Some of these decisions are not final. 14 of these 712 records carry a verdict Vermont decided in its 2026 Integrated Report, which is open for public comment, so they can change before the cycle is submitted to EPA. They are counted in every figure on this page.
State water-quality picture · #12 by reported lake-type waterbodies
Vermont lakes and reservoirs
Every figure on this page is computed from the assessment decisions Vermont reported to the U.S. Environmental Protection Agency under Clean Water Act sections 303(d) and 305(b) (reporting cycles 2006–2026), plus daily water-level observations from the U.S. Geological Survey.
- 712
- Reported waterbodies
- 154
- Not supporting a use
- 44
- Fish use not supporting
- 0
- Gauged lakes
Vermont in one line
712 lake-type waterbodies in Vermont are reported to EPA ATTAINS across reporting cycles 2006–2026: 154 assessed as not supporting at least one designated use, 558 fully supporting, and 0 without a definitive overall verdict. The most-listed impairment cause is Eurasian Water Milfoil, Myriophyllum Spicatum, on 71 waterbodies.
- 712
- reported waterbodies
- 154
- not supporting a use
- 558
- fully supporting
- 22%
- of definitive verdicts impaired
An unassessed waterbody is neither confirmed clean nor confirmed impaired; states assess on multi-year cycles.
A large Vermont inventory with a lighter ruled-impairment share
712 reported lake-type units put Vermont in the largest third of state registers, while its ruled not-supporting share (22%) sits in the lowest third. Scale and load pull apart on this page.
Data updated 2026-08-17
According to the U.S. Environmental Protection Agency's ATTAINS program, Vermont reported 712 lake-type waterbodies in Vermont in the August 2026 extract. See our methodology for filer attribution and multi-year reporting cycles.
How Vermont's large inventory splits across overall status
Each of the 712 lake-type units reported by Vermont lands in exactly one overall-status bucket. On a register this large, the bar is an inventory partition, the cause chart and national gauge below answer different questions.
Most-listed impairment causes in Vermont
Waterbodies carrying each listed cause, most first
- Eurasian Water Milfoil, Myriophyllum Spicatum
Eurasian Water Milfoil, Myriophyllum Spicatum
71 waterbodies
- Mercury in Fish Tissue
Mercury in Fish Tissue
45 waterbodies
- Phosphorus
Phosphorus
39 waterbodies
- pH
pH
30 waterbodies
- PCBs in Fish Tissue 28
PCBs in Fish Tissue
28 waterbodies
What this shows Eurasian Water Milfoil, Myriophyllum Spicatum is the most-listed impairment cause in Vermont, on 71 of the lake-type waterbodies reported there.
Computed share from EPA ATTAINS filed records, not an official EPA rating or safety grade.
Vermont: 22% of ruled verdicts are not-supporting, against a national share of 53%, 2.4× below the national rate.
Reporting practice
Nearly all of Vermont's inventory carries a definitive verdict
Each reporting authority decides how much of the water it files to EPA it actually assesses in a cycle. That decision sets the denominator behind every count on this page.
Vermont holds the 12th-largest reported lake-type inventory in the country, 712 assessment units, carrying a definitive verdict on 100% of it. Every reported unit carries a verdict, so the counts above describe the whole reported inventory.
The states reporting at the nearest rates are Pennsylvania (100%) and New Hampshire (99.9%).
Assessing more of an inventory is a reporting choice, set by cycle length, monitoring budget and how finely a state splits its waters into units. It is not a measure of water quality, and it is why a raw count from one state does not sit beside a raw count from another. How assessment coverage varies.
Vermont against every comparable state
Share of reported lake-type waterbodies carrying a definitive verdict
100% 1st of 47 higher than 45 of 47 states
the 47 comparable states, by definitive-verdict share
Each bar is a band; taller bars hold more states. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA ATTAINS · Reporting cycles 1987–2026
Each bar counts states whose definitive-verdict share falls in that 10-point band. The 47 states shown are those reporting at least 25 lake-type units; a share off a smaller inventory is precision the data does not have.
