Pine Tree Lake
Washington County, MinnesotaView mapDirections
Minnesota PCA publishes the water-quality measurements for Pine Tree Lake. Here is what has been measured.
- Mesotrophic
- Eurasian watermilfoil
- 29 ft max depth
- Limited data
Pine Tree Lake in Washington County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 8.5 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 4.1 µg/L.
Pine Tree Lake is a mesotrophic lake in Washington County, Minnesota with an estimated average depth of about 29 feet. The lake supports 8 documented fish species including black bullhead, black crappie, and bluegill. No public access — the lake is private or restricted. Compared to the 74 other monitored lakes in Washington County, Pine Tree Lake ranks #17 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-10-12. Methodology: how these readings are compared.
What Pine Tree Lake is good for
From access and monitoring records, not editorial picks.
- Fishing8 species recorded
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 Pine Tree 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 Pine Tree Lake
These are the measurements Minnesota PCA publishes for Pine Tree 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 8.5 ft. Phosphorus 17 µg/L. Chlorophyll-a 4.1 µg/L. TSI 45.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 8.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 17µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 4.1µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 45 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Pine Tree Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Pine Tree Lake typically sits around 60°F at the surface in October. Summer average is about 78°F. Usually warmest in Jul (about 82°F) and coldest in Oct (about 60°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (60°F) to its warmest (82°F).
Typical surface water temperature by month, from 38 field readings (2010–2024) via the EPA Water Quality Portal. See the full Pine Tree Lake water temperature breakdown →
Lake Details
Max depth
~29 ft est.
Public access
No
Listed by Minnesota PCA
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Minnesota has not published bathymetry for Pine Tree Lake.
Lake Size & Watershed
Watershed (drainage) area
6 sq mi
HydroLAKES / HydroSHEDS
Surface area
143 acres
HydroLAKES / HydroSHEDS
Shoreline
2.7 mi
HydroLAKES / HydroSHEDS
Elevation
942 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Stays via Stay22
Stays near Pine Tree Lake
Compare lakeside cabins, hotels, and vacation rentals near Pine Tree 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.
Top-rated places to stay near Pine Tree Lake
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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 Pine Tree Lake
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Nearby Lakes in Washington County
Frequently asked questions about Pine Tree Lake
Where is Pine Tree Lake?
- Pine Tree 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 Pine Tree Lake?
- Pine Tree Lake in Washington County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 8.5 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 4.1 µg/L.
Is Pine Tree Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Pine Tree Lake?
- Pine Tree Lake typically sits around 60°F at the surface in October, from 38 EPA Water Quality Portal field readings (2010–2024). That is a typical value for the month, not a live reading.
How deep is Pine Tree Lake?
- No published bathymetric survey covers Pine Tree Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 29 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
What fish are in Pine Tree Lake?
- Fish species found in Pine Tree Lake include black bullhead, black crappie, bluegill, green sunfish, hybrid sunfish, largemouth bass, pumpkinseed, walleye. Pine Tree Lake is located in Washington County, Minnesota.
Can I fish at Pine Tree Lake?
- Public access to Pine Tree 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 Pine Tree Lake across LakeQuality
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Where this data comes from
44 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
MNPCA44 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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder