright County. It has a surface area of 202 acres and a maximum depth of eight to ten feet depending on water levels. The watershed is small (705 acres) mostly agricultural, and water quality is poor. Millstone Lake has not been considered to be a "fish lake"…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Millstone Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — MillstoneFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Millstone (2011)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — MillstonePublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
8.5 ft
Average depth
4.2 ft
Surface area
200 acres
Shoreline
2.6 mi
Littoral zone
100%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
2 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,020 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Millstone Lake
Compare lakeside cabins, hotels, and vacation rentals near Millstone Lake in Wright 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Millstone Lake are listed below.
Top-rated places to stay near Millstone Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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 →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Millstone Lake
EPA Impairment Status
Millstone Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN86-0152-00 · Official waterbody report
Nearby Lakes in Wright County
Frequently asked questions about Millstone Lake
Where is Millstone Lake?
- Millstone Lake is a lake in Wright County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Millstone Lake?
- Millstone Lake in Wright County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 0.8 ft visibility. Phosphorus: 186 µg/L. Chlorophyll-a (algae): 62.8 µg/L. Maximum depth: 8.5 ft. Surface area: 199.63 acres.
Is Millstone Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Millstone Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Millstone Lake?
- Millstone Lake typically sits around 74°F at the surface in October, from 62 EPA Water Quality Portal field readings (2022–2022). That is a typical value for the month, not a live reading.
How deep is Millstone Lake?
- Millstone Lake has a maximum depth of 8.5 feet and an average depth of 4.2 feet. The lake covers 199.63 acres.
What fish are in Millstone Lake?
- Fish species found in Millstone Lake include black bullhead, black crappie, bluegill, green sunfish. Millstone Lake is located in Wright County, Minnesota.
What did the DNR fisheries survey find at Millstone Lake?
- Minnesota DNR's Targeted Survey on May 7, 2019 caught 0.25 black crappie per trap net at Millstone Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Millstone Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
Can I fish at Millstone Lake?
- Public access to Millstone Lake is listed as yes on the lake record. 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 Millstone Lake across LakeQuality
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Where this data comes from
40 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
MNPCA40 samples · 2022
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