BasementSoil

Pennsylvania: basement moisture and foundation risk by county

67 counties, ranked by our combined index. Highest combined risk is Butler County (47), lowest is Clearfield County (30). The worst soil for foundation cracks specifically is in Lancaster County.

Where in Pennsylvania 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.

Adams County, PA — combined 36/100, moisture 33, movement 34, water table 46Allegheny County, PA — combined 34/100, moisture 34, movement 25, water table 46Armstrong County, PA — combined 38/100, moisture 37, movement 44, water table 30Beaver County, PA — combined 40/100, moisture 38, movement 39, water table 46Bedford County, PA — combined 34/100, moisture 33, movement 37, water table 30Berks County, PA — combined 41/100, moisture 38, movement 42, water table 46Blair County, PA — combined 38/100, moisture 37, movement 44, water table 30Bradford County, PA — combined 40/100, moisture 37, movement 52, water table 30Bucks County, PA — combined 45/100, moisture 34, movement 60, water table 46Butler County, PA — combined 47/100, moisture 37, movement 48, water table 66Cambria County, PA — combined 35/100, moisture 36, movement 38, water table 30Cameron County, PA — combined 36/100, moisture 36, movement 29, water table 46Carbon County, PA — combined 36/100, moisture 33, movement 46, water table 30Centre County, PA — combined 43/100, moisture 36, movement 52, water table 46Chester County, PA — combined 34/100, moisture 34, movement 37, water table 30Clarion County, PA — combined 41/100, moisture 36, movement 45, water table 46Clearfield County, PA — combined 30/100, moisture 37, movement 30, water table 16Clinton County, PA — combined 41/100, moisture 34, movement 47, water table 46Columbia County, PA — combined 39/100, moisture 37, movement 37, water table 46Crawford County, PA — combined 33/100, moisture 34, movement 44, water table 16Cumberland County, PA — combined 41/100, moisture 36, movement 55, water table 30Dauphin County, PA — combined 34/100, moisture 33, movement 37, water table 30Delaware County, PA — combined 35/100, moisture 35, movement 40, water table 30Elk County, PA — combined 37/100, moisture 34, movement 47, water table 30Erie County, PA — combined 39/100, moisture 38, movement 36, water table 46Fayette County, PA — combined 34/100, moisture 36, movement 43, water table 16Forest County, PA — combined 38/100, moisture 34, movement 48, water table 30Franklin County, PA — combined 34/100, moisture 33, movement 49, water table 16Fulton County, PA — combined 37/100, moisture 36, movement 43, water table 30Greene County, PA — combined 39/100, moisture 38, movement 46, water table 30Huntingdon County, PA — combined 39/100, moisture 34, movement 40, water table 46Indiana County, PA — combined 37/100, moisture 35, movement 44, water table 30Jefferson County, PA — combined 37/100, moisture 38, movement 42, water table 30Juniata County, PA — combined 30/100, moisture 37, movement 30, water table 16Lackawanna County, PA — combined 34/100, moisture 34, movement 48, water table 16Lancaster County, PA — combined 40/100, moisture 36, movement 63, water table 16Lawrence County, PA — combined 36/100, moisture 36, movement 30, water table 46Lebanon County, PA — combined 39/100, moisture 36, movement 49, water table 30Lehigh County, PA — combined 34/100, moisture 34, movement 36, water table 30Luzerne County, PA — combined 36/100, moisture 33, movement 43, water table 30Lycoming County, PA — combined 44/100, moisture 36, movement 53, water table 46McKean County, PA — combined 40/100, moisture 38, movement 39, water table 46Mercer County, PA — combined 32/100, moisture 37, movement 38, water table 16Mifflin County, PA — combined 39/100, moisture 36, movement 51, water table 30Monroe County, PA — combined 35/100, moisture 35, movement 39, water table 30Montgomery County, PA — combined 45/100, moisture 37, movement 56, water table 46Montour County, PA — combined 42/100, moisture 35, movement 50, water table 46Northampton County, PA — combined 41/100, moisture 37, movement 55, water table 30Northumberland County, PA — combined 40/100, moisture 37, movement 50, water table 30Perry County, PA — combined 32/100, moisture 35, movement 39, water table 16Philadelphia County, PA — combined 42/100, moisture 38, movement 46, water table 46Pike County, PA — combined 39/100, moisture 36, movement 51, water table 30Potter County, PA — combined 36/100, moisture 36, movement 29, water table 46Schuylkill County, PA — combined 44/100, moisture 35, movement 56, water table 46Snyder County, PA — combined 33/100, moisture 37, movement 29, water table 30Somerset County, PA — combined 33/100, moisture 37, movement 30, water table 30Sullivan County, PA — combined 38/100, moisture 35, movement 47, water table 30Susquehanna County, PA — combined 37/100, moisture 36, movement 43, water table 30Tioga County, PA — combined 36/100, moisture 35, movement 42, water table 30Union County, PA — combined 38/100, moisture 36, movement 36, water table 46Venango County, PA — combined 41/100, moisture 38, movement 27, water table 66Warren County, PA — combined 36/100, moisture 36, movement 39, water table 30Washington County, PA — combined 35/100, moisture 36, movement 25, water table 46Wayne County, PA — combined 32/100, moisture 35, movement 29, water table 30Westmoreland County, PA — combined 39/100, moisture 35, movement 52, water table 30Wyoming County, PA — combined 40/100, moisture 36, movement 42, water table 46York County, PA — combined 40/100, moisture 36, movement 54, water table 30
  • 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
Butler County47374866Appalachian Plateau
Bucks County45346046Piedmont
Montgomery County45375646Piedmont
Lycoming County44365346Appalachian Plateau
Schuylkill County44355646Ridge and Valley
Centre County43365246Ridge and Valley
Montour County42355046Ridge and Valley
Philadelphia County42384646Piedmont
Berks County41384246Piedmont
Clarion County41364546Appalachian Plateau
Clinton County41344746Ridge and Valley
Cumberland County41365530Ridge and Valley
Northampton County41375530Ridge and Valley
Venango County41382766Appalachian Plateau
Beaver County40383946Appalachian Plateau
Bradford County40375230Appalachian Plateau
Lancaster County40366316Piedmont
McKean County40383946Appalachian Plateau
Northumberland County40375030Ridge and Valley
Wyoming County40364246Appalachian Plateau
York County40365430Ridge and Valley
Columbia County39373746Ridge and Valley
Erie County39383646Appalachian Plateau
Greene County39384630Appalachian Plateau
Huntingdon County39344046Ridge and Valley
Lebanon County39364930Piedmont
Mifflin County39365130Ridge and Valley
Pike County39365130Appalachian Plateau
Westmoreland County39355230Appalachian Plateau
Armstrong County38374430Appalachian Plateau
Blair County38374430Ridge and Valley
Forest County38344830Appalachian Plateau
Sullivan County38354730Appalachian Plateau
Union County38363646Ridge and Valley
Elk County37344730Appalachian Plateau
Fulton County37364330Ridge and Valley
Indiana County37354430Appalachian Plateau
Jefferson County37384230Appalachian Plateau
Susquehanna County37364330Appalachian Plateau
Adams County36333446Ridge and Valley
Cameron County36362946Appalachian Plateau
Carbon County36334630Ridge and Valley
Lawrence County36363046Appalachian Plateau
Luzerne County36334330Ridge and Valley
Potter County36362946Appalachian Plateau
Tioga County36354230Appalachian Plateau
Warren County36363930Appalachian Plateau
Cambria County35363830Ridge and Valley
Delaware County35354030Piedmont
Monroe County35353930Ridge and Valley
Washington County35362546Appalachian Plateau
Allegheny County34342546Appalachian Plateau
Bedford County34333730Ridge and Valley
Chester County34343730Piedmont
Dauphin County34333730Ridge and Valley
Fayette County34364316Appalachian Plateau
Franklin County34334916Ridge and Valley
Lackawanna County34344816Appalachian Plateau
Lehigh County34343630Ridge and Valley
Crawford County33344416Appalachian Plateau
Snyder County33372930Ridge and Valley
Somerset County33373030Appalachian Plateau
Mercer County32373816Appalachian Plateau
Perry County32353916Ridge and Valley
Wayne County32352930Appalachian Plateau
Clearfield County30373016Ridge and Valley
Juniata County30373016Ridge and Valley

