Round Lake
Mecosta County, Michigan157 acresView mapDirections
Clarity, phosphorus, and algae all sit in the cleanest band for this region.
↓ down from B at the last regrade
- Mesotrophic
- #2 of 6 in the county
- 45 ft max depth
Round Lake in Mecosta County, Michigan has a water quality grade of A (Excellent). Water clarity: 9 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 6.8 µg/L. Maximum depth: 45 ft. Surface area: 156.5 acres.
- Clarity
- 9 ft
- Max depth
- 45 ft
- Area
- 157 acres
- Type
- Mesotrophic
- Phosphorus
- 17 µg/L
- Chlorophyll-a
- 6.8 µg/L
- Trend
- ↓ Declining
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Watch Round Lake’s letter
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Round Lake is a 157-acre mesotrophic lake in Mecosta County, Michigan with a maximum depth of 45 feet. Water quality is graded A based on 2 sampling years through 2023. Overall water quality is declining over recent sampling years. Compared to the 5 other monitored lakes in Mecosta County, Round Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, EGLE, last sampled 2023-09-15. Grade methodology: LakeQuality methodology.
What Round Lake is good for
From access and monitoring records, not editorial picks.
- Deep water45 ft surveyed max depth
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.
The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: A (Excellent)
Moderate clarity, visible to about 9 ft. Phosphorus 17 µg/L. Chlorophyll-a 6.8 µg/L. TSI 47. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 9 ft | Not graded |
| Phosphorus | 17 µg/L | Good |
| Chlorophyll-a (Algae) | 6.8 µg/L | Good |
| Trophic State Index (TSI) | 47 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 45 ft |
| Surface Area | 157 acres |
Fishing Round Lake
Water Quality Trend: ↓ Declining
Based on 7 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.033 m/yr | 7 |
| Phosphorus | → Stable | +0.15 µg/L/yr | 7 |
| Chlorophyll-a | ↓ Declining | +0.34 µg/L/yr | 7 |
County Ranking
Ranked #2 of 6 lakes in Mecosta County
Nearby Lakes in Mecosta County
Frequently asked questions about Round Lake
Where is Round Lake?
- Round Lake is a lake in Mecosta County, Michigan. LakeQuality grades it A for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Round Lake?
- Round Lake in Mecosta County, Michigan has a water quality grade of A (Excellent). Water clarity: 9 ft visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 6.8 µg/L. Maximum depth: 45 ft. Surface area: 156.5 acres.
Is Round Lake safe to swim in?
- The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
How deep is Round Lake?
- Round Lake has a maximum depth of 45 feet. The lake covers 156.5 acres.
Explore Round Lake across LakeQuality
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Where this data comes from
131 measurements from 1 monitoring station, 2016–2023. Retrieved from the EPA Water Quality Portal on 2026-08-26.
Collected and reported by
- Michigan EGLE - MiCorps
21MICH_MICORPS131 samples · 2016–2023
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
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.