Bug Lake
Bug Lake in Forest County, Wisconsin has a water quality grade of A (Excellent). Phosphorus: 9.5 µg/L. Chlorophyll-a (algae): 1 µg/L.
- Typical in August
- 54°F
- Type
- Oligotrophic
- Trend
- → Stable
- Public access
- Yes
Next lake in Forest County
Bug Lake is a cold, clear oligotrophic lake in Forest County, Wisconsin. Water quality is graded A based on 2 sampling years through 2025. Phosphorus level is declining over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 22 other monitored lakes in Forest County, Bug Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-11-19. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyBacteria A
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.
Based on E. coli testing, Bug Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 12 samples across 5 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Wisconsin’s current beach and health-department advisories before swimming.
Water Quality Grade: A (Excellent)
No clarity data. Phosphorus level: 9.5 µg/L. Chlorophyll-a: 1 µg/L. Trophic State Index: 34.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 9.5 µg/L | Good |
| Chlorophyll-a (Algae) | 1 µg/L | Good |
| Trophic State Index (TSI) | 34 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Bug Lake
Compare lakeside cabins, hotels, and vacation rentals near Bug Lake in Forest 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 Bug Lake
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Water Temperature
Bug Lake typically sits around 54°F at the surface in August. Summer average is about 52°F. Usually warmest in Aug (about 54°F) and coldest in Nov (about 41°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 160 field readings (2024–2025) via the EPA Water Quality Portal. See the full Bug Lake water temperature breakdown →
Recreation & Access
- Wabikon LakePublic
Fishing Bug Lake
Water Quality Trend: → Stable
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Phosphorus | ↓ Declining | +0.49 µg/L/yr | 6 |
| Chlorophyll-a | ↑ Improving | -0.15 µg/L/yr | 6 |
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Bug Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Crandon Recirculating Sand Filter/Stone Lake WwtpCrandon · 1.5 mi away · NPDES WI0058424Recent 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 #2 of 23 lakes in Forest County
Nearby Lakes in Forest County
Frequently asked questions about Bug Lake
What is the water quality grade for Bug Lake?
- Bug Lake in Forest County, Wisconsin has a water quality grade of A (Excellent). Phosphorus: 9.5 µg/L. Chlorophyll-a (algae): 1 µg/L.
Is Bug Lake safe to swim in?
- Based on E. coli testing, Bug Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 12 samples across 5 seasons. That works out to a bacteria swim-safety grade of A — a historical summary of past testing, not a current reading. Bug Lake has a water quality grade of A (Excellent). Bacteria levels can spike quickly after heavy rain, so always check Wisconsin's current beach and health-department advisories before you swim.
What is the water temperature of Bug Lake?
- Bug Lake typically sits around 54°F at the surface in August, from 160 EPA Water Quality Portal field readings (2024–2025). That is a typical value for the month, not a live reading.
Are there boat ramps on Bug Lake?
- Bug Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Wabikon Lake. Public access is listed as yes.
Explore Bug Lake across LakeGrade
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Where this data comes from
84 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Forest County Potawatomi Community (Tribal)
FCPOTAWATOMI_WQX84 samples · 2020–2025
Analytical methods
- 4500 P E ~ Phosphorus in Water by Colorimetry- Ascorbic Acid Method
- 4500 P F ~ Phosphorus in Water by Colorimetry Automated Ascorbic Acid Method
- 10200 H ~ Chlorophyll a-b-c Determination
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Named boat-access points from the USGS National Boat Ramps inventory