Fish Lake
Washington County, Minnesota21 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Fish Lake. Here is what has been measured.
- Eutrophic
- Impaired · Nutrients (phosphorus, nitrogen)
- 34 ft max depth
- Limited data
Fish Lake in Washington County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 6 ft visibility. Phosphorus: 42 µg/L. Chlorophyll-a (algae): 12 µg/L. Maximum depth: 34 ft. Surface area: 20.7 acres.
Fish Lake is a 21-acre productive, nutrient-rich eutrophic lake in Washington County, Minnesota with a maximum depth of 34 feet. Limited fish-species data available. No public access — the lake is private or restricted. Compared to the 74 other monitored lakes in Washington County, Fish Lake ranks #50 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-10-21. Methodology: how these readings are compared.
What Fish Lake is good for
From access and monitoring records, not editorial picks.
- Deep water34 ft surveyed max depth
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. Fish Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Fish 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 Fish Lake
These are the measurements Minnesota PCA publishes for Fish Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 6 ft. Phosphorus 42 µg/L. Chlorophyll-a 12 µg/L. TSI 55.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 42µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 12µg/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. | 55 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Fish Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Fish Lake typically sits around 54°F at the surface in October. Summer average is about 62°F. Usually warmest in Aug (about 65°F) and coldest in May (about 49°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (49°F) to its warmest (65°F).
Typical surface water temperature by month, from 149 field readings (2011–2024) via the EPA Water Quality Portal. See the full Fish Lake water temperature breakdown →
Lake Details
Max depth
34 ft
Surface area
21 acres
Shoreline
0.8 mi
Littoral zone
68%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Stays via Stay22
Stays near Fish Lake
Compare lakeside cabins, hotels, and vacation rentals near Fish Lake in Washington 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 Fish Lake are listed below.
Top-rated places to stay near Fish 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 →
Follow Fish Lake’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing Fish Lake
EPA Impairment Status
Fish 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.
Source: EPA ATTAINS assessment unit MN82-0137-00 · Official waterbody report
Nearby Lakes in Washington County
Frequently asked questions about Fish Lake
Where is Fish Lake?
- Fish Lake is a lake in Washington County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Fish Lake?
- Fish Lake in Washington County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 6 ft visibility. Phosphorus: 42 µg/L. Chlorophyll-a (algae): 12 µg/L. Maximum depth: 34 ft. Surface area: 20.7 acres.
Is Fish Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Fish 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 Fish Lake?
- Fish Lake typically sits around 54°F at the surface in October, from 149 EPA Water Quality Portal field readings (2011–2024). That is a typical value for the month, not a live reading.
How deep is Fish Lake?
- Fish Lake has a maximum depth of 34 feet. The lake covers 20.7 acres.
Can I fish at Fish Lake?
- Public access to Fish Lake is listed as no on the lake record, so confirm before you make the trip. 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 Fish Lake across LakeQuality
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Washington County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the St. Croix Watershed, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
More lakes in Minnesota
State Parks Near Fish Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
56 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA56 samples · 2024
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- Analysis of Chlorophyll in Periphyton and Plankton
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 details from Minnesota DNR LakeFinder