County soil summary
Soil types in Passaic County, New Jersey
The most widespread soils are Rockaway, Swartswood and Hibernia; the most common drainage class is well drained (34% of the land), and typical topsoil pH is 5.0.
- Well or moderately well drained
- 53% of land · state 62%
- Typical topsoil pH
- 5.0 very strongly acidic · state 5.0
- Septic fields very limited
- 89% of land · state 90%
- Subject to flooding
- 4% of land, any frequency · state 18%
Most common soils in Passaic County
Share of mapped land
A county is a patchwork of many soils. These 8 cover 75% of the mapped land; 38 named soil series are mapped here in all.
| Soil | Share of land | Drainage | Topsoil pH |
|---|---|---|---|
| Rockaway | 22.1% | Well drained | 5.0 |
| Urban landLand type, not a soil series | 15.0% | — | — |
| Rock outcropLand type, not a soil series | 12.7% | — | — |
| Swartswood | 8.3% | Well drained | 4.6 |
| Hibernia | 5.1% | Somewhat poorly drained | 5.0 |
| Riverhead | 5.0% | Well drained | 5.0 |
| Boonton | 3.6% | Well drained | 3.9 |
| RidgeburyGeneral soil group, not a named series | 3.4% | — | — |
What this means
What the soils in Passaic County mean for gardens, lawns and septic systems
For your garden
Typical topsoil in Passaic County is very strongly acidic: pH 5.0 (most land between 4.3 and 5.3). Most vegetables and lawn grasses do best around 6.0 to 7.0, so lime is often needed; blueberries, azaleas and rhododendrons like it as it is.
Loamy topsoil (loam, silt loam and similar) covers 69% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is sandy loam (27% of the land).
For your lawn and yard
On 64% of the land, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.
For a septic system
For conventional septic absorption fields, NRCS rates 89% of the land in Passaic County very limited, 3% somewhat limited and 7% not limited (2% not rated, such as urban land, pits or water).
That is close to the state as a whole (90% very limited).
Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Drainage
How long the soil stays wet
The most common drainage class is well drained (34%). 53% of the land is moderately well drained or better, compared with 62% across New Jersey.
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| Excessively drained | 0.4% | 5.3% |
| Somewhat excessively drained | 0.0% | 4.5% |
| Well drained | 33.6% | 36.6% |
| Moderately well drained | 18.8% | 15.4% |
| Somewhat poorly drained | 8.6% | 5.9% |
| Poorly drained | 7.8% | 9.5% |
| Very poorly drained | 2.7% | 13.6% |
| Not rated | 28.1% | 9.0% |
Septic absorption fields
NRCS rating for conventional drain fields
The rating looks at the soil from 24 to 60 inches deep: permeability, depth to a seasonal water table or bedrock, flooding and slope. “Very limited” means at least one feature is unfavorable enough that a conventional field is hard to make work.
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| Not limited | 6.6% | 1.2% |
| Somewhat limited | 2.6% | 2.9% |
| Very limited | 89.0% | 89.7% |
| Not rated | 1.7% | 6.1% |
Rain, runoff and water table
Hydrologic soil group, flooding, seasonal water table
Hydrologic soil group
How fast rain soaks in when the soil is already wet. Group A soaks in fastest, D slowest.
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 1.8% | 19.9% |
| B: moderate infiltration | 17.5% | 21.5% |
| C: slow infiltration | 36.1% | 17.8% |
| D: very slow infiltration (clayey, shallow or wet) | 24.3% | 10.6% |
| A/D: D as is, A if drained | 1.0% | 15.9% |
| B/D: D as is, B if drained | 1.8% | 4.7% |
| C/D: D as is, C if drained | 1.1% | 2.8% |
| Not rated | 16.4% | 6.8% |
Flooding
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| No flooding | 95.1% | 82.0% |
| Rare or very rare | 0.0% | 2.4% |
| Occasional | 0.0% | 2.1% |
| Frequent or very frequent | 4.1% | 13.4% |
| Not reported | 0.8% | 0.1% |
Seasonal high water table
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| Within 18 inches at some time of year | 19.2% | 32.1% |
| 18 inches to 3.3 feet | 35.1% | 15.8% |
| Deeper than 3.3 feet or none reported | 44.9% | 52.1% |
| Not reported | 0.8% | 0.1% |
Topsoil pH and texture
First mineral layer of each soil
Typical topsoil pH is 5.0 (very strongly acidic); 80% of rated land falls between 4.3 and 5.3. Median topsoil organic matter is 3%.
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| Strongly acidic (below 5.5) | 65.6% | 62.1% |
| Moderately to slightly acidic (5.5–6.4) | 4.2% | 22.5% |
| Near neutral (6.5–7.3) | 0.0% | 2.9% |
| Alkaline (7.4 and up) | 0.0% | 1.1% |
| Not reported | 30.2% | 11.4% |
Texture
Show as a table
| Category | Passaic County | New Jersey |
|---|---|---|
| Sandy | 0.2% | 24.8% |
| Loamy (loam, silt loam and similar) | 69.4% | 53.1% |
| Clayey (40%+ clay) | 0.0% | 0.1% |
| Organic (muck or peat) | 1.7% | 13.7% |
| Not reported (rock, urban land, etc.) | 28.6% | 8.2% |
Sources & data dates
- Source
- USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
- Data date
- SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
- Scope
- Passaic County, New Jersey (FIPS 34031): 118,036 acres of mapped land, 7,964 acres of open water excluded. State comparisons pool all mapped land in New Jersey.
- Method
- Shares are by mapped land area: each map unit’s acres in the county times each soil component’s percentage. Open water is excluded. Topsoil values use the first mineral horizon of each component. Full methodology.