Chittenden County, Vermont
A shallow water table limits basements on 39% of Chittenden County's mapped land, a higher share than 57% of US counties and the 7th highest of 14 Vermont counties. Shrink-swell clay limits houses without basements on 3%.
10% of the county is in drought on the October 13, 2026 Drought Monitor map, up from 0% a week earlier. FEMA's flood data list 71 flood losses here since 2016, 61% of them in buildings with basements. 48% of homes were built before 1980, against 50% nationally; the median home dates from 1981.
Data as of October 13, 2026 · sources
expansive clay: shrink-swell limits slab homes
high water table: limits basements
in drought, October 13, 2026
of homes built before 1980
Soil under Chittenden County
| Expansive clay (limits slab homes) | 2.7% |
| High water table (limits basements) | 39.1% |
| Septic fields very limited | 80.6% |
| Clay swell (LEP, by area) | 1.6% |
| High-swell land (LEP 6%+) | 2.7% |
| Mapped soil | 391,991 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Lyman | 13% | n/a |
| Peru | 11% | n/a |
| Marlow | 9% | n/a |
| Cabot | 5% | n/a |
| Vergennes | 4% | n/a |
| Farmington | 4% | n/a |
How we count · survey areas VT007 (2025-09-16)
What the numbers mean here
On 39% of Chittenden County's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.
Rain over the 12 months to August 2026: 43.72 in, 0.74 in above the 1991-2020 average year of 42.98 in.
USDA rates 81% of the land very limited for septic absorption fields.
Drought
10% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 5 of the last 52 weeks; the most was 100% of its area, in 3 weeks, most recently on the November 4, 2025 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 10% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
71 flood losses since 2016, $1.5 million paid. The worst year was 2023, with 43. Foundations of the buildings, where recorded: 61% basements, 15% slabs, 12% crawl spaces, 12% elevated. Median water depth outside the building: 16 in.
| Year | Flood losses |
|---|---|
| 2016 | 2 |
| 2017 | 0 |
| 2018 | 2 |
| 2019 | 6 |
| 2020 | 1 |
| 2021 | 0 |
| 2022 | 2 |
| 2023 | 43 |
| 2024 | 14 |
| 2025 | 0 |
| 2026 to date | 1 |
Rain
| Average year, 1991-2020 | 42.98 in |
| 12 months to August 2026 | 43.72 in (+0.74) |
| 2025 | 41.32 in (-1.66) |
| Wettest year since 1895 | 2011: 55.64 in |
| Driest year since 1895 | 1941: 28.55 in |
| Days with 1 inch or more, normal at BURLINGTON INTL AP (4 mi away) | 6.7 |
Homes
| Housing units | 74,888 |
| Median year built | 1981 |
| Built before 1980 | 48% |
| Built 2000 or later | 22% |
| Owner-occupied | 64% |
| Median value, owner-occupied | $439,200 |
| Single-family detached | 52% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Lamoille County, VT | 24 mi | 0% | 24% |
| Washington County, VT | 25 mi | 0% | 35% |
| Grand Isle County, VT | 26 mi | 21% | 65% |
| Franklin County, VT | 28 mi | 1% | 52% |
| Addison County, VT | 30 mi | 5% | 53% |
| Clinton County, NY | 37 mi | 3% | 51% |
| Essex County, NY | 43 mi | 3% | 31% |
| Orange County, VT | 47 mi | 0% | 36% |
Sources: USDA SSURGO (September 16, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status