Aaron Lake
Douglas County, Minnesota610 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Aaron Lake. Here is what has been measured.
- Impaired · Mercury
- zebra mussel
- 16 ft max depth
- Public access
- Limited data
Aaron Lake in Douglas County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7 ft visibility. Maximum depth: 16 ft. Surface area: 610.3 acres.
Minnesota DNR's Targeted Survey on May 14, 2024 caught 3.62 black crappie per trap net at Aaron Lake. DNR survey details →
Aaron Lake is a 610-acre lake in Douglas County, Minnesota with a maximum depth of 16 feet (9-foot average). Overall water quality is declining over recent sampling years. The lake supports 15 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-22. Methodology: how these readings are compared.
What Aaron Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing15 species recorded
- Ice seasonIce-out around Apr 25
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Aaron Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Aaron 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 Aaron Lake
These are the measurements Minnesota PCA publishes for Aaron Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 7 ft. TSI 49.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7ft | 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. | 49 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Aaron Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Aaron Lake typically sits around 70°F at the surface in September. Summer average is about 76°F. Usually warmest in Jul (about 78°F) and coldest in May (about 60°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (60°F) to its warmest (78°F).
Typical surface water temperature by month, from 14 field readings (2022–2025) via the EPA Water Quality Portal. See the full Aaron Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on May 14, 2024 caught 3.62 black crappie per trap net at Aaron Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Aaron Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
13 surveys on file from MN DNR Fisheries. Most recent: 2024-05-14 (Targeted Survey).
13 surveys on file · most recent 2024-05-14 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Golden Shiner | 97.86 | ||
| Yellow Perch | 97.70 | 5–9 in 2022-06-27 | 0.14 lb |
| Spottail Shiner | 35.13 | ||
| Bluegill | 34.12 | 3–8 in 2024-05-14 | 0.16 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.
Yellow Perch
Bluegill
From the 2024-05-14 survey
A targeted survey was conducted May 14-15 on Aaron Lake to assess the Bluegill and Black Crappie populations. Bluegill were abundant (90.5/trap net). Lengths ranged from 3.4 to 8.9 inches, with an average of 6.8 inches. Growth is below average for the area, but Bluegill were recorded out to age 12. Black Crappie catch…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Aaron Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — AaronFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — AaronFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — AaronPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
16 ft
Average depth
9 ft
Surface area
610 acres
Shoreline
4.9 mi
Littoral zone
77%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
7 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,348 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Lake AaronPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Aaron Lake
Compare lakeside cabins, hotels, and vacation rentals near Aaron Lake in Douglas 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 Aaron Lake
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Fish Species
Click a species to see every lake where it is documented.
Fishing Aaron Lake
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Ice season
Typical ice-out
Apr 25
Earliest Mar 7, 2024 · Latest Apr 30, 2008
Typical ice-in
Nov 22
Earliest Nov 18, 2022 · Latest Dec 7, 2021
Most recent ice-out
Apr 7
2025
11 observations · Minnesota PCA ice records
Reservoir Info (USACE NID)
Aaron Lake is a man-made reservoir impounded by the Lake Aaron (completed 1964), built primarily for recreation on the Chippewa River-TR; gravity-type dam, 8 ft tall and 10 ft long.
- Surface area
- 611 ac
- Normal storage
- 178,500 ac-ft
- Max storage
- 190,000 ac-ft
- Drainage area
- 6.5 sq mi
- Hazard class
- Low
- Owner
- MNDNR
Source: USACE National Inventory of Dams, NID ID MN00173 · Operator website
EPA Impairment Status
Aaron Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption.
Source: EPA ATTAINS assessment unit MN21-0242-00 · Official waterbody report
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Aaron Lake under Clean Water Act (NPDES) discharge permits.
- Millerville WwtpMillerville · 1.8 mi away · NPDES MN0054305
- Joe Wagner FarmBrandon · 2.7 mi away · NPDES MN0070866
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.
Nearby Lakes in Douglas County
Frequently asked questions about Aaron Lake
Where is Aaron Lake?
- Aaron Lake is a lake in Douglas County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Aaron Lake?
- Aaron Lake in Douglas County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7 ft visibility. Maximum depth: 16 ft. Surface area: 610.3 acres.
Is Aaron Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Aaron Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
What is the water temperature of Aaron Lake?
- Aaron Lake typically sits around 70°F at the surface in September, from 14 EPA Water Quality Portal field readings (2022–2025). That is a typical value for the month, not a live reading.
How deep is Aaron Lake?
- Aaron Lake has a maximum depth of 16 feet and an average depth of 9 feet. The lake covers 610.3 acres.
What fish are in Aaron Lake?
- Fish species found in Aaron Lake include black bullhead, black crappie, bluegill, brown bullhead, common carp, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, smallmouth bass, walleye, white sucker, yellow bullhead, yellow perch. Aaron Lake is located in Douglas County, Minnesota.
What did the DNR fisheries survey find at Aaron Lake?
- Minnesota DNR's Targeted Survey on May 14, 2024 caught 3.62 black crappie per trap net at Aaron Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Aaron Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Aaron Lake thaw?
- Aaron Lake typically has ice-out around Apr 25. Ice typically forms around Nov 22. The open water season is approximately 211 days.
Are there boat ramps on Aaron Lake?
- Aaron Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Aaron. Public access is listed as yes.
Can I fish at Aaron Lake?
- Aaron Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. 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 Aaron Lake across LakeQuality
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Where this data comes from
39 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
MNPCA39 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
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