BasementSoil

North Carolina: basement moisture and foundation risk by county

100 counties, ranked by our combined index. Highest combined risk is Moore County (53), lowest is Buncombe County (25). The worst soil for foundation cracks specifically is in Cleveland County.

Where in North Carolina 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.

Alamance County, NC — combined 40/100, moisture 44, movement 17, water table 66Alexander County, NC — combined 37/100, moisture 34, movement 57, water table 16Alleghany County, NC — combined 39/100, moisture 38, movement 36, water table 46Anson County, NC — combined 36/100, moisture 36, movement 41, water table 30Ashe County, NC — combined 43/100, moisture 37, movement 48, water table 46Avery County, NC — combined 34/100, moisture 38, movement 30, water table 30Beaufort County, NC — combined 50/100, moisture 43, movement 47, water table 66Bertie County, NC — combined 50/100, moisture 42, movement 37, water table 82Bladen County, NC — combined 43/100, moisture 42, movement 28, water table 66Brunswick County, NC — combined 43/100, moisture 41, movement 17, water table 82Buncombe County, NC — combined 25/100, moisture 33, movement 20, water table 16Burke County, NC — combined 33/100, moisture 34, movement 34, water table 30Cabarrus County, NC — combined 40/100, moisture 36, movement 41, water table 46Caldwell County, NC — combined 36/100, moisture 35, movement 43, water table 30Camden County, NC — combined 38/100, moisture 41, movement 29, water table 46Carteret County, NC — combined 37/100, moisture 44, movement 20, water table 46Caswell County, NC — combined 50/100, moisture 44, movement 34, water table 82Catawba County, NC — combined 34/100, moisture 35, movement 45, water table 16Chatham County, NC — combined 45/100, moisture 42, movement 24, water table 82Cherokee County, NC — combined 37/100, moisture 32, movement 39, water table 46Chowan County, NC — combined 45/100, moisture 44, movement 47, water table 46Clay County, NC — combined 28/100, moisture 34, movement 29, water table 16Cleveland County, NC — combined 45/100, moisture 38, movement 65, water table 30Columbus County, NC — combined 46/100, moisture 42, movement 25, water table 82Craven County, NC — combined 44/100, moisture 44, movement 44, water table 46Cumberland County, NC — combined 43/100, moisture 40, movement 32, water table 66Currituck County, NC — combined 49/100, moisture 44, movement 33, water table 82Dare County, NC — combined 39/100, moisture 44, movement 26, water table 46Davidson County, NC — combined 39/100, moisture 36, movement 38, water table 46Davie County, NC — combined 30/100, moisture 38, movement 30, water table 16Duplin County, NC — combined 45/100, moisture 41, movement 49, water table 46Durham County, NC — combined 43/100, moisture 43, movement 25, water table 66Edgecombe County, NC — combined 36/100, moisture 41, movement 22, water table 46Forsyth County, NC — combined 48/100, moisture 38, movement 64, water table 46Franklin County, NC — combined 41/100, moisture 40, movement 23, water table 66Gaston County, NC — combined 34/100, moisture 38, movement 41, water table 16Gates County, NC — combined 47/100, moisture 41, movement 43, water table 66Graham County, NC — combined 37/100, moisture 32, movement 39, water table 46Granville County, NC — combined 45/100, moisture 43, movement 48, water table 46Greene County, NC — combined 43/100, moisture 40, movement 30, water table 66Guilford County, NC — combined 43/100, moisture 36, movement 52, water table 46Halifax County, NC — combined 41/100, moisture 43, movement 34, water table 46Harnett County, NC — combined 40/100, moisture 43, movement 17, water table 66Haywood County, NC — combined 31/100, moisture 31, movement 33, water table 30Henderson County, NC — combined 29/100, moisture 30, movement 26, water table 30Hertford County, NC — combined 39/100, moisture 42, movement 30, water table 46Hoke County, NC — combined 48/100, moisture 42, movement 44, water table 66Hyde County, NC — combined 45/100, moisture 41, movement 34, water table 66Iredell County, NC — combined 35/100, moisture 38, movement 44, water table 16Jackson County, NC — combined 26/100, moisture 31, movement 26, water table 16Johnston County, NC — combined 51/100, moisture 44, movement 39, water table 82Jones County, NC — combined 40/100, moisture 43, movement 32, water table 46Lee County, NC — combined 46/100, moisture 43, movement 37, water table 66Lenoir County, NC — combined 40/100, moisture 43, movement 30, water table 46Lincoln County, NC — combined 43/100, moisture 36, movement 61, water table 30Macon County, NC — combined 36/100, moisture 32, movement 33, water table 46Madison County, NC — combined 30/100, moisture 30, movement 29, water table 30Martin County, NC — combined 43/100, moisture 40, movement 30, water table 66McDowell County, NC — combined 30/100, moisture 30, movement 18, water table 46Mecklenburg County, NC — combined 33/100, moisture 37, movement 30, water table 30Mitchell County, NC — combined 34/100, moisture 30, movement 32, water table 46Montgomery County, NC — combined 47/100, moisture 38, movement 61, water table 46Moore County, NC — combined 53/100, moisture 42, movement 47, water table 82Nash County, NC — combined 43/100, moisture 40, movement 19, water table 82New Hanover County, NC — combined 47/100, moisture 42, movement 39, water table 66Northampton County, NC — combined 35/100, moisture 43, movement 17, water table 46Onslow County, NC — combined 42/100, moisture 41, movement 40, water table 46Orange County, NC — combined 42/100, moisture 40, movement 43, water table 46Pamlico County, NC — combined 36/100, moisture 43, movement 20, water table 46Pasquotank County, NC — combined 47/100, moisture 43, movement 40, water table 66Pender County, NC — combined 43/100, moisture 44, movement 24, water table 66Perquimans County, NC — combined 45/100, moisture 43, movement 33, water table 66Person County, NC — combined 40/100, moisture 41, movement 21, water table 66Pitt County, NC — combined 38/100, moisture 41, movement 29, water table 46Polk County, NC — combined 35/100, moisture 31, movement 34, water table 46Randolph County, NC — combined 46/100, moisture 43, movement 36, water table 66Richmond County, NC — combined 45/100, moisture 42, movement 48, water table 46Robeson County, NC — combined 