Mccoy Lake
Hennepin County, MinnesotaView mapDirections
Minnesota PCA publishes the water-quality measurements for Mccoy Lake. Here is what has been measured.
- Eutrophic
- Public access
- Limited data
Mccoy Lake in Hennepin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2.1 ft visibility. Phosphorus: 95 µg/L. Chlorophyll-a (algae): 8 µg/L.
Mccoy Lake is a productive, nutrient-rich eutrophic lake in Hennepin County, Minnesota. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available. Compared to the 80 other monitored lakes in Hennepin County, Mccoy Lake ranks #34 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-05-22. Methodology: how these readings are compared.
Swimming conditions
Readings onlyLimited data
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. Check local advisories before you swim.
Whether Mccoy 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 Mccoy Lake
These are the measurements Minnesota PCA publishes for Mccoy 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 2.1 ft of visibility. Phosphorus 95 µg/L. Chlorophyll-a 8 µg/L. TSI 62.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 95µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 8µg/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. | 62 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Mccoy Lake
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Stays near Mccoy Lake
Compare lakeside cabins, hotels, and vacation rentals near Mccoy Lake in Hennepin 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 Mccoy Lake are listed below.
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Fishing Mccoy Lake
Water Quality Trend: Worsening
Based on 5 years of monitoring (2020–2025).
Water clarity
Improving5 years
Phosphorus
Worsening+1.69 µg/L/yr5 years
Chlorophyll-a
Worsening+2.69 µg/L/yr5 years
Nearby Lakes in Hennepin County
Frequently asked questions about Mccoy Lake
Where is Mccoy Lake?
- Mccoy Lake is a lake in Hennepin County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Mccoy Lake?
- Mccoy Lake in Hennepin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2.1 ft visibility. Phosphorus: 95 µg/L. Chlorophyll-a (algae): 8 µg/L.
Is Mccoy Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Can I fish at Mccoy Lake?
- Public access to Mccoy 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.
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Where this data comes from
43 measurements from 1 monitoring station, 2020–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA43 samples · 2020–2023
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.