Mesotrophic Lakes in Idaho
4 mesotrophic lakes in Idaho. Moderate nutrients, good water quality.
Mesotrophic lakes are the productive middle of the trophic scale — TSI between 40 and 50. Clear enough to be inviting, productive enough to support a strong fishery, with moderate phosphorus and a modest algal community that does not dominate the optical signal. 4 lakes in Idaho 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 | Black Cnyn Reservoir Ns of | Gem | 7.5 ft | - | 48 |
| 2 | Lake Lowell Across From Upper Embankment | Canyon | 7.2 ft | - | 49 |
| 3 | Pasisades Reservoir | Bonneville | 10.5 ft | - | 42 |
| 4 | Palisades Lake | Bonneville | 13.1 ft | - | 42 |
All mesotrophic lakes →Minnesota version →Wisconsin version →Illinois version →Michigan version →Iowa version →Ohio 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 →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 Idaho lakes →
Source: EPA National Aquatic Resource Surveys, 2026.