Soil series profile

Rockaway soil series

Rockaway is a well drained soil with a sandy loam surface, mapped on 109,370 acres in 7 counties in NJ. Hydrologic group C.

#3274 by mapped area coarse-loamy Typic Fragiudults (Ultisols)

Drainage class: Well drained
Hydrologic group: C
Typical topsoil pH: 5.0
Mapped area: 109k

Typical Rockaway profile

Texture and pH by depth

Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).

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Typical Rockaway horizons (representative values)
Depth	Texture	pH	Clay	Sand	Organic matter
0–4 in (A)	Sandy loam	5.0	13%	67%	2%
4–8 in (AB)	Sandy loam	5.0	13%	67%	2%
8–20 in (Bt)	Gravelly sandy loam	5.0	13%	67%	0.25%
20–36 in (Bx)	Gravelly sandy loam	5.0	13%	67%	0.25%
36–40 in (Cx)	Gravelly sandy loam	5.0	13%	67%	0.25%
40–60 in (C)	Gravelly sandy loam	5.0	13%	67%	0%

Representative values from the most extensive Rockaway map unit (Rockaway sandy loam, 8 to 15 percent slopes, very stony, survey area NJ027). Other map units of this series vary within the series range.

Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Rockaway soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Rockaway soils is very strongly acidic: pH 5.0 (most land between 4.8 and 5.0). 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 100% of mapped Rockaway acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is sandy loam (65% of mapped Rockaway acres).

100% of mapped Rockaway acres is moderately well to excessively drained, which suits most garden plants.

For lawns and yards

On 100% of mapped acres, 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 >99% of the acres in mapped Rockaway soils very limited, 0% somewhat limited and <1% not 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.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Rockaway soil is found

Mapped acres

Rockaway is mapped in New Jersey.

Counties with the most mapped Rockaway soil
County	Acres	Share of county land
Morris County, NJ	48,559	16.5%
Passaic County, NJ	26,083	22.1%
Sussex County, NJ	22,704	6.8%
Bergen County, NJ	5,998	4.0%
Warren County, NJ	5,876	2.6%
Essex County, NJ	136	0.2%
Somerset County, NJ	14	0.0%

Septic absorption fields

NRCS rating, share of Rockaway acres

Not limited <1%

Somewhat limited 0%

Very limited >99%

Septic tank absorption field rating across mapped Rockaway acres. Scale 0 to 100% of mapped land.

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Septic tank absorption field rating across mapped Rockaway acres.
Category	Share of acres
Not limited	0.1%
Somewhat limited	0.0%
Very limited	99.9%

Drainage, water table and flooding

Share of Rockaway acres

Depth to seasonal high water table: About 2.5 feet (30 in) (median where reported).
Flooding: Not mapped as flooding on most acres.
Slope: Typically 9–25% (median 12%).
Topsoil organic matter: Median 3%.

Drainage class

Excessively drained 0%

Somewhat excessively drained 0%

Well drained 66%

Moderately well drained 34%

Somewhat poorly drained 0%

Poorly drained 0%

Very poorly drained 0%

Drainage class across mapped Rockaway acres. Scale 0 to 100% of mapped land.

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Drainage class across mapped Rockaway acres.
Category	Share of acres
Excessively drained	0.0%
Somewhat excessively drained	0.0%
Well drained	66.4%
Moderately well drained	33.6%
Somewhat poorly drained	0.0%
Poorly drained	0.0%
Very poorly drained	0.0%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%

B: moderate infiltration 0%

C: slow infiltration 100%

D: very slow infiltration (clayey, shallow or wet) 0%

A/D: D as is, A if drained 0%

B/D: D as is, B if drained 0%

C/D: D as is, C if drained 0%

Hydrologic soil group across mapped Rockaway acres. Scale 0 to 100% of mapped land.

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Hydrologic soil group across mapped Rockaway acres.
Category	Share of acres
A: fast infiltration (mostly sandy or gravelly)	0.0%
B: moderate infiltration	0.0%
C: slow infiltration	100.0%
D: very slow infiltration (clayey, shallow or wet)	0.0%
A/D: D as is, A if drained	0.0%
B/D: D as is, B if drained	0.0%
C/D: D as is, C if drained	0.0%

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: All map unit components named Rockaway (component kind "Series") in SSURGO: 109,370 acres.
Method: Shares are by mapped acres of Rockaway components. The profile comes from the single largest Rockaway component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Rockaway.