Magnor Lake
Magnor Lake in Polk County, Wisconsin has a water quality grade of D (Nutrient-rich). Water clarity: 3.7 ft visibility. Phosphorus: 57.7 µg/L. Maximum depth: 26 ft. Surface area: 229 acres.
Wisconsin DNR lists Panfish as common on Magnor Lake. DNR survey details →
- Clarity
- 3.7 ft
- Max depth
- 26 ft
- Area
- 229 acres
- Type
- Eutrophic
- Trend
- ↓ Declining
- Public access
- Yes
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Magnor Lake →
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Magnor Lake is a 229-acre productive, nutrient-rich eutrophic lake in Polk County, Wisconsin with a maximum depth of 26 feet. Water quality is graded D based on 1 sampling years through 2026. Overall water quality is declining over recent sampling years. The lake supports 4 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Public access is available with 1 public boat landing. Compared to the 54 other monitored lakes in Polk County, Magnor Lake ranks #52 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-07-05. Grade methodology: LakeQuality methodology.
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Swimming Safety
Grade onlyElevated nutrients
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)
Murky, only visible to about 3.7 ft. Phosphorus level: 57.7 µg/L. Trophic State Index: 60.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.7 ft | Not graded |
| Phosphorus | 57.7 µg/L | Poor |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 60 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Magnor Lake
Compare lakeside cabins, hotels, and vacation rentals near Magnor Lake in Polk County, Wisconsin — 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 Magnor Lake are listed below.
Top-rated places to stay near Magnor Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Wisconsin’s top lakes →
Wisconsin DNR lists Panfish as common on Magnor Lake.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Magnor Lake D from EPA Water Quality Portal chemistry, and the water-quality trend over 5 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 2000. 2 stations on file (most recent sample 2025).
Fish Species (DNR-rated)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 26 ft |
| Surface Area | 229 acres |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Magnor LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Magnor 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: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.25 m/yr | 5 |
| Phosphorus | ↓ Declining | +10.27 µg/L/yr | 4 |
EPA Impairment Status
Magnor Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5R).
Causes of impairment
Source: EPA ATTAINS assessment unit WI10005066 · Official waterbody report
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Magnor Lake under Clean Water Act (NPDES) discharge permits. 2 facilities have a reported Clean Water Act violation in the past three years.
- Turtle Lake Village OfTurtle Lake · 1.1 mi away · NPDES WI0025631Recent violation
- Clayton Village OfClayton · 2.8 mi away · NPDES WI0036706Recent 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 #52 of 55 lakes in Polk County
Nearby Lakes With Higher Grades
Magnor Lake holds Grade D. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Polk County
Frequently asked questions about Magnor Lake
Where is Magnor Lake?
- Magnor Lake is a lake in Polk County, Wisconsin. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Magnor Lake?
- Magnor Lake in Polk County, Wisconsin has a water quality grade of D (Nutrient-rich). Water clarity: 3.7 ft visibility. Phosphorus: 57.7 µg/L. Maximum depth: 26 ft. Surface area: 229 acres.
Is Magnor 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. Magnor Lake has a water quality grade of D (Nutrient-rich). Always check local health department advisories before swimming.
How deep is Magnor Lake?
- Magnor Lake has a maximum depth of 26 feet. The lake covers 229 acres.
What fish are in Magnor Lake?
- Fish species found in Magnor Lake include Panfish, Largemouth Bass, Northern Pike, Walleye. Magnor Lake is located in Polk County, Wisconsin.
What did the DNR fisheries survey find at Magnor Lake?
- Wisconsin DNR lists Panfish as common on Magnor Lake. A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Magnor Lake D from EPA Water Quality Portal chemistry, and the water-quality trend over 5 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Magnor Lake?
- Magnor Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Magnor Lake. Public access is listed as yes.
Explore Magnor Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
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Fish species and best lakes in Polk County
Species activity outlook by water temperature and season
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High nutrients, frequent algae, reduced clarity
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Other Grade D Lakes in Wisconsin
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Where this data comes from
26 measurements from 1 monitoring station, 2022–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX26 samples · 2022–2026
Analytical methods
- Phosphorus by Colorimetry
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)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Fish and recreation data from Wisconsin DNR Lakes
Named boat-access points from the USGS National Boat Ramps inventory