Sugar Lake
Sugar Lake in Aitkin County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 14.5 ft visibility. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 3.2 µg/L. Maximum depth: 45 ft. Surface area: 415.87 acres.
- Clarity
- 14.5 ft
- Typical in August
- 67°F
- Max depth
- 45 ft
- Area
- 416 acres
- Trend
- → Stable
- Public access
- Yes
- Ice-out
- Apr 16
- Open water
- 229 days
Next lake in Aitkin County
Why Sugar 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 Sugar 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, 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.
Sugar Lake is a 416-acre lake in Aitkin County, Minnesota with a maximum depth of 45 feet. The lake supports 13 documented fish species including black crappie, bluegill, and brown bullhead. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-17. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Sugar Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 14.5 ft. Phosphorus level: 10 µg/L. Chlorophyll-a: 3.2 µg/L. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 14.5 ft | Not graded |
| Phosphorus | 10 µg/L | Not graded |
| Chlorophyll-a (Algae) | 3.2 µg/L | Not graded |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Sugar Lake
Compare lakeside cabins, hotels, and vacation rentals near Sugar Lake in Aitkin 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 Sugar Lake
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Water Temperature
Sugar Lake typically sits around 67°F at the surface in August. Summer average is about 64°F. Usually warmest in Jul (about 67°F) and coldest in May (about 54°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 138 field readings (2016–2025) via the EPA Water Quality Portal. See the full Sugar Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 45 ft |
| Surface Area | 416 acres |
| Shoreline Length | 4.1 mi |
| Littoral Zone | 64% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Sugar LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Sugar Lake
DNR Fisheries Survey Summary
13 surveys on file from MN DNR Fisheries. Most recent: 2024-08-06 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluegill | 13.35 | 0.14 lb |
| Bluntnose Minnow | 11.80 | — |
| Yellow Bass | 8.04 | 0.49 lb |
| CNM | 5.24 | — |
| MTS | 5.24 | — |
| Northern Pike | 5.11 | 1.53 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.
Bluegill
Yellow Bass
Northern Pike
From the 2024-08-06 survey
Sugar Lake is a 398-acre lake located east of Glen, in south central Aitkin County, and has a state-owned public access on the south shore. About 60 percent of the lake is less than 15 feet deep, with a 25-foot basin in the east end of the lake and a 45-foot basin in the south-central part of the lake. The water is…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Sugar Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — SugarFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Sugar (0017)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — SugarFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — SugarPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: → Stable
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.038 m/yr | 5 |
Ice Season
Historical ice data from Minnesota DNR (13 observations).
Estimated open water season: 229 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2005-04-10 (2005) | 2013-05-11 (2013) |
| Ice-In | 2003-11-25 (2003) | 2001-12-20 (2001) |
Most recent ice-out: 2015-04-11
EPA Impairment Status
Sugar Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MN01-0087-00 · Official waterbody report
Graded lakes near Sugar Lake
Sugar Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Aitkin County
Frequently asked questions about Sugar Lake
What is the water quality grade for Sugar Lake?
- Sugar Lake in Aitkin County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 14.5 ft visibility. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 3.2 µg/L. Maximum depth: 45 ft. Surface area: 415.87 acres.
Is Sugar Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Sugar Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Algae concentration (chlorophyll-a) is 3.2 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Sugar Lake?
- Sugar Lake typically sits around 67°F at the surface in August, from 138 EPA Water Quality Portal field readings (2016–2025). That is a typical value for the month, not a live reading.
How deep is Sugar Lake?
- Sugar Lake has a maximum depth of 45 feet. The lake covers 415.87 acres.
What fish are in Sugar Lake?
- Fish species found in Sugar Lake include black crappie, bluegill, brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, smallmouth bass, walleye, white sucker, yellow bullhead, yellow perch. Sugar Lake is located in Aitkin County, Minnesota.
When does Sugar Lake thaw?
- Sugar Lake typically has ice-out around Apr 16. Ice typically forms around Dec 1. The open water season is approximately 229 days.
Are there boat ramps on Sugar Lake?
- Sugar Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Sugar Lake. Public access is listed as yes.
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Where this data comes from
28 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
MNPCA28 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- 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)
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
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate