Updated August 2026 · Top 25 of 119 lakes with a Secchi reading
Clearest Lake in Vermont: Top 25 by Secchi Depth
Sunset Lake in Rutland County is the clearest lake in Vermont by Secchi depth, at 36.1 ft. Mapped and ranked below: the 25 clearest of 119 Vermont lakes with a Secchi reading. Secchi depth is shown, not scored: the letter grades nutrients and algae, so a clear lake can be unrated or carry a lower grade than a murkier one.
How clear are Vermont's clearest lakes?
From 36.1 ft at Sunset Lake to 20.4 ft at #25, Newark Pond; the median of the 25 is 23.6 ft.
| # | Lake | County | Secchi depth | Grade | Area |
|---|---|---|---|---|---|
| 1 | Sunset Lake | Rutland | 36.1 ft | A | — |
| 2 | Caspian Lake | Orleans | 29.5 ft | A | 789 acres |
| 3 | Shadow Lake | Orleans | 28.9 ft | A | 199 acres |
| 4 | Maidstone Lake | Essex | 28.5 ft | A | 800 acres |
| 5 | Lake Willoughby | Orleans | 28.2 ft | A | — |
| 6 | Shadow Pond | Washington | 27.9 ft | NR | — |
| 7 | Lake Elligo | Orleans | 26.2 ft | A | — |
| 8 | Forest Lake | Washington | 25.6 ft | A | — |
| 9 | Beebe Pond | Rutland | 24.6 ft | NR | — |
| 10 | Seymour Lake | Orleans | 24.6 ft | A | 1,777 acres |
| 11 | Valley Lake | Washington | 24.4 ft | C | — |
| 12 | Echo Lake | Rutland | 24.3 ft | A | — |
| 13 | Lake Bomoseen | Rutland | 23.6 ft | A | 2,360 acres |
| 14 | Nichols Pond | Washington | 23.3 ft | NR | 167 acres |
| 15 | Echo Lake | Orleans | 23 ft | A | 508 acres |
| 16 | Berlin Pond | Washington | 21.7 ft | A | 256 acres |
| 17 | Lake Fairlee | Orange | 21.7 ft | A | 463 acres |
| 18 | Sunrise Lake | Rutland | 21.3 ft | NR | — |
| 19 | Lake Mirror | Washington | 21.3 ft | A | 86 acres |
| 20 | High Pond | Rutland | 21.3 ft | C | — |
| 21 | Spring Lake | Rutland | 21.3 ft | C | — |
| 22 | Harveys Lake | Caledonia | 21 ft | A | 409 acres |
| 23 | East Long Pond | Washington | 20.7 ft | A | 177 acres |
| 24 | Fern Lake | Addison | 20.7 ft | C | — |
| 25 | Newark Pond | Caledonia | 20.4 ft | A | — |
Sources and method
- Secchi depth: Median of each lake's EPA Water Quality Portal readings, sampled April 2020 to September 2025, in feet. Every reading in this table was submitted by Vermont Dept of Environmental Conservation. Portal: EPA Water Quality Portal.
- Grade: A–F water-quality grade from nutrient and algae sampling (total phosphorus and chlorophyll-a) against the lake's EPA ecoregion classes, where enough recent samples exist to support one; the dashed NR mark otherwise. Clarity is not part of the grade, which is why a clear lake here can be unrated or carry a lower letter than a murkier one.
- Area: state agency lake surveys and, for reservoirs, US Army Corps of Engineers National Inventory of Dams records, in acres at normal pool. A dash means no record carries one.
- Map pins: all 25 table rows, colored by grade. No other lakes are plotted.
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Frequently Asked Questions
What is the clearest lake in Vermont?
Sunset Lake in Rutland County is the clearest lake in Vermont by Secchi depth, at 36.1 ft. Secchi depth is measured by lowering a black-and-white disk until it disappears from view; a deeper reading means clearer water. Sunset Lake holds an overall water-quality grade of A.
How clear are Vermont's 25 clearest lakes?
They span 20.4 ft to 36.1 ft of Secchi depth, with a median of 23.6 ft. Sunset Lake leads by 6.6 ft. Rutland County has 7 of the 25; the rest are spread across 6 other counties. 21 of the 25 carry an A–F grade; the other 4 are not rated because their recent sampling does not support a letter.
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. The figure for each lake here is the median of its readings.
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 lakes with rocky basins and forested watersheds tend to be clearest because they take in little soil runoff and few nutrients. Shallow lakes in farmed watersheds are typically less clear because they receive more sediment and fertilizer runoff.
Is the clearest lake the cleanest?
Not always. Clarity (Secchi depth) is measured and shown; the letter grades nutrients and algae (total phosphorus and chlorophyll-a) against that lake’s EPA ecoregion classes. A lake can be very clear but still have elevated phosphorus that just hasn't bloomed yet. See our companion cleanest-lakes ranking for Vermont for the nutrient-and-algae list.
Where to stay near Vermont's clearest lakes
Planning a trip? Jump to live cabin, resort, and hotel availability near Vermont's clearest lakes.
- Sunset Lake · Rutland CountyCabins & hotels near Sunset Lake →
- Caspian Lake · Orleans CountyCabins & hotels near Caspian Lake →
- Shadow Lake · Orleans CountyCabins & hotels near Shadow Lake →
- Maidstone Lake · Essex CountyCabins & hotels near Maidstone Lake →
- Lake Willoughby · Orleans CountyCabins & hotels near Lake Willoughby →
More on water clarity
The clearest lakes in America, ranked by measured Secchi depth in feet from EPA monitoring data — and why the famously clear lakes are missing.
What a Secchi depth reading measures, how many feet counts as good clarity, and why clear water is not always clean — with readings from graded lakes.
County-by-county Secchi champions: the clearest measured lake in each county, the murkiest county winners, and why a county title is not a national one.
Surveyed maximum depth against A–F nutrient-and-algae grades: the pattern, the shallow lakes that still grade an A, and why land use beats bathymetry.