Long Lake
Long Lake in Polk County, Wisconsin has a water quality grade of C (Fair). Water clarity: 5 ft visibility. Phosphorus: 27.7 µg/L. Maximum depth: 44 ft. Surface area: 61 acres.
Wisconsin DNR lists Panfish as present on Long Lake. DNR survey details →
- Clarity
- 5 ft
- Max depth
- 44 ft
- Area
- 61 acres
- Type
- Eutrophic
- Public access
- Yes
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Long Lake is a 61-acre productive, nutrient-rich eutrophic lake in Polk County, Wisconsin with a maximum depth of 44 feet. Water quality is graded C based on 1 sampling years through 2020. The lake supports 3 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, Long Lake ranks #27 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2020-08-31. Grade methodology: LakeQuality 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.
Generally safe for swimming, moderate water quality
Water Quality Grade: C (Fair)
Murky, only visible to about 5 ft. Phosphorus level: 27.7 µg/L. Trophic State Index: 53.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 5 ft | Not graded |
| Phosphorus | 27.7 µg/L | Fair |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 53 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Long Lake
Compare lakeside cabins, hotels, and vacation rentals near Long 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.
Top-rated places to stay near Long Lake
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Planning a whole trip? See where to stay at Wisconsin’s top lakes →
Wisconsin DNR lists Panfish as present on Long Lake.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Long Lake C from EPA Water Quality Portal chemistry. 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. 1 station on file (most recent sample 2020).
Fish Species (DNR-rated)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 44 ft |
| Surface Area | 61 acres |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Long 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 Long 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.
EPA Impairment Status
Long 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 WI10005054 · Official waterbody report
County Ranking
Ranked #27 of 55 lakes in Polk County
Nearby Lakes With Higher Grades
Long Lake holds Grade C. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
Nearby Lakes in Polk County
Frequently asked questions about Long Lake
Where is Long Lake?
- Long Lake is a lake in Polk County, Wisconsin. LakeQuality grades it C for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Long Lake?
- Long Lake in Polk County, Wisconsin has a water quality grade of C (Fair). Water clarity: 5 ft visibility. Phosphorus: 27.7 µg/L. Maximum depth: 44 ft. Surface area: 61 acres.
Is Long Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Long Lake has a water quality grade of C (Fair). Always check local health department advisories before swimming.
How deep is Long Lake?
- Long Lake has a maximum depth of 44 feet. The lake covers 61 acres.
What fish are in Long Lake?
- Fish species found in Long Lake include Panfish, Largemouth Bass, Northern Pike. Long Lake is located in Polk County, Wisconsin.
What did the DNR fisheries survey find at Long Lake?
- Wisconsin DNR lists Panfish as present on Long Lake. A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Long Lake C from EPA Water Quality Portal chemistry. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Long Lake?
- Long Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Long Lake. Public access is listed as yes.
Explore Long Lake across LakeQuality
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Species activity outlook by water temperature and season
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High nutrients, frequent algae, reduced clarity
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State Parks Near Long Lake
Other Grade C Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
Where this data comes from
6 measurements from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX6 samples · 2020
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
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