By size
Largest assessed lakes in Vermont
By assessed acreage as reported in ATTAINS. Acreage is the assessed unit's size, which can differ from a lake's full surface area.
| # | Waterbody | Assessed acres |
|---|---|---|
| 1 | Champ-Northeast Arm Not Supporting | 57,022 |
| 2 | Champ-Main Lake Not Supporting | 37,809 |
| 3 | Champ-Isle La Motte Not Supporting | 20,962 |
| 4 | Champ-Malletts Bay Not Supporting | 12,049 |
| 5 | Champ-Port Henry Not Supporting | 8,372 |
| 6 | Champ-Missisquoi Bay Not Supporting | 6,398 |
| 7 | Memphremagog Not Supporting | 5,660 |
| 8 | Champ-South Lake a Not Supporting | 4,385 |
| 9 | Champ-Otter Creek Not Supporting | 3,981 |
| 10 | Champ-Burlington Bay Not Supporting | 2,273 |
| 11 | Harriman (Whithm) Not Supporting | 2,040 |
| 12 | Champ-St. Albans Bay Not Supporting | 1,999 |
By cause count
Most-listed waterbodies in Vermont
Waterbodies carrying the most listed impairment causes among the lake-type units reported by Vermont.
| # | Waterbody | Listed causes |
|---|---|---|
| 1 | Bomoseen Not Supporting | 6 |
| 1 | Champ-Missisquoi Bay Not Supporting | 6 |
| 1 | Champ-Otter Creek Not Supporting | 6 |
| 4 | Champ-Burlington Bay Not Supporting | 5 |
| 4 | Champ-Isle La Motte Not Supporting | 5 |
| 4 | Champ-Malletts Bay Not Supporting | 5 |
| 4 | Champ-Northeast Arm Not Supporting | 5 |
| 4 | Champ-Port Henry Not Supporting | 5 |
| 4 | Champ-Shelburne Bay Not Supporting | 5 |
| 4 | Champ-South Lake a Not Supporting | 5 |
Every row in this table ties with at least one other on the ranked value: 3 at 6 (rank 1), 7 at 5 (rank 4). Tied rows share a rank and are listed in no meaningful order; where a tie reaches the top the medal is shared, because nothing separates those rows.
States near Vermont's lighter not-supporting load
Two EPA ATTAINS peer sets outside Vermont. The reporting-practice chart above stays on definitive-verdict share; these neighborhoods highlight register-size and not-supporting peers while Vermont's ruled impairment share sits in the lowest third.
Similar reported inventory
Nearest states by lake-type units on the register (712 here).
- Illinois · 783 units · 71 off
- Idaho · 630 units · 82 off
- Missouri · 623 units · 89 off
- New Jersey · 611 units · 101 off
Comparable not-supporting counts
Nearest states by units assessed not supporting a use (154 here). Inventory peers above are omitted.
- Oklahoma · 153 not supporting · 1 off
- Indiana · 145 not supporting · 9 off
- South Dakota · 145 not supporting · 9 off
- Oregon · 165 not supporting · 11 off
Peers are nearest-neighbor matches on EPA ATTAINS register size and not-supporting counts among states with at least 25 reported units. Impairment peers skip states already listed in the inventory column so the two link sets stay distinct.
Using this state picture
- Comparisons across states hold on shares, not counts: 100% of the inventory reported from Vermont carries a definitive verdict, 1st of 47 comparable states. National rankings
- Fish-consumption verdicts here are assessment decisions. Species-level meal advice comes from the state fish-advisory program. Consumption guide
- Browse every named Vermont waterbody with a populated record. Browse waterbodies
PlainLakes renders state assessment decisions and federal gauge observations without modification.
Figures on this page are computed from the assessment decisions Vermont reported to EPA's ATTAINS system and from USGS National Water Information System daily values, no number is typed in by an editor. State counts aggregate every lake-type assessment unit reported by Vermont, including unnamed units that never receive their own page. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-08-17. Primary sources: EPA ATTAINS and USGS National Water Information System.