Halfmoon Lake
Wabasha County, MinnesotaView mapDirections
Minnesota PCA publishes the water-quality measurements for Halfmoon Lake. Here is what has been measured.
- Public access
- Limited data
Halfmoon Lake in Wabasha County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.1 ft visibility.
Halfmoon Lake is a lake in Wabasha County, Minnesota. Limited fish-species data available. Public access is available.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-10-04. Methodology: how these readings are compared.
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Halfmoon 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 Halfmoon Lake
These are the measurements Minnesota PCA publishes for Halfmoon Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5.1 ft. TSI 54.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.1ft | 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. | 54 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Halfmoon Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Halfmoon Lake typically sits around 68°F at the surface in September. Summer average is about 72°F. Usually warmest in Jul (about 75°F) and coldest in Sep (about 68°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (68°F) to its warmest (75°F).
Typical surface water temperature by month, from 9 field readings (2023–2023) via the EPA Water Quality Portal. See the full Halfmoon Lake water temperature breakdown →
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Stays near Halfmoon Lake
Compare lakeside cabins, hotels, and vacation rentals near Halfmoon Lake in Wabasha 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.
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Fishing Halfmoon Lake
Regulated Pollution Sources Nearby
3 EPA-permitted facilities operate within about 5 miles of Halfmoon Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Waumandee Sanitary District #1Waumandee · 4.5 mi away · NPDES WI0061646Recent violation
- Affordable Septic StorageBuffalo City · 2.4 mi away · NPDES WI0065854
- Village Of CochraneCochrane, Village Of · 3.7 mi away · NPDES WI0020214
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 Wabasha County
Frequently asked questions about Halfmoon Lake
Where is Halfmoon Lake?
- Halfmoon Lake is a lake in Wabasha County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Halfmoon Lake?
- Halfmoon Lake in Wabasha County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.1 ft visibility.
Is Halfmoon Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Halfmoon Lake?
- Halfmoon Lake typically sits around 68°F at the surface in September, from 9 EPA Water Quality Portal field readings (2023–2023). That is a typical value for the month, not a live reading.
Can I fish at Halfmoon Lake?
- Public access to Halfmoon Lake is listed as yes on the lake record. 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.
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Where this data comes from
5 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA5 samples · 2023
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)