Mesotrophic Lakes in Ohio
6 mesotrophic lakes in Ohio. Moderate nutrients, good water quality.
Most well-managed working lakes register as mesotrophic — the band that balances productivity with clarity. 6 lakes in Ohio sit in the mesotrophic band. About 0% are deep (50+ ft); the rest are shallower basins where watershed management keeps nutrients from pushing the system into eutrophy.
Mesotrophic lakes sit in the middle of the phosphorus and chlorophyll-a range: productive but still clear, with readings that rarely reach the EPA's poorest condition class.
| # | Lake | County | Clarity | Depth | TSI |
|---|---|---|---|---|---|
| 1 | Marysville Upground Reservoir | Union | - | - | 53 |
| 2 | Tiffin R Lake | Defiance | - | - | 59 |
| 3 | New Lexington Reservoir | Perry | - | - | 50 |
| 4 | Findlay Reservoir | Hancock | - | - | 51 |
| 5 | Ottawa R Lake | Allen | - | - | 60 |
| 6 | Salem Reservoir | Columbiana | - | - | 60 |
All mesotrophic lakes →Minnesota version →Wisconsin version →Illinois version →Michigan version →Iowa version →Pennsylvania version →New York version →Missouri version →Indiana version →North Dakota version →South Dakota version →Florida version →Colorado version →North Carolina version →Vermont version →Texas version →Oregon version →Arkansas version →Oklahoma version →Kansas version →Nebraska version →Nevada version →Arizona version →Idaho version →Montana version →New Mexico version →Tennessee version →Alabama version →Virginia version →Kentucky version →Utah version →Washington version →Wyoming version →Georgia version →Massachusetts version →Ontario version →Québec version →Nova Scotia version →British Columbia version →Newfoundland and Labrador version →All Ohio lakes →
Source: EPA National Aquatic Resource Surveys, 2026.