Franklin Lake
Franklin Lake in Oneida County, Wisconsin has a water quality grade of B (Good). Water clarity: 16.2 ft visibility. Phosphorus: 12.3 µg/L. Maximum depth: 25 ft. Surface area: 159 acres.
Wisconsin DNR lists Musky as present on Franklin Lake. DNR survey details →
- Clarity
- 16.2 ft
- Typical in August
- 72°F
- Max depth
- 25 ft
- Area
- 159 acres
- Type
- Oligotrophic
- Trend
- ↑ Improving
Next lake in Oneida County
Swipe left or right on this bar to open the next or previous lake.
Franklin Lake is a 159-acre cold, clear oligotrophic lake in Oneida County, Wisconsin with a maximum depth of 25 feet. Water quality is graded B based on 1 sampling years through 2026. Overall water quality is improving over recent sampling years. The lake supports 5 documented fish species including Musky, Panfish, and Largemouth Bass. Compared to the 66 other monitored lakes in Oneida County, Franklin Lake ranks #18 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-06-30. Grade methodology: LakeQuality methodology.
Watch Franklin Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Grade onlyLow algae
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.
Good for swimming, clear water with low algae levels
Water Quality Grade: B (Good)
Crystal clear, you can see 16.2 ft down. Phosphorus level: 12.3 µg/L. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 16.2 ft | Not graded |
| Phosphorus | 12.3 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Franklin Lake
Compare lakeside cabins, hotels, and vacation rentals near Franklin 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 Franklin 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 →
Water Temperature
Franklin Lake typically sits around 72°F at the surface in August. Summer average is about 72°F. Usually warmest in Jul (about 74°F) and coldest in Apr (about 46°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 78 field readings (2024–2026) via the EPA Water Quality Portal. See the full Franklin Lake water temperature breakdown →
Wisconsin DNR lists Musky as present on Franklin Lake.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Franklin Lake B from EPA Water Quality Portal chemistry, and the water-quality trend over 7 years of monitoring is improving. 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 2001. 1 station on file (most recent sample 2026).
Fish Species (DNR-rated)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 25 ft |
| Surface Area | 159 acres |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Franklin Lake
Water Quality Trend: ↑ Improving
Based on 7 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.326 m/yr | 5 |
| Phosphorus | ↑ Improving | -0.26 µg/L/yr | 6 |
EPA Impairment Status
Franklin 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 WI10026427 · Official waterbody report
County Ranking
Ranked #18 of 67 lakes in Oneida County
Nearby Lakes in Oneida County
Frequently asked questions about Franklin Lake
Where is Franklin Lake?
- Franklin Lake is a lake in Oneida County, Wisconsin. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Franklin Lake?
- Franklin Lake in Oneida County, Wisconsin has a water quality grade of B (Good). Water clarity: 16.2 ft visibility. Phosphorus: 12.3 µg/L. Maximum depth: 25 ft. Surface area: 159 acres.
Is Franklin Lake safe to swim in?
- Good for swimming, clear water with low algae levels. Franklin Lake has a water quality grade of B (Good). Always check local health department advisories before swimming.
What is the water temperature of Franklin Lake?
- Franklin Lake typically sits around 72°F at the surface in August, from 78 EPA Water Quality Portal field readings (2024–2026). That is a typical value for the month, not a live reading.
How deep is Franklin Lake?
- Franklin Lake has a maximum depth of 25 feet. The lake covers 159 acres.
What fish are in Franklin Lake?
- Fish species found in Franklin Lake include Musky, Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike. Franklin Lake is located in Oneida County, Wisconsin.
What did the DNR fisheries survey find at Franklin Lake?
- Wisconsin DNR lists Musky as present on Franklin Lake. A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Franklin Lake B from EPA Water Quality Portal chemistry, and the water-quality trend over 7 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Explore Franklin Lake across LakeQuality
Fish species and top-graded lakes across Wisconsin
Fish species and best lakes in Oneida County
Species activity outlook by water temperature and season
Top lakes and where to stay in the Northwoods Wisconsin area
Top lakes and where to stay in the Minocqua Chain area
Where to stay at Wisconsin's top lakes, each with its grade
Lakes in the Wisconsin River Watershed, ranked by water quality
Low nutrients, clear water, excellent for swimming
Wisconsin's cleanest and most-polluted lakes, ranked
More Wisconsin Lake Rankings
Other Grade B Lakes in Wisconsin
Oligotrophic Lakes in Wisconsin
Where this data comes from
119 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX119 samples · 2020–2026
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Fish and recreation data from Wisconsin DNR Lakes