Heikkilla Lake
Heikkilla Lake in St. Louis County, Minnesota has a water quality grade of C (Fair). Water clarity: 5 ft visibility. Phosphorus: 24 µg/L. Chlorophyll-a (algae): 13.6 µg/L. Maximum depth: 7 ft. Surface area: 129.6 acres.
- Clarity
- 5 ft
- Typical in August
- 69°F
- Max depth
- 7 ft
- Area
- 130 acres
- Type
- Eutrophic
- Trend
- ↑ Improving
- Public access
- No
- Ice-out
- Apr 21
Next lake in St. Louis County
Heikkilla Lake is a 130-acre productive, nutrient-rich eutrophic lake in St. Louis County, Minnesota with a maximum depth of 7 feet. Water quality is graded C based on 2 sampling years through 2025. Overall water quality is improving over recent sampling years. The lake supports 6 documented fish species including black bullhead, brown bullhead, and northern pike. No public access — the lake is private or restricted. Compared to the 67 other monitored lakes in St. Louis County, Heikkilla Lake ranks #55 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-23. Grade methodology: LakeGrade methodology.
Watch Heikkilla Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Grade onlyModerate
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Generally safe for swimming, moderate water quality
Water Quality Grade: C (Fair)
Murky, only visible to about 5 ft. Phosphorus level: 24 µg/L. Chlorophyll-a: 13.6 µg/L. Trophic State Index: 53.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 5 ft | Not graded |
| Phosphorus | 24 µg/L | Good |
| Chlorophyll-a (Algae) | 13.6 µg/L | Fair |
| Trophic State Index (TSI) | 53 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Heikkilla Lake
Compare lakeside cabins, hotels, and vacation rentals near Heikkilla Lake in St. Louis 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 Heikkilla Lake
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 →
Water Temperature
Heikkilla Lake typically sits around 69°F at the surface in August. Summer average is about 70°F. Usually warmest in Jul (about 72°F) and coldest in Sep (about 57°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 39 field readings (2024–2025) via the EPA Water Quality Portal. See the full Heikkilla Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 7 ft |
| Surface Area | 130 acres |
| Shoreline Length | 2.3 mi |
| Littoral Zone | 100% |
| Public Access | No |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Heikkilla Lake
DNR Fisheries Survey Summary
1 survey on file from MN DNR Fisheries. Most recent: 2019-07-22 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Pumpkinseed | 105.00 | — |
| Yellow Perch | 69.28 | 0.32 lb |
| GOS | 61.80 | 0.08 lb |
| Black Bullhead | 48.09 | 0.06 lb |
| TPM | 21.50 | — |
| BNS | 13.00 | — |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
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
GOS
Black Bullhead
From the 2019-07-22 survey
Heikkilla Lake is located approximately 1.5 miles SE of Embarrass within the Superior National Forest. This shallow lake is surrounded by private land and no public access is present. The 2019 survey of Heikkilla Lake represents the first time this lake has been sampled by DNR Fisheries. Black bullheads dominated the…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Heikkilla Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — HeikkillaFisheries Lake Survey · MN DNR LakeFinder
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.024 m/yr | 6 |
| Phosphorus | ↑ Improving | -4.5 µg/L/yr | 2 |
| Chlorophyll-a | ↑ Improving | -13.4 µg/L/yr | 2 |
Ice Season
Historical ice data from Minnesota DNR (6 observations).
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2021-04-05 (2021) | 2014-05-07 (2014) |
Most recent ice-out: 2023-05-03
Regulated Pollution Sources Nearby
3 EPA-permitted facilities operate within about 5 miles of Heikkilla Lake under Clean Water Act (NPDES) discharge permits.
- Ltv Steel/Ltv Corp-TailingsHoyt Lakes · 3.3 mi away · NPDES MN0054089
- Poly Met Mining, Inc.Hoyt Lakes · 3.7 mi away · NPDES MN0071013
- Hoyt Lakes Mining AreaHoyt Lakes · 3.8 mi away · NPDES MN0042536
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
County Ranking
Ranked #55 of 68 lakes in St. Louis County
Nearby Lakes With Higher Grades
Heikkilla Lake holds Grade C. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in St. Louis County
Frequently asked questions about Heikkilla Lake
What is the water quality grade for Heikkilla Lake?
- Heikkilla Lake in St. Louis County, Minnesota has a water quality grade of C (Fair). Water clarity: 5 ft visibility. Phosphorus: 24 µg/L. Chlorophyll-a (algae): 13.6 µg/L. Maximum depth: 7 ft. Surface area: 129.6 acres.
Is Heikkilla Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Heikkilla Lake has a water quality grade of C (Fair). Algae concentration (chlorophyll-a) is 13.6 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Heikkilla Lake?
- Heikkilla Lake typically sits around 69°F at the surface in August, from 39 EPA Water Quality Portal field readings (2024–2025). That is a typical value for the month, not a live reading.
How deep is Heikkilla Lake?
- Heikkilla Lake has a maximum depth of 7 feet. The lake covers 129.6 acres.
What fish are in Heikkilla Lake?
- Fish species found in Heikkilla Lake include black bullhead, brown bullhead, northern pike, pumpkinseed, white sucker, yellow perch. Heikkilla Lake is located in St. Louis County, Minnesota.
When does Heikkilla Lake thaw?
- Heikkilla Lake typically has ice-out around Apr 21.
Explore Heikkilla Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in St. Louis County
Species activity outlook by water temperature and season
Top lakes and where to stay in the Lake Vermilion Area area
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Lake Superior Basin (MN+WI), ranked by water quality
Lakes in the Rainy Lake Watershed, ranked by water quality
High nutrients, frequent algae, reduced clarity
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Heikkilla Lake
Other Grade C Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
59 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA59 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate