Fluoride in Vermont well water
In Vermont, <1% of 23,363 private wells tested had fluoride above the Vermont limit (4 mg/L), according to the Vermont Department of Health.
Natural fluoride in bedrock wells can exceed the limit. Above 4 mg/L long-term exposure causes skeletal fluorosis; above 2 mg/L children can develop tooth mottling.
By county, from homeowner tests
Share of private wells above the state guidance level (4 mg/L) in tests homeowners sent to the state lab, to .
| County | Wells tested | Above state level | Highest | |
|---|---|---|---|---|
| Addison | 1,833 | <1% | 15.7 mg/L | |
| Grand Isle | 377 | <1% | 9.74 mg/L | |
| Windham | 1,629 | <1% | 4.78 mg/L | |
| Chittenden | 5,062 | <1% | 7.2 mg/L | |
| Orange | 1,283 | <1% | 6.43 mg/L | |
| Orleans | 1,151 | <1% | 4.3 mg/L | |
| Rutland | 1,338 | <1% | 4.27 mg/L | |
| Franklin | 2,576 | <1% | 5.3 mg/L | |
| Washington | 2,784 | 0% | 1.54 mg/L | |
| Windsor | 1,930 | 0% | 1.6 mg/L | |
| Lamoille | 1,709 | 0% | 1.1 mg/L | |
| Caledonia | 970 | 0% | 3.9 mg/L | |
| Bennington | 586 | 0% | 1.29 mg/L | |
| Essex | 135 | 0% | 1.13 mg/L |
Towns with the highest share above the state level
- Westminster, Windham County3% of 137 wells
- Ferrisburgh, Addison County3% of 227 wells
- Topsham, Orange County2% of 47 wells
- Orwell, Addison County2% of 65 wells
- Tunbridge, Orange County1% of 85 wells
- Greensboro, Orleans County1% of 95 wells
- Poultney, Rutland County1% of 92 wells
- Charlotte, Chittenden County<1% of 677 wells
- Westford, Chittenden County<1% of 249 wells
- South Hero, Grand Isle County<1% of 157 wells
- Georgia, Franklin County<1% of 429 wells
- Stowe, Lamoille County0% of 570 wells
- Fairfax, Franklin County0% of 489 wells
- Jericho, Chittenden County0% of 484 wells
- Richmond, Chittenden County0% of 478 wells
- Colchester, Chittenden County0% of 421 wells
- Hinesburg, Chittenden County0% of 421 wells
- Milton, Chittenden County0% of 393 wells
- Underhill, Chittenden County0% of 392 wells
- Williston, Chittenden County0% of 371 wells
- Essex, Chittenden County0% of 339 wells
- Waterbury, Washington County0% of 333 wells
- Cambridge, Lamoille County0% of 300 wells
- Swanton, Franklin County0% of 267 wells
- Morristown, Lamoille County0% of 261 wells
Sources
- Vermont Tracking private well summaries: Town summaries of private well tests reported to the Vermont Department of Health, published through Vermont Environmental Public Health Tracking. Shares are against the limit Vermont applies to each analyte: arsenic 10 ug/L, uranium 20 ug/L (stricter than EPA), fluoride 4 mg/L, nitrate 10 mg/L, gross alpha 15 pCi/L, radon 4,000 pCi/L advisory. Only towns with 20 or more results are published; statistics below the reporting limit show as *. Retrieved September 3, 2026.
- Individual samples from the USGS Water Quality Portal and state monitoring, summarized per geography. fluoride counts and shares are listed on each county and town page with their sources.