Round Lake is a 308-acre mesotrophic lake in McHenry County, North Dakota with a maximum depth of 17 feet (12-foot average). Water quality is graded A based on 2 sampling years through 2021. The lake supports 4 documented fish species including Yellow Perch, Northern Pike, and Black Bullhead. Public access is available. Compared to the 2 other monitored lakes in McHenry County, Round Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, North Dakota DNR, last sampled 2021-10-12. Grade methodology: LakeGrade methodology.
Watch Round Lake water quality
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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 12.1 ft. Chlorophyll-a: 2.4 µg/L. Trophic State Index: 40.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 12.1 ft | B |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 2.4 µg/L | A |
| Trophic State Index (TSI) | 40 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 16.7 ft |
| Average Depth | 11.7 ft |
| Surface Area | 308 acres |
| Shoreline Length | 5.2 mi |
| Public Access | Yes |
Where to stay near Round Lake
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Fish Species
Click a species to see every graded lake where it is documented.
Fishing Round Lake
Water Temperature
Round Lake averages about 60°F at the surface in summer, usually warmest in Aug (about 64°F) and coldest in May (about 47°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 13 field readings (2010–2021) via the EPA Water Quality Portal. See the full Round Lake water temperature breakdown →
Location
County Ranking
Ranked #1 of 3 lakes in McHenry County
Nearby Lakes in McHenry County
Explore Round Lake across LakeGrade
Fish species and top-graded lakes across North Dakota
Fish species and best lakes in McHenry County
Species activity outlook by water temperature and season
Where to stay at North Dakota's top lakes, each with its grade
Moderate nutrients, good water quality
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Other Grade A Lakes in North Dakota
Mesotrophic Lakes in North Dakota
More records, surveys & data sources
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth is a modeled estimate.
Data Sources
Water quality data from the EPA Water Quality Portal
Lake size & watershed from HydroLAKES (HydroSHEDS)
Grading methodology based on Metropolitan Council standards
Depth, fish, and access data from North Dakota Game & Fish
Most recent sample: 2021-10-12
Monitoring stations: 1