Round Lake
Lake County, WisconsinMesotrophic
Round Lake is a 242-acre mesotrophic lake in Lake County, IL. Water quality is graded B based on 2 sampling years through 2022. Compared to the 15 other monitored lakes in Lake County, Round Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2022-10-12. Grade methodology: LakeGrade methodology.
Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Moderate clarity, visible to about 7.4 ft. Phosphorus level: 19.5 µg/L. Trophic State Index: 48.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 7.4 ft | C |
| Phosphorus | 19.5 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 48 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 242 acres |
Location
County Ranking
Ranked #4 of 16 lakes in Lake County
Nearby Lakes in Lake County
More Wisconsin Lake Rankings
Other Grade B Lakes in Wisconsin
Mesotrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Round Lake is a man-made reservoir impounded by the Round Lake Dam (completed 1945), built primarily for recreation on the TRIB SQUAW CREEK; earth-type dam, 9 ft tall and 140 ft long.
- Surface area
- 242 ac
- Normal storage
- 976 ac-ft
- Max storage
- 1,484 ac-ft
- Drainage area
- 2.5 sq mi
- Hazard class
- Significant
- Owner
- VILLAGE OF ROUND LAKE BEACH
Source: USACE National Inventory of Dams, NID ID IL00593 · Operator website
EPA Impairment Status
Round 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 IL_RTZP · Official waterbody report · Matched by proximity (1.29 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: 2022-10-12
Monitoring stations: 3