States / Vermont

14 counties · median score 35

Crawl space moisture in Vermont

Vermont is mixed: 4 of 14 counties score high or elevated, concentrated where drainage is poorest — Essex County tops the list at 60 — while Bennington County scores just 19. Where you are in the state matters more than the state itself.

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  1. 1Wettest county Essex County
  2. 2High or elevated 4 of 14
  3. 3Median score 35
  4. 4Driest county Bennington County
Essex60Grand Isle46Orleans45Franklin43Addison39Caledonia36Chittenden35Washington31Orange27Rutland26Windham21Windsor21Lamoille20Bennington19
Soil moisture score (0–100) for the 14 highest of 14 counties in Vermont, bars to scale. Score from USDA NRCS drainage class, hydrologic group, water-table depth and flooding; see methodology.
1High3Elevated9Moderate1Low
Vermont: counties by soil moisture tier, columns to scale.

Vermont's soil, taken as a whole

Across the 6,152,900 acres mapped in these 14 counties, 20% of soil with a drainage class is somewhat poorly, poorly or very poorly drained, and 42% of acres report a seasonal water table within about two metres. That is a middling figure: wet ground is common in valleys and lowlands but far from universal. 14 of the 14 counties have mapped soils subject to occasional or frequent flooding.

Drainage classShare of mapped acres
Excessively drained3.2%
Somewhat excessively drained11%
Well drained45.4%
Moderately well drained20.4%
Somewhat poorly drained4.7%
Poorly drained12.7%
Very poorly drained2.6%

Radon. By EPA zone, 0 Vermont counties here are zone 1 (highest potential), 12 zone 2 and 2 zone 3. EPA says to test regardless of zone; a sealed crawl space is the cheapest moment to add radon venting if a test calls for it.

Every Vermont county

Sorted wettest first. High and elevated counties link to their own page with the full soil breakdown.

What drives the Vermont numbers

The wettest county, Essex County, is 37% poorly drained by dominant condition, with a seasonal water table averaging 0.7 ft below grade across the 83% of acres that report one, and sits in EPA radon zone 2. The driest, Bennington County, is 66% well drained. 1 Vermont counties reach the high tier, where poorly drained soils, group D clays and a shallow water table occur together.

The score is a guide to the soil, not to a house: a well-graded lot with working gutters in a high county can have a dry crawl space, and a bad downspout can flood one in a low county. The R408 calculator sizes venting or encapsulation for any footprint.

Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted; EPA Map of Radon Zones, county table (June 2024 JSON). Checked 2026-10-23.