Muewissen Lake
Muewissen Lake in Carver County, Minnesota has a water quality grade of D (Nutrient-rich). Water clarity: 1.8 ft visibility. Phosphorus: 98.5 µg/L. Chlorophyll-a (algae): 18.7 µg/L.
- Clarity
- 1.8 ft
- Typical in August
- 72°F
- Type
- Eutrophic
- Trend
- ↑ Improving
- Public access
- No
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Muewissen Lake →
Next lake in Carver County
Muewissen Lake is a productive, nutrient-rich eutrophic lake in Carver County, Minnesota. Water quality is graded D based on 2 sampling years through 2025. Overall water quality is improving over recent sampling years. Limited fish-species data available. No public access — the lake is private or restricted. Compared to the 37 other monitored lakes in Carver County, Muewissen Lake ranks #16 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-07. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyAlgae risk
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.
Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum
Water Quality Grade: D (Nutrient-rich)
Very murky, less than 1.8 ft of visibility. Phosphorus level: 98.5 µg/L. Chlorophyll-a: 18.7 µg/L. Trophic State Index: 66.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.8 ft | Not graded |
| Phosphorus | 98.5 µg/L | Poor |
| Chlorophyll-a (Algae) | 18.7 µg/L | Poor |
| Trophic State Index (TSI) | 66 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Muewissen Lake
Compare lakeside cabins, hotels, and vacation rentals near Muewissen Lake in Carver 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 Muewissen Lake are listed below.
Top-rated places to stay near Muewissen Lake
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
Muewissen Lake typically sits around 72°F at the surface in August. Summer average is about 74°F. Usually warmest in Jul (about 75°F) and coldest in Feb (about 32°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 86 field readings (2019–2025) via the EPA Water Quality Portal. See the full Muewissen Lake water temperature breakdown →
Fishing Muewissen Lake
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.041 m/yr | 6 |
| Phosphorus | ↑ Improving | -32.53 µg/L/yr | 6 |
| Chlorophyll-a | ↑ Improving | -18.68 µg/L/yr | 6 |
EPA Impairment Status
Muewissen 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 MN10-0069-00 · Official waterbody report · Matched by proximity (0.96 km)
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Muewissen Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Cologne WwtpCologne · 0.2 mi away · NPDES MN0023108Recent violation
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 #16 of 38 lakes in Carver County
Nearby Lakes in Carver County
Frequently asked questions about Muewissen Lake
What is the water quality grade for Muewissen Lake?
- Muewissen Lake in Carver County, Minnesota has a water quality grade of D (Nutrient-rich). Water clarity: 1.8 ft visibility. Phosphorus: 98.5 µg/L. Chlorophyll-a (algae): 18.7 µg/L.
Is Muewissen Lake safe to swim in?
- Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. Muewissen Lake has a water quality grade of D (Nutrient-rich). Algae concentration (chlorophyll-a) is 18.7 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Muewissen Lake?
- Muewissen Lake typically sits around 72°F at the surface in August, from 86 EPA Water Quality Portal field readings (2019–2025). That is a typical value for the month, not a live reading.
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Where this data comes from
129 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
MNPCA129 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent 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
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)