Clearest Lakes in Vermont: Top 25 by Secchi Depth

The single clearest lake in Vermont is Sunset Lake in Rutland County, with a Secchi depth of 36.1 feet — meaning a Secchi disk lowered from the surface disappears at that depth. Sunset Lake holds an overall water quality grade of A. The 25 clearest lakes in Vermont are ranked below by 2026 measurements.

Secchi depth is the standard scientific measure of lake water clarity. Greater depth means clearer water. Below, the 25 clearest lakes in Vermont from 2026 EPA and Vermont state-agency sampling.

How clear are Vermont's clearest lakes?

Across the 165 Vermont lakes with Secchi clarity readings in our 2026 dataset, the 25 clearest range from 20.7 to 36.1 feet of visibility. Sunset Lake sits at the top, 6.6 ft clearer than the next lake on the list, well above the 24.3-foot median of this leading group — a spread that shows how quickly clarity falls off once you move past a state's handful of truly pristine waters.

The clearest water is not spread evenly. Rutland County alone accounts for 7 of the 25 top-ranked lakes, with the rest drawn from 6 other counties. That clustering follows the terrain: deep, glacially carved basins ringed by forest take in little sediment or fertilizer runoff, so phosphorus stays low and the water stays transparent.

Clarity and overall health usually align here: 25 of these 25 lakes also earn an A- or B-range overall grade. Where the two diverge — a clear lake carrying a weaker grade — the cause is typically elevated phosphorus that transparency alone can't reveal, which is why our grade combines phosphorus and chlorophyll-a with Secchi depth rather than relying on clarity by itself.

Rank	Lake	County	Secchi Depth	Grade	Max Depth	Area
1	Sunset Lake	Rutland	36.1 ft	A	-	-
2	Caspian Lake	Orleans	29.5 ft	A	-	-
3	Shadow Lake	Orleans	28.9 ft	A	-	-
4	Maidstone Lake	Essex	28.5 ft	A	-	-
5	Lake Willoughby	Orleans	28.2 ft	A	-	-
6	Shadow Pond	Washington	27.9 ft	A	-	-
7	Lake Elligo	Orleans	26.2 ft	A	-	-
8	Forest Lake	Washington	25.6 ft	A	-	-
9	Miller Pond	Orange	24.8 ft	A	-	-
10	Beebe Pond	Rutland	24.6 ft	A	-	-
11	Seymour Lake	Orleans	24.6 ft	A	-	-
12	Valley Lake	Washington	24.4 ft	A	-	-
13	Echo Lake	Rutland	24.3 ft	A	-	-
14	Lake Bomoseen	Rutland	23.6 ft	A	-	-
15	Nichols Pond	Washington	23.3 ft	A	-	-
16	Echo Lake	Orleans	23 ft	A	-	-
17	Berlin Pond	Washington	21.7 ft	A	-	-
18	Lake Fairlee	Orange	21.7 ft	A	-	-
19	Sunrise Lake	Rutland	21.3 ft	A	-	-
20	Lake Mirror	Washington	21.3 ft	A	-	-
21	High Pond	Rutland	21.3 ft	A	-	-
22	Spring Lake	Rutland	21.3 ft	A	-	-
23	Harveys Lake	Caledonia	21 ft	A	-	-
24	East Long Pond	Washington	20.7 ft	A	-	-
25	Fern Lake	Addison	20.7 ft	A	-	-

Where to stay near Vermont's clearest lakes

Planning a trip? Jump to live cabin, resort, and hotel availability near Vermont's clearest lakes.

Clearest lakes across all states →Cleanest lakes in Vermont (combined score) →All Vermont lakes →

Frequently Asked Questions

What is the clearest lake in Vermont?

Sunset Lake is the clearest lake in Vermont by Secchi depth, with water transparency of 36.1 feet. Secchi depth is measured by lowering a black-and-white disk until it disappears from view — deeper readings mean clearer water. Located in Rutland County, Sunset Lake holds an overall water quality grade of A.

How is water clarity measured?

Water clarity is measured by Secchi depth, named after the 19th-century Italian astronomer Pietro Angelo Secchi who developed the method. A standardized black-and-white disk is lowered into the water on a rope; the depth (in feet or meters) at which the disk disappears from view is recorded. Greater Secchi depth means clearer water — usually a sign of low sediment, low phosphorus, and limited algae growth.

What makes a lake clear?

Lake clarity is driven by three factors: low suspended sediment (clay, silt), low nutrient load (especially phosphorus, which fuels algae), and low chlorophyll-a (active algae biomass). Deep glacial lakes with rocky basins and forested watersheds — common in northern Vermont — tend to be clearest because they have little soil runoff and limited nutrient input. Shallow agricultural-watershed lakes are typically less clear because they receive more sediment and fertilizer runoff.

Is the clearest lake the cleanest?

Not always. Clarity (Secchi depth) is one of three indicators we use; the others are total phosphorus and chlorophyll-a. A lake can be very clear but still have elevated phosphorus that just hasn't bloomed yet, or chlorophyll-a from a recent bloom that's still settling. The most reliable measure of overall lake health is the combined grade, which weights all three signals. See our companion cleanest-lakes ranking for Vermont for the combined-score list.

How does Vermont compare to other states?

Vermont's clearest waters compete with the most pristine lakes in our 17-state dataset, where top-tier lakes typically register Secchi depths of 15–25 feet. Nationally, the gold standard is Crater Lake in Oregon (~100 ft) and Lake Tahoe (~65 ft).

Source: EPA National Aquatic Resource Surveys + state DNR Secchi sampling, 2026.