What are oligotrophic lakes in Vermont?

26 oligotrophic lakes in Vermont. Low nutrients, clear water, excellent for swimming.

What does oligotrophic mean?

Low nutrients, clear water, excellent for swimming.

Oligotrophic Lakes in Vermont

An oligotrophic lake is what most people picture when they think of pristine northern lake country: clarity to depth, no algal scum, cold water that holds dissolved oxygen all the way to the bottom even in August. Across Vermont, 26 lakes register as oligotrophic — 0% of them break 50 feet of depth, which is the structural condition that underwrites the trophic class. Without depth and a low-nutrient watershed, oligotrophy is hard to sustain.

On our A–F scale, oligotrophic lakes almost always pull an A or B — the same low-nutrient conditions that produce the trophic class also produce the high grade.

#	Lake	County	Grade	Clarity	Depth	TSI
1	Berlin Pond	Washington	A	21.7 ft	-	32
2	Caspian Lake	Orleans	A	29.5 ft	-	32
3	Harveys Lake	Caledonia	A	21 ft	-	34
4	Maidstone Lake	Essex	A	28.5 ft	-	32
5	Seymour Lake	Orleans	A	24.6 ft	-	33
6	Lowell Lake	Windham	A	13.5 ft	-	37
7	Echo Lake	Orleans	A	23 ft	-	34
8	Echo Lake	Windsor	A	13.9 ft	-	36
9	Echo Lake	Rutland	A	24.3 ft	-	34
10	Little Averill Pond	Essex	A	19.4 ft	-	34
11	Lake Willoughby	Orleans	A	28.2 ft	-	33
12	Sunset Lake	Rutland	A	36.1 ft	-	31
13	Newark Pond	Caledonia	A	20.4 ft	-	36
14	Shadow Lake	Orleans	A	28.9 ft	-	32
15	Shadow Lake	Essex	A	16.4 ft	-	35
16	Lake Bomoseen	Rutland	A	23.6 ft	-	34
17	Forest Lake	Washington	A	25.6 ft	-	32
18	Silver Lake	Addison	A	8.2 ft	-	37
19	Great Averill Pond	Essex	A	14.3 ft	-	35
20	Lake Elligo	Orleans	A	26.2 ft	-	31
21	Green River Reservoir	Lamoille	A	13.1 ft	-	36
22	Amherst Lake	Windsor	A	15.4 ft	-	35
23	Lake Paran	Bennington	A	-	-	40
24	Sunset Lake	Windham	B	17.9 ft	-	36
25	Reservoir Pond	Windsor	B	14.7 ft	-	32
26	Lewis Pond	Essex	B	-	-	38

All oligotrophic 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 →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 Vermont lakes →

Source: EPA National Aquatic Resource Surveys, 2026.