Skip to main content
LakeQuality

Spearhead Lake

NR
Not yet rated
15 ft clear · Oligotrophic · 194 acres
Limited DataOligotrophic

Spearhead Lake in Hubbard County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 15 ft visibility. Maximum depth: 81 ft. Surface area: 194.36 acres.

Clarity
15 ft
Typical in August
56°F
Max depth
81 ft
Area
194 acres
Trend
Declining
Public access
No
Ice-out
Apr 15
Open water
223 days

Next lake in Hubbard County

ANewman Lake17.1 ft clear · Hubbard CountyView →
Loading map…

Why Spearhead Lake has no grade

We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Spearhead Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).

Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.

Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.

Spearhead Lake is a 194-acre lake in Hubbard County, Minnesota with a maximum depth of 81 feet. Overall water quality is declining over recent sampling years. The lake supports 17 documented fish species including black bullhead, black crappie, and bluegill. No public access — the lake is private or restricted.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-29. Grade methodology: LakeGrade methodology.

Watch Spearhead Lake water quality

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Not rated

Limited data

Not rated for swimming — there is not enough monitoring data to judge this lake

Compare the safest swimming lakes near Bemidji

Get alerts for Spearhead Lake

Water quality measurements for Spearhead Lake

These readings exist but do not meet the evidence bar for an A–F grade — see why.

Crystal clear, you can see 15 ft down. Trophic State Index: 38.

MetricValueGrade
Water Clarity (Secchi Depth)15 ftNot graded
PhosphorusNo recent samples
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)38Oligotrophic

Low nutrients, clear water, excellent for swimming

Where to stay near Spearhead Lake

Compare lakeside cabins, hotels, and vacation rentals near Spearhead Lake in Hubbard 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 Spearhead 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

Spearhead Lake typically sits around 56°F at the surface in August. Summer average is about 61°F. Usually warmest in Jun (about 66°F) and coldest in May (about 56°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
Apr
May
56°
Jun
66°
Jul
60°
Aug
56°
Sep
66°
Oct
56°
Nov
Dec

Typical surface water temperature by month, from 179 field readings (20222025) via the EPA Water Quality Portal. See the full Spearhead Lake water temperature breakdown →

Lake Details

CharacteristicValue
Maximum Depth81 ft
Surface Area194 acres
Shoreline Length3.9 mi
Littoral Zone11%
Public AccessNo

Lake Size & Watershed

Watershed (drainage) area
7 sq mi
Elevation
1,348 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).

Fish Species

Click a species to see every graded lake where it is documented.

Fishing Spearhead Lake

DNR Fisheries Survey Summary

7 surveys on file from MN DNR Fisheries. Most recent: 2023-08-08 (Targeted Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
GOS27.040.05 lb
CNM19.02
Green Sunfish16.75
BCS14.03
Tullibee (Cisco)14.030.61 lb
Black Bullhead10.870.15 lb

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.

GOS

2 fish · 55 in · 2022-05-31
2105

Tullibee (Cisco)

140 fish · 216 in · 2022-05-31
36180246810121416

Black Bullhead

4 fish · 46 in · 2022-05-31
210456

From the 2023-08-08 survey

A targeted survey of nearshore fish species in Spearhead Lake was conducted on August 8-9, 2023, by Index of Biological Integrity (IBI) Program staff. Sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where possible. Backpack…

Source: MN DNR LakeFinder Fisheries Lake Survey

DNR Reports & Resources

Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Spearhead Lake. 1 report on file.

These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).

Based on 6 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Declining-0.174 m/yr6
See year-by-year chart →

Ice Season

Historical ice data from Minnesota DNR (7 observations).

Typical Ice-Out
Apr 15
Typical Ice-In
Nov 24

Estimated open water season: 223 days

EarliestLatest
Ice-Out2005-04-09 (2005)2022-05-07 (2022)
Ice-In2002-11-15 (2002)2021-12-08 (2021)

Most recent ice-out: 2022-05-07

Graded lakes near Spearhead Lake

Spearhead Lake has no grade, but these lakes within a short drive do.

Nearby Lakes in Hubbard County

Frequently asked questions about Spearhead Lake

What is the water quality grade for Spearhead Lake?

Spearhead Lake in Hubbard County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 15 ft visibility. Maximum depth: 81 ft. Surface area: 194.36 acres.

Is Spearhead Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Spearhead Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.

What is the water temperature of Spearhead Lake?

Spearhead Lake typically sits around 56°F at the surface in August, from 179 EPA Water Quality Portal field readings (2022–2025). That is a typical value for the month, not a live reading.

How deep is Spearhead Lake?

Spearhead Lake has a maximum depth of 81 feet. The lake covers 194.36 acres.

What fish are in Spearhead Lake?

Fish species found in Spearhead Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, green sunfish, hybrid sunfish, largemouth bass, northern pike, northern sunfish, pumpkinseed, rock bass, tullibee (cisco), walleye, white sucker, yellow bullhead, yellow perch. Spearhead Lake is located in Hubbard County, Minnesota.

When does Spearhead Lake thaw?

Spearhead Lake typically has ice-out around Apr 15. Ice typically forms around Nov 24. The open water season is approximately 223 days.

Where this data comes from

110 measurements from 3 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 WaterMNPCA109 samples · 2020–2025
  • Minnesota Department of Agriculture - Pesticide MonitoringMNDA_PESTICIDE1 sample · 2022

Analytical methods

  • Field measurement/observation, generic method
Monitoring station identifiers (3)

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

Lake size & watershed from HydroLAKES (HydroSHEDS)

Lake details from Minnesota DNR LakeFinder

Ice data from Minnesota DNR Climate