Topaz Lake
Lake County, Minnesota410 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Topaz Lake. Here is what has been measured.
- 110 ft max depth
- Limited data
Topaz Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 17.6 ft visibility. Maximum depth: 110 ft. Surface area: 409.8 acres.
Minnesota DNR's Standard Survey on September 10, 2018 caught 0.80 smallmouth bass per gill net at Topaz Lake. Length samples in the latest survey that recorded them ran 5–10 inches. DNR survey details →
Topaz Lake is a 410-acre lake in Lake County, Minnesota with a maximum depth of 110 feet. The lake supports 4 documented fish species including burbot, cisco species, and lake trout. No public access — the lake is private or restricted.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-07-19. Methodology: how these readings are compared.
What Topaz Lake is good for
From access and monitoring records, not editorial picks.
- Clear water17.6 ft of visibility
- Fishing4 species recorded
- Deep water110 ft surveyed max depth
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Topaz 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 Topaz Lake
These are the measurements Minnesota PCA publishes for Topaz Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 17.6 ft down. TSI 36.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 17.6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 36 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Topaz Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on September 10, 2018 caught 0.80 smallmouth bass per gill net at Topaz Lake. Length samples in the latest survey that recorded them ran 5–10 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Topaz Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
4 surveys on file from MN DNR Fisheries. Most recent: 2025-08-01 (Targeted Survey).
4 surveys on file · most recent 2025-08-01 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Tullibee (Cisco) | 37.52 | 0.32 lb | |
| Lake Trout | 1.27 | 16–32 in 2018-09-10 | 6.04 lb |
| Smallmouth Bass | 0.80 | 5–10 in 2018-09-10 | 0.21 lb |
| Walleye | 0.67 | 2.38 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.
Lake Trout
Smallmouth Bass
From the 2025-08-01 survey
Temperature and dissolved oxygen measurements were collected from the deepest basin in Amoeber Lake on August 1st, 2025. This was done to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Trout, the most sensitive coldwater species present in this lake (Cisco,…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Topaz Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — AmoeberFisheries Lake Survey · MN DNR LakeFinder
Lake Details
Max depth
110 ft
Surface area
410 acres
Shoreline
10.1 mi
Littoral zone
26%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
2 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,437 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Topaz Lake
Compare lakeside cabins, hotels, and vacation rentals near Topaz 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 Topaz Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Follow Topaz Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Topaz Lake
Water Quality Trend: Stable
Based on 5 years of monitoring (2020–2025).
Water clarity
Stable5 years
Nearby Lakes in Lake County
Frequently asked questions about Topaz Lake
Where is Topaz Lake?
- Topaz 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 Topaz Lake?
- Topaz Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 17.6 ft visibility. Maximum depth: 110 ft. Surface area: 409.8 acres.
Is Topaz Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Topaz Lake?
- Topaz Lake has a maximum depth of 110 feet. The lake covers 409.8 acres.
What fish are in Topaz Lake?
- Fish species found in Topaz Lake include burbot, cisco species, lake trout, smallmouth bass. Topaz Lake is located in Lake County, Minnesota.
What did the DNR fisheries survey find at Topaz Lake?
- Minnesota DNR's Standard Survey on September 10, 2018 caught 0.80 smallmouth bass per gill net at Topaz Lake. Length samples in the latest survey that recorded them ran 5–10 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Topaz Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
Can I fish at Topaz Lake?
- Public access to Topaz 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 Topaz Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
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Fish species and best lakes in Lake County
Species activity outlook by water temperature and season
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Where this data comes from
10 measurements from 5 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA10 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (5)
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