BasementSoil

Rhode Island: basement moisture and foundation risk by county

5 counties, ranked by our combined index. Highest combined risk is Kent County (42), lowest is Newport County (33). The worst soil for foundation cracks specifically is in Newport County.

Where in Rhode Island the ground is worse

Every county in the state, coloured by the soil values below. Click a county to open its report; switch what the colour means with the buttons. The pattern is geology, not administration — risk stops at the edge of a physiographic region, not at a county line.

Bristol County, RI — combined 34/100, moisture 41, movement 14, water table 46Kent County, RI — combined 42/100, moisture 44, movement 23, water table 66Newport County, RI — combined 33/100, moisture 40, movement 25, water table 30Providence County, RI — combined 35/100, moisture 41, movement 18, water table 46Washington County, RI — combined 37/100, moisture 39, movement 14, water table 66
  • Low (0–27)
  • Moderate (28–49)
  • Elevated (50–74)
  • High (75–100)

County boundaries: US Census TIGER (public domain), simplified for display. Colours are our index from USDA SSURGO fields where loaded, otherwise from our regional model — each county page states which. How the index is calculated.

CountyIndexMoistureCracksWater tableRegion
Kent County42442366Glaciated New England upland
Washington County37391466Atlantic coastal plain
Providence County35411846Glaciated New England upland
Bristol County34411446Glaciated New England upland
Newport County33402530Glaciated New England upland

Values from USDA NRCS SSURGO where available, otherwise our regional model — each county page states which. Methodology.

The physiographic regions inside Rhode Island

State lines are political; soil follows geology. These are the distinct ground types inside Rhode Island and why each behaves the way it does.

Glaciated New England upland

A hardpan under thin till creates a perched water table — water stands above an impermeable layer even though the regional water table is deep. It is the commonest cause of a wet basement in New England. Expansive clay is largely absent.

4 counties: Bristol County, Kent County, Newport County, Providence County

Atlantic coastal plain

Extremely variable over short distances: sand and saturated clay side by side. A county figure means less here than anywhere else we cover — the individual parcel decides.

1 counties: Washington County

Page data updated