Round Lake
Shawano County, WisconsinMesotrophic
On the LakeGrade rubric, Round Lake pulls an A: clarity at 11.0 ft and 15 µg/L of phosphorus put it in the top bracket for Wisconsin. clarity and phosphorus rate similarly, so there is no obvious single lever to pull on watershed management.
Mesotrophic conditions dominate at Round Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. A maximum depth of 39 ft puts Round Lake in the middle of Wisconsin's depth distribution. The lake is compact at 27 acres, with partial shoreline records and little volume to buffer nutrient inputs. Within Shawano County's 27 graded waters, Round Lake sits at rank 2, near the top of the local distribution.
Eurasian watermilfoil has been documented at Round Lake, requiring shoreline management to keep dense mats from crowding native vegetation. Walleye are documented at Round Lake, one of 5 fish species on record for the lake. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-10-24. Grade methodology: LakeGrade methodology.
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Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Good clarity, visible to about 11 ft. Phosphorus level: 14.8 µg/L. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 11 ft | B |
| Phosphorus | 14.8 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 39 ft |
| Surface Area | 27 acres |
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Round Lake (14-day solunar calendar)
→ Is it safe to eat fish from Round Lake? (mercury & PFAS guide)
→ Round Lake fishing regulations (limits, seasons, special rules)
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 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.429 m/yr | 6 |
| Phosphorus | → Stable | -0.26 µg/L/yr | 6 |
Location
County Ranking
Ranked #2 of 27 lakes in Shawano County
Nearby Lakes in Shawano County
More Wisconsin Lake Rankings
Other Grade A Lakes in Wisconsin
Washington County · Clarity: 11.8 ft
Washington County · Clarity: 12.6 ft
Walworth County · Clarity: 11 ft
Waukesha County · Clarity: 11.3 ft
Walworth County · Clarity: 20.2 ft
Kenosha County · Clarity: 10 ft
Mesotrophic Lakes in Wisconsin
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1987. 1 station on file (most recent sample 2025).
Fish Species (DNR-rated)
EPA Impairment Status
Round Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit WI10000097 · Official waterbody report · Matched by proximity (2.81 km)
Data Sources
Water quality data from the EPA Water Quality Portal
Impairment status from EPA ATTAINS 303(d) database
Grading methodology based on Metropolitan Council standards
Most recent sample: 2025-10-24
Monitoring stations: 1