Tetagouche Lake
Lake County, Minnesota67 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Tetagouche Lake. Here is what has been measured.
- Mesotrophic
- Impaired · Mercury
- 20 ft max depth
Tetagouche Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7.2 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 4.8 µg/L. Maximum depth: 20 ft. Surface area: 66.56 acres.
Minnesota DNR's Standard Survey on July 11, 2022 caught 12.67 northern pike per gill net at Tetagouche Lake. Length samples in the latest survey that recorded them ran 10–28 inches. DNR survey details →
Tetagouche Lake is a 67-acre mesotrophic lake in Lake County, Minnesota with a maximum depth of 20 feet. Overall water quality is declining over recent sampling years. The lake supports 2 documented fish species including northern pike and yellow perch. No public access — the lake is private or restricted. Compared to the 34 other monitored lakes in Lake County, Tetagouche Lake ranks #11 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-09-07. Methodology: how these readings are compared.
Tetagouche Lake covers about 67 acres in Lake County. If you are planning to stay, you can search lake houses and cabins around Tetagouche Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
Swimming conditions
Readings onlyLow 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. Tetagouche Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Tetagouche 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 Tetagouche Lake
These are the measurements Minnesota PCA publishes for Tetagouche 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 7.2 ft. Phosphorus 17 µg/L. Chlorophyll-a 4.8 µg/L. TSI 47.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7.2ft | 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) | 4.8µg/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. | 47 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Tetagouche Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Tetagouche Lake typically sits around 67°F at the surface in September. Summer average is about 70°F. Usually warmest in Jul (about 72°F) and coldest in May (about 57°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (57°F) to its warmest (72°F).
Typical surface water temperature by month, from 43 field readings (2022–2023) via the EPA Water Quality Portal. See the full Tetagouche Lake water temperature breakdown →
Minnesota DNR's Standard Survey on July 11, 2022 caught 12.67 northern pike per gill net at Tetagouche Lake. Length samples in the latest survey that recorded them ran 10–28 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Tetagouche Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
6 surveys on file from MN DNR Fisheries. Most recent: 2022-07-11 (Standard Survey).
6 surveys on file · most recent 2022-07-11 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 12.26 | 1–8 in 2022-07-11 | 0.13 lb |
| Northern Pike | 6.98 | 10–28 in 2022-07-11 | 2.15 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
Northern Pike
From the 2022-07-11 survey
Tettagouche Lake is a 67 acre lake with a maximum depth of 20 feet located entirely within Tettagouche State Park. Minnesota residents do not need a fishing license to fish on the lake because the lake is completely contained within a state park, but must comply with all other fishing regulations. Motorized watercraft…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Tetagouche Lake. 2 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — TetagoucheFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Tetagouche (0768)Aquatic Plant Report · MN DNR LakeFinder
Lake Details
Max depth
20 ft
Surface area
67 acres
Shoreline
1.8 mi
Littoral zone
99%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
0 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,306 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Tetagouche Lake
Compare lakeside cabins, hotels, and vacation rentals near Tetagouche Lake in Lake 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 Tetagouche Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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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 Tetagouche Lake
Water quality readings over time
2 seasons of samples on record (2022–2023). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Worsening2 years
Phosphorus
Worsening+3 µg/L/yr2 years
Chlorophyll-a
Worsening+0.2 µg/L/yr2 years
EPA Impairment Status
Tetagouche 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 MN38-0231-00 · Official waterbody report
Nearby Lakes in Lake County
Frequently asked questions about Tetagouche Lake
Where is Tetagouche Lake?
- Tetagouche Lake is a lake in Lake County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Tetagouche Lake?
- Tetagouche Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7.2 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 4.8 µg/L. Maximum depth: 20 ft. Surface area: 66.56 acres.
Is Tetagouche Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Tetagouche 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 Tetagouche Lake?
- Tetagouche Lake typically sits around 67°F at the surface in September, from 43 EPA Water Quality Portal field readings (2022–2023). That is a typical value for the month, not a live reading.
How deep is Tetagouche Lake?
- Tetagouche Lake has a maximum depth of 20 feet. The lake covers 66.56 acres.
What fish are in Tetagouche Lake?
- Fish species found in Tetagouche Lake include northern pike, yellow perch. Tetagouche Lake is located in Lake County, Minnesota.
What did the DNR fisheries survey find at Tetagouche Lake?
- Minnesota DNR's Standard Survey on July 11, 2022 caught 12.67 northern pike per gill net at Tetagouche Lake. Length samples in the latest survey that recorded them ran 10–28 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Tetagouche Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
Can I fish at Tetagouche Lake?
- Public access to Tetagouche 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 Tetagouche Lake across LakeQuality
2 documented falls within 16.5 mi, nearest High Falls of the Baptism River
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Species activity outlook by water temperature and season
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Minnesota's cleanest lakes, ranked on agency measurements
Planning a trip around Apostle Islands?
Tetagouche Lake is about 39 miles from Apostle Islands National Lakeshore. Crowds there swing hard by season, so the month you pick changes both how busy the park is and what lodging costs.
Best time to visit Apostle Islands →More lakes in Minnesota
State Parks Near Tetagouche Lake
Other Lakes in Minnesota
Mesotrophic Lakes in Minnesota
Where this data comes from
45 measurements from 1 monitoring station, 2022–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA45 samples · 2022–2023
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 2130 B ~ Nephelometric Method
- 2120 B ~ Color in Water by Visual Comparison
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