Eutrophic Lakes in Ohio
12 eutrophic lakes in Ohio. High nutrients, frequent algae, reduced clarity.
Eutrophic lakes — TSI 50 to 70 — are nutrient-rich and productive, with persistent summer algal communities that drive visible reductions in clarity. These conditions are not failures; they reflect a lake doing what nutrient-loaded waters do. 12 Ohio lakes register as eutrophic. Only 0% are deep — eutrophy correlates with shallowness, agricultural watersheds, and the kind of nutrient-input history that takes decades to shift.
Eutrophic lakes typically carry higher phosphorus and chlorophyll-a readings. The same nutrient richness that defines the trophic class shows up in those numbers.
| # | Lake | County | Clarity | Depth | TSI |
|---|---|---|---|---|---|
| 1 | Powers Reservoir | Crawford | - | - | 56 |
| 2 | Lost Creek Reservoir | Allen | - | - | 51 |
| 3 | Fremont Reservoir | Sandusky | - | - | 57 |
| 4 | Ferguson Reservoir | Allen | - | - | 65 |
| 5 | Williams Reservoir | Allen | - | - | 59 |
| 6 | Caesar Creek Lake | Warren | 3.2 ft | - | 57 |
| 7 | Upper Sandusky Reservoir | Wyandot | - | - | 63 |
| 8 | Burr Oak Reservoir | Morgan | - | - | 59 |
| 9 | Lake Logan | Hocking | - | - | 61 |
| 10 | Metzger Reservoir | Allen | - | - | 62 |
| 11 | Twin Lakes Reservoir | Allen | - | - | 68 |
| 12 | Ottawa Reservoir | Putnam | - | - | 66 |
All eutrophic 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.