Hypereutrophic Lakes in Massachusetts
9 hypereutrophic lakes in Massachusetts. Very high nutrients, dense algae, poor clarity.
Hypereutrophic lakes (TSI above 70) are at the upper end of the productivity scale: visible algal blooms most weeks of summer, clarity often under 3 feet, and meaningful risk of harmful-algal-bloom toxin events. 9 hypereutrophic lakes are on the Massachusetts books. Almost none of them are deep — 0% break 50 feet. Shallow basin plus heavy nutrient input is the consistent recipe.
Hypereutrophic lakes carry the highest phosphorus and chlorophyll-a readings on record; the trophic class and the readings are measuring closely related dimensions of the same underlying nutrient regime.
| # | Lake | County | Clarity | Depth | TSI |
|---|---|---|---|---|---|
| 1 | Nashawannuck Pond | Hampshire | - | - | 65 |
| 2 | Bartlett Pond | Worcester | - | - | 66 |
| 3 | Gleasons Pond | Middlesex | - | - | 68 |
| 4 | Barkers Pond | Middlesex | - | - | 70 |
| 5 | Furnace Pond | Plymouth | - | - | 68 |
| 6 | Mill Pond | Barnstable | - | - | 64 |
| 7 | Cooks Pond | Plymouth | - | - | 69 |
| 8 | South Watuppa Pond | Bristol | - | - | 68 |
| 9 | Wedge Pond | Middlesex | - | - | 72 |
All hypereutrophic 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 →Idaho version →Montana version →New Mexico version →Tennessee version →Alabama version →Virginia version →Kentucky version →Utah version →Washington version →Wyoming version →Georgia version →Ontario version →Québec version →Nova Scotia version →British Columbia version →Newfoundland and Labrador version →All Massachusetts lakes →
Source: EPA National Aquatic Resource Surveys, 2026.