Alimagnet Lake
Alimagnet Lake in Dakota County, Minnesota has a water quality grade of F (Algae-prone). Water clarity: 5 ft visibility. Phosphorus: 71 µg/L. Chlorophyll-a (algae): 58 µg/L. Maximum depth: 11.5 ft. Surface area: 103.59 acres.
- Clarity
- 5 ft
- Typical in August
- 77°F
- Max depth
- 11.5 ft
- Area
- 104 acres
- Type
- Eutrophic
- Trend
- → Stable
- Public access
- No
- Ice-out
- Apr 5
- Open water
- 231 days
Grade F measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Alimagnet Lake →
Next lake in Dakota County
Alimagnet Lake is a 104-acre productive, nutrient-rich eutrophic lake in Dakota County, Minnesota with a maximum depth of 12 feet. Water quality is graded F based on 2 sampling years through 2025. Limited fish-species data available. No public access — the lake is private or restricted. Compared to the 44 other monitored lakes in Dakota County, Alimagnet Lake ranks #43 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-19. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyLimited data
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.
Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom
Water Quality Grade: F (Algae-prone)
Murky, only visible to about 5 ft. Phosphorus level: 71 µg/L. Chlorophyll-a: 58 µg/L. Trophic State Index: 63.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 5 ft | Not graded |
| Phosphorus | 71 µg/L | Poor |
| Chlorophyll-a (Algae) | 58 µg/L | Poor |
| Trophic State Index (TSI) | 63 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Alimagnet Lake
Compare lakeside cabins, hotels, and vacation rentals near Alimagnet Lake in Dakota 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Alimagnet Lake are listed below.
Top-rated places to stay near Alimagnet Lake
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
Alimagnet Lake typically sits around 77°F at the surface in August. Summer average is about 78°F. Usually warmest in Jul (about 84°F) and coldest in Apr (about 47°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 45 field readings (2010–2025) via the EPA Water Quality Portal. See the full Alimagnet Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 11.5 ft |
| Surface Area | 104 acres |
| Shoreline Length | 3.4 mi |
| Littoral Zone | 100% |
| Public Access | No |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fishing Alimagnet 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: → Stable
Based on 2 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | -0.02 m/yr | 2 |
Ice Season
Historical ice data from Minnesota DNR (70 observations).
Estimated open water season: 231 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2000-03-08 (2000) | 1975-04-26 (1975) |
| Ice-In | 1991-11-01 (1991) | 1998-12-21 (1998) |
Most recent ice-out: 2008-04-20
EPA Impairment Status
Alimagnet Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN19-0021-00 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Alimagnet Lake under Clean Water Act (NPDES) discharge permits.
- Minnegasco Energy Dist SystemBurnsville · 2.5 mi away · NPDES MN0063649
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 #43 of 45 lakes in Dakota County
Nearby Lakes With Higher Grades
Alimagnet Lake holds Grade F. 3 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
Nearby Lakes in Dakota County
Frequently asked questions about Alimagnet Lake
What is the water quality grade for Alimagnet Lake?
- Alimagnet Lake in Dakota County, Minnesota has a water quality grade of F (Algae-prone). Water clarity: 5 ft visibility. Phosphorus: 71 µg/L. Chlorophyll-a (algae): 58 µg/L. Maximum depth: 11.5 ft. Surface area: 103.59 acres.
Is Alimagnet Lake safe to swim in?
- Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom. Alimagnet Lake has a water quality grade of F (Algae-prone). Algae concentration (chlorophyll-a) is 58 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Alimagnet Lake?
- Alimagnet Lake typically sits around 77°F at the surface in August, from 45 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Alimagnet Lake?
- Alimagnet Lake has a maximum depth of 11.5 feet. The lake covers 103.59 acres.
When does Alimagnet Lake thaw?
- Alimagnet Lake typically has ice-out around Apr 5. Ice typically forms around Nov 22. The open water season is approximately 231 days.
Explore Alimagnet Lake across LakeGrade
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Where this data comes from
56 measurements from 2 monitoring stations, 2024–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA56 samples · 2024–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- Analysis of Chlorophyll in Periphyton and Plankton
Monitoring station identifiers (2)
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
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