New Jersey: basement moisture and foundation risk by county
21 counties, ranked by our combined index. Highest combined risk is Union County (45), lowest is Monmouth County (33). The worst soil for foundation cracks specifically is in Passaic County.
| County | Index | Moisture | Cracks | Water table | Region |
|---|---|---|---|---|---|
| Union County | 45 | 37 | 55 | 46 | Piedmont |
| Atlantic County | 44 | 40 | 34 | 66 | Atlantic coastal plain |
| Cape May County | 44 | 40 | 35 | 66 | Atlantic coastal plain |
| Mercer County | 44 | 42 | 31 | 66 | Atlantic coastal plain |
| Passaic County | 43 | 39 | 58 | 30 | Piedmont |
| Bergen County | 41 | 38 | 42 | 46 | Piedmont |
| Essex County | 41 | 39 | 52 | 30 | Piedmont |
| Middlesex County | 41 | 39 | 41 | 46 | Piedmont |
| Somerset County | 40 | 34 | 44 | 46 | Piedmont |
| Camden County | 39 | 41 | 18 | 66 | Atlantic coastal plain |
| Cumberland County | 39 | 42 | 15 | 66 | Atlantic coastal plain |
| Gloucester County | 38 | 39 | 18 | 66 | Atlantic coastal plain |
| Burlington County | 37 | 42 | 25 | 46 | Atlantic coastal plain |
| Hunterdon County | 37 | 38 | 30 | 46 | Piedmont |
| Ocean County | 37 | 41 | 26 | 46 | Atlantic coastal plain |
| Salem County | 36 | 41 | 21 | 46 | Atlantic coastal plain |
| Sussex County | 36 | 34 | 52 | 16 | Piedmont |
| Warren County | 36 | 39 | 36 | 30 | Piedmont |
| Hudson County | 34 | 38 | 31 | 30 | Piedmont |
| Morris County | 34 | 34 | 48 | 16 | Piedmont |
| Monmouth County | 33 | 39 | 16 | 46 | Atlantic coastal plain |
Values from USDA NRCS SSURGO where available, otherwise our regional model — each county page states which. Methodology.
The physiographic regions inside New Jersey
State lines are political; soil follows geology. These are the distinct ground types inside New Jersey and why each behaves the way it does.
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.
11 counties: Bergen County, Essex County, Hudson County, Hunterdon County, Middlesex County, Morris County, Passaic County, Somerset County, Sussex County, Union County, Warren 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.
10 counties: Atlantic County, Burlington County, Camden County, Cape May County, Cumberland County, Gloucester County, Mercer County, Monmouth County, Ocean County, Salem County
Page data updated