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

The physiographic regions inside Pennsylvania

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

Appalachian Plateau

Water travels over bedrock under a thin skin of colluvium. A house cut into a hillside has an entire catchment behind its uphill wall — what decides the outcome here is a daylight drain, not a coating.

32 counties: Allegheny County, Armstrong County, Beaver County, Bradford County, Butler County, Cameron County, Clarion County, Crawford County, Elk County, Erie County, Fayette County, Forest County, Greene County, Indiana County, Jefferson County, Lackawanna County, Lawrence County, Lycoming County, McKean County, Mercer County, Pike County, Potter County, Somerset County, Sullivan County, Susquehanna County, Tioga County, Venango County, Warren County, Washington County, Wayne County, Westmoreland County, Wyoming County

Ridge and Valley

Limestone valleys mean karst: permeability is excellent until it is not. Sinkhole activity is an underrated cause of foundation failure here.

27 counties: Adams County, Bedford County, Blair County, Cambria County, Carbon County, Centre County, Clearfield County, Clinton County, Columbia County, Cumberland County, Dauphin County, Franklin County, Fulton County, Huntingdon County, Juniata County, Lehigh County, Luzerne County, Mifflin County, Monroe County, Montour County, Northampton County, Northumberland County, Perry County, Schuylkill County, Snyder County, Union County, York County

Piedmont

Saprolite is weathered rock that keeps its structure, so water moves through it along relict joints unpredictably. The Triassic basins inside the Piedmont are islands of strongly expansive clay.

8 counties: Berks County, Bucks County, Chester County, Delaware County, Lancaster County, Lebanon County, Montgomery County, Philadelphia County

Page data updated