Trillium Lake
Cass County, Minnesota155 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Trillium Lake. Here is what has been measured.
- Impaired · Mercury
- 48 ft max depth
- Limited data
Trillium Lake in Cass County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 11.2 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Maximum depth: 48 ft. Surface area: 155.46 acres.
Minnesota DNR's Standard Survey on June 24, 2002 caught 12.67 northern pike per gill net at Trillium Lake. Length samples in the latest survey that recorded them ran 12–33 inches. DNR survey details →
Trillium Lake is a 155-acre lake in Cass County, Minnesota with a maximum depth of 48 feet. Overall water quality is improving over recent sampling years. The lake supports 8 documented fish species including black crappie, bluegill, and brown bullhead. No public access — the lake is private or restricted.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2020-07-05. Methodology: how these readings are compared.
Trillium Lake covers about 160 acres in Cass County. The median ice-out date is April 16, which is when the open-water season begins. For a place on the water, look through cabin and lake-house rentals near Trillium Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Trillium Lake is good for
From access and monitoring records, not editorial picks.
- Clear water11.2 ft of visibility
- Fishing8 species recorded
- Ice seasonIce-out around Apr 16
- Deep water48 ft surveyed max depth
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Trillium Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Trillium 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 Trillium Lake
These are the measurements Minnesota PCA publishes for Trillium Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 11.2 ft. Phosphorus 17 µg/L. Chlorophyll-a 3.1 µg/L. TSI 43.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 11.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 17µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 3.1µg/L | Measured, not scored 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. | 43 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Trillium Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on June 24, 2002 caught 12.67 northern pike per gill net at Trillium Lake. Length samples in the latest survey that recorded them ran 12–33 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Trillium Lake’s water-quality measurements separately, and the water-quality trend over 4 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
5 surveys on file from MN DNR Fisheries. Most recent: 2002-06-24 (Standard Survey).
5 surveys on file · most recent 2002-06-24 (Standard Survey)
24 years old| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 38.33 | 3–6 in 2002-06-24 | 0.1 lb |
| Yellow Bullhead | 21.60 | 4–10 in 2002-06-24 | 0.21 lb |
| Yellow Perch | 8.34 | 5–8 in 2002-06-24 | 0.13 lb |
| Pumpkinseed | 5.84 | 3–7 in 2002-06-24 | 0.1 lb |
| Northern Pike | 4.60 | 12–33 in 2002-06-24 | 2.38 lb |
| Black Crappie | 1.94 | 5–9 in 2002-06-24 | 0.21 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.
Bluegill
Yellow Bullhead
Yellow Perch
Pumpkinseed
From the 2002-06-24 survey
Trillium Lake, also known as Lizzard Lake, is a 136-acre lake located near Hackensack, MN with no public access. With a maximum depth of 48 feet, approximately 67% of the lake is less than 15 feet deep. The Minnesota Department of Natural Resources (MNDNR) has classified Minnesota's lakes into 43 different classes…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Trillium Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — TrilliumFisheries Lake Survey · MN DNR LakeFinder
Lake Details
Max depth
48 ft
Surface area
155 acres
Shoreline
4.6 mi
Littoral zone
59%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
0 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,352 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Trillium Lake
Compare lakeside cabins, hotels, and vacation rentals near Trillium Lake in Cass 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 Trillium Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Fish Species
Click a species to see every lake where it is documented.
Fishing Trillium Lake
Water Quality Trend: Improving
Based on 4 years of monitoring (2020–2025).
Water clarity
Improving4 years
Phosphorus
Improving-1.93 µg/L/yr4 years
Chlorophyll-a
Improving-0.29 µg/L/yr4 years
Ice season
Typical ice-out
Apr 16
Earliest Apr 5, 2004 · Latest Apr 30, 2008
Most recent ice-out
Apr 30
2008
4 observations · Minnesota PCA ice records
EPA Impairment Status
Trillium 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 MN11-0270-00 · Official waterbody report
Nearby Lakes in Cass County
Frequently asked questions about Trillium Lake
Where is Trillium Lake?
- Trillium Lake is a lake in Cass County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Trillium Lake?
- Trillium Lake in Cass County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 11.2 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Maximum depth: 48 ft. Surface area: 155.46 acres.
Is Trillium Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Trillium Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Trillium Lake?
- Trillium Lake has a maximum depth of 48 feet. The lake covers 155.46 acres.
What fish are in Trillium Lake?
- Fish species found in Trillium Lake include black crappie, bluegill, brown bullhead, largemouth bass, northern pike, pumpkinseed, yellow bullhead, yellow perch. Trillium Lake is located in Cass County, Minnesota.
What did the DNR fisheries survey find at Trillium Lake?
- Minnesota DNR's Standard Survey on June 24, 2002 caught 12.67 northern pike per gill net at Trillium Lake. Length samples in the latest survey that recorded them ran 12–33 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Trillium Lake’s water-quality measurements separately, and the water-quality trend over 4 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
When does Trillium Lake thaw?
- Trillium Lake typically has ice-out around Apr 16.
Can I fish at Trillium Lake?
- Public access to Trillium 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.
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Where this data comes from
3 measurements from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA3 samples · 2020
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.
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
Ice data from Minnesota DNR Climate