52/100, moisture 40, movement 47, water table 82Rockingham County, NC — combined 47/100, moisture 42, movement 30, water table 82Rowan County, NC — combined 38/100, moisture 34, movement 48, water table 30Rutherford County, NC — combined 38/100, moisture 38, movement 33, water table 46Sampson County, NC — combined 37/100, moisture 43, movement 22, water table 46Scotland County, NC — combined 53/100, moisture 43, movement 46, water table 82Stanly County, NC — combined 38/100, moisture 37, movement 44, water table 30Stokes County, NC — combined 40/100, moisture 34, movement 57, water table 30Surry County, NC — combined 43/100, moisture 35, movement 63, water table 30Swain County, NC — combined 27/100, moisture 32, movement 17, water table 30Transylvania County, NC — combined 28/100, moisture 34, movement 18, water table 30Tyrrell County, NC — combined 46/100, moisture 42, movement 36, water table 66Union County, NC — combined 37/100, moisture 35, movement 32, water table 46Vance County, NC — combined 45/100, moisture 44, movement 46, water table 46Wake County, NC — combined 46/100, moisture 40, movement 41, water table 66Warren County, NC — combined 43/100, moisture 43, movement 25, water table 66Washington County, NC — combined 45/100, moisture 41, movement 24, water table 82Watauga County, NC — combined 42/100, moisture 35, movement 61, water table 30Wayne County, NC — combined 41/100, moisture 41, movement 22, water table 66Wilkes County, NC — combined 42/100, moisture 36, movement 48, water table 46Wilson County, NC — combined 43/100, moisture 41, movement 45, water table 46Yadkin County, NC — combined 39/100, moisture 39, movement 44, water table 30Yancey County, NC — combined 32/100, moisture 31, movement 36, 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
Moore County53424782Southern Atlantic Coastal Plain
Scotland County53434682Southern Atlantic Coastal Plain
Robeson County52404782Southern Atlantic Coastal Plain
Johnston County51443982Southern Atlantic Coastal Plain
Beaufort County50434766Southern Atlantic Coastal Plain
Bertie County50423782Southern Atlantic Coastal Plain
Caswell County50443482Southern Atlantic Coastal Plain
Currituck County49443382Southern Atlantic Coastal Plain
Forsyth County48386446Piedmont
Hoke County48424466Southern Atlantic Coastal Plain
Gates County47414366Southern Atlantic Coastal Plain
Montgomery County47386146Piedmont
New Hanover County47423966Southern Atlantic Coastal Plain
Pasquotank County47434066Southern Atlantic Coastal Plain
Rockingham County47423082Southern Atlantic Coastal Plain
Columbus County46422582Southern Atlantic Coastal Plain
Lee County46433766Southern Atlantic Coastal Plain
Randolph County46433666Southern Atlantic Coastal Plain
Tyrrell County46423666Southern Atlantic Coastal Plain
Wake County46404166Southern Atlantic Coastal Plain
Chatham County45422482Southern Atlantic Coastal Plain
Chowan County45444746Southern Atlantic Coastal Plain
Cleveland County45386530Piedmont
Duplin County45414946Southern Atlantic Coastal Plain
Granville County45434846Southern Atlantic Coastal Plain
Hyde County45413466Southern Atlantic Coastal Plain
Perquimans County45433366Southern Atlantic Coastal Plain
Richmond County45424846Southern Atlantic Coastal Plain
Vance County45444646Southern Atlantic Coastal Plain
Washington County45412482Southern Atlantic Coastal Plain
Craven County44444446Southern Atlantic Coastal Plain
Ashe County43374846Piedmont
Bladen County43422866Southern Atlantic Coastal Plain
Brunswick County43411782Southern Atlantic Coastal Plain
Cumberland County43403266Southern Atlantic Coastal Plain
Durham County43432566Southern Atlantic Coastal Plain
Greene County43403066Southern Atlantic Coastal Plain
Guilford County43365246Piedmont
Lincoln County43366130Piedmont
Martin County43403066Southern Atlantic Coastal Plain
Nash County43401982Southern Atlantic Coastal Plain
Pender County43442466Southern Atlantic Coastal Plain
Surry County43356330Piedmont
Warren County43432566Southern Atlantic Coastal Plain
Wilson County43414546Southern Atlantic Coastal Plain
Onslow County42414046Southern Atlantic Coastal Plain
Orange County42404346Southern Atlantic Coastal Plain
Watauga County42356130Piedmont
Wilkes County42364846Piedmont
Franklin County41402366Southern Atlantic Coastal Plain
Halifax County41433446Southern Atlantic Coastal Plain
Wayne County41412266Southern Atlantic Coastal Plain
Alamance County40441766Southern Atlantic Coastal Plain
Cabarrus County40364146Piedmont
Harnett County40431766Southern Atlantic Coastal Plain
Jones County40433246Southern Atlantic Coastal Plain
Lenoir County40433046Southern Atlantic Coastal Plain
Person County40412166Southern Atlantic Coastal Plain
Stokes County40345730Piedmont
Alleghany County39383646Piedmont
Dare County39442646Southern Atlantic Coastal Plain
Davidson County39363846Piedmont
Hertford County39423046Southern Atlantic Coastal Plain
Yadkin County39394430Piedmont
Camden County38412946Southern Atlantic Coastal Plain
Pitt County38412946Southern Atlantic Coastal Plain
Rowan County38344830Piedmont
Rutherford County38383346Piedmont
Stanly County38374430Piedmont
Alexander County37345716Piedmont
Carteret County37442046Southern Atlantic Coastal Plain
Cherokee County37323946Blue Ridge Mountains
Graham County37323946Blue Ridge Mountains
Sampson County37432246Southern Atlantic Coastal Plain
Union County37353246Piedmont
Anson County36364130Piedmont
Caldwell County36354330Piedmont
Edgecombe County36412246Southern Atlantic Coastal Plain
Macon County36323346Blue Ridge Mountains
Pamlico County36432046Southern Atlantic Coastal Plain
Iredell County35384416Piedmont
Northampton County35431746Southern Atlantic Coastal Plain
Polk County35313446Blue Ridge Mountains
Avery County34383030Piedmont
Catawba County34354516Piedmont
Gaston County34384116Piedmont
Mitchell County34303246Blue Ridge Mountains
Burke County33343430Piedmont
Mecklenburg County33373030Piedmont
Yancey County32313630Blue Ridge Mountains
Haywood County31313330Blue Ridge Mountains
Davie County30383016Piedmont
Madison County30302930Blue Ridge Mountains
McDowell County30301846Blue Ridge Mountains
Henderson County29302630Blue Ridge Mountains
Clay County28342916Blue Ridge Mountains
Transylvania County28341830Blue Ridge Mountains
Swain County27321730Blue Ridge Mountains
Jackson County26312616Blue Ridge Mountains
Buncombe County25332016Blue Ridge Mountains

