Long Lake
Long Lake in Oneida County, Wisconsin is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 10.5 ft visibility. Maximum depth: 58 ft. Surface area: 113 acres.
Wisconsin DNR lists Panfish as common on Long Lake. DNR survey details →
- Clarity
- 10.5 ft
- Max depth
- 58 ft
- Area
- 113 acres
- Trend
- → Stable
- Public access
- Yes
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Why Long Lake has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Long Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by WI DNR and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Long Lake is a 113-acre lake in Oneida County, Wisconsin with a maximum depth of 58 feet. Water clarity is improving over recent sampling years. The lake supports 4 documented fish species including Musky, Panfish, and Largemouth Bass. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2023-08-06. Grade methodology: LakeQuality methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Long Lake
These readings exist but are not enough for an A–F grade — see why.
Good clarity, visible to about 10.5 ft. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10.5 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Long Lake
Compare lakeside cabins, hotels, and vacation rentals near Long Lake in Oneida 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 common on Long Lake.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality does not assign an A–F grade on Long Lake — official chemistry is on file, not a letter, and the water-quality trend over 6 years of monitoring is stable. 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. 2 stations on file (most recent sample 2023).
Fish Species (DNR-rated)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 58 ft |
| Surface Area | 113 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
Water Quality Trend: → Stable
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.946 m/yr | 6 |
| Phosphorus | ↓ Declining | +0.84 µg/L/yr | 6 |
EPA Impairment Status
Long Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit WI10007346 · Official waterbody report
Graded lakes near Long Lake
Long Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Oneida County
Frequently asked questions about Long Lake
Where is Long Lake?
- Long Lake is a lake in Oneida County, Wisconsin. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Long Lake?
- Long Lake in Oneida County, Wisconsin is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 10.5 ft visibility. Maximum depth: 58 ft. Surface area: 113 acres.
Is Long Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Long Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is Long Lake?
- Long Lake has a maximum depth of 58 feet. The lake covers 113 acres.
What fish are in Long Lake?
- Fish species found in Long Lake include Musky, Panfish, Largemouth Bass, Walleye. Long Lake is located in Oneida County, Wisconsin.
What did the DNR fisheries survey find at Long Lake?
- Wisconsin DNR lists Panfish as common on Long Lake. A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality does not assign an A–F grade on Long Lake — official chemistry is on file, not a letter, and the water-quality trend over 6 years of monitoring is stable. 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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Where this data comes from
12 measurements from 1 monitoring station, 2020–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX12 samples · 2020–2023
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