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

The physiographic regions inside North Carolina

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

Southern Atlantic Coastal Plain

Low, flat and wet. Groundwater sits close to the surface for much of the year, which is why houses here sit on slabs or piers rather than over basements. Where clays are present they are moderately expansive; where sand dominates, the risk is moisture, not movement.

57 counties: Alamance County, Beaufort County, Bertie County, Bladen County, Brunswick County, Camden County, Carteret County, Caswell County, Chatham County, Chowan County, Columbus County, Craven County, Cumberland County, Currituck County, Dare County, Duplin County, Durham County, Edgecombe County, Franklin County, Gates County, Granville County, Greene County, Halifax County, Harnett County, Hertford County, Hoke County, Hyde County, Johnston County, Jones County, Lee County, Lenoir County, Martin County, Moore County, Nash County, New Hanover County, Northampton County, Onslow County, Orange County, Pamlico County, Pasquotank County, Pender County, Perquimans County, Person County, Pitt County, Randolph County, Richmond County, Robeson County, Rockingham County, Sampson County, Scotland County, Tyrrell County, Vance County, Wake County, Warren County, Washington County, Wayne County, Wilson 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.

28 counties: Alexander County, Alleghany County, Anson County, Ashe County, Avery County, Burke County, Cabarrus County, Caldwell County, Catawba County, Cleveland County, Davidson County, Davie County, Forsyth County, Gaston County, Guilford County, Iredell County, Lincoln County, Mecklenburg County, Montgomery County, Rowan County, Rutherford County, Stanly County, Stokes County, Surry County, Union County, Watauga County, Wilkes County, Yadkin County

Blue Ridge Mountains

Steep ground with deep weathering. Volume change is low, but slope stability is not: colluvium on a mountainside can creep, and debris flows during hurricane rainfall are a documented hazard. A house benched into a slope collects water behind its uphill wall.

15 counties: Buncombe County, Cherokee County, Clay County, Graham County, Haywood County, Henderson County, Jackson County, Macon County, Madison County, McDowell County, Mitchell County, Polk County, Swain County, Transylvania County, Yancey County

Page data updated