County soil summary

Soil types in Prince William County, Virginia

The most widespread soils are Arcola, Buckhall and Manassas; the most common drainage class is well drained (59% of the land), and typical topsoil pH is 5.0.

Mapped soil survey data 184,000 acres of mapped land · 80 named soil series

Well or moderately well drained
77%
of land · state 85%
Typical topsoil pH
5.0
very strongly acidic · state 5.3
Septic fields very limited
77%
of land · state 77%
Subject to flooding
12%
of land, any frequency · state 10%

Most common soils in Prince William County

Share of mapped land

A county is a patchwork of many soils. These 8 cover 38% of the mapped land; 80 named soil series are mapped here in all.

Most common soils in Prince William County by share of mapped land
Soil Share of land Drainage Topsoil pH
Arcola 11.9% Well drained 5.0
Buckhall 5.3% Well drained 5.0
Manassas 3.7% Moderately well drained 5.0
Albano 3.7% Poorly drained 5.3
Urban landLand type, not a soil series 3.7% — —
Waxpool 3.2% Poorly drained 5.5
Gaila 3.0% Well drained 5.8
Dulles 3.0% Somewhat poorly drained 5.3

Drainage and pH for a series are its typical values across all its mapped acres nationwide. A dash means the row is not a soil series.

What this means

What the soils in Prince William County mean for gardens, lawns and septic systems

For your garden

Typical topsoil in Prince William County is very strongly acidic: pH 5.0 (most land between 4.6 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 91% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (43% of the land).

77% of the land is moderately well to excessively drained, which suits most garden plants.

For your lawn and yard

Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.

For a septic system

For conventional septic absorption fields, NRCS rates 77% of the land in Prince William County very limited, 16% somewhat limited and 0% not limited (7% not rated, such as urban land, pits or water).

That is close to the state as a whole (77% 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.

Flooding is mapped on 12% of the land (2% occasional, 5% frequent).

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.

Drainage

How long the soil stays wet

The most common drainage class is well drained (59%). 77% of the land is moderately well drained or better, compared with 85% across Virginia.

Excessively drained 0%
Somewhat excessively drained <1%
Well drained 59%
Moderately well drained 18%
Somewhat poorly drained 5%
Poorly drained 11%
Very poorly drained <1%
Not rated 7%
Natural drainage class, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
Show as a table
Natural drainage class, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
Excessively drained0.0%2.1%
Somewhat excessively drained0.6%4.9%
Well drained59.0%67.8%
Moderately well drained17.9%10.1%
Somewhat poorly drained4.9%3.1%
Poorly drained10.6%7.0%
Very poorly drained0.4%2.0%
Not rated6.7%3.0%

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.

Not limited 0%
Somewhat limited 16%
Very limited 77%
Not rated 7%
Septic tank absorption field rating, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
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Septic tank absorption field rating, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
Not limited0.0%0.1%
Somewhat limited15.9%20.6%
Very limited77.4%76.5%
Not rated6.7%2.8%

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.

A: fast infiltration (mostly sandy or gravelly) 9%
B: moderate infiltration 34%
C: slow infiltration 20%
D: very slow infiltration (clayey, shallow or wet) 20%
A/D: D as is, A if drained <1%
B/D: D as is, B if drained 3%
C/D: D as is, C if drained 8%
Not rated 7%
Hydrologic soil group, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
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Hydrologic soil group, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
A: fast infiltration (mostly sandy or gravelly)8.9%10.8%
B: moderate infiltration33.9%49.0%
C: slow infiltration19.9%15.0%
D: very slow infiltration (clayey, shallow or wet)19.5%10.1%
A/D: D as is, A if drained0.2%0.9%
B/D: D as is, B if drained2.6%6.7%
C/D: D as is, C if drained7.7%4.0%
Not rated7.2%3.5%

Flooding

No flooding 88%
Rare or very rare 5%
Occasional 2%
Frequent or very frequent 5%
Not reported 0%
Most frequent flooding class in any month, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
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Most frequent flooding class in any month, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
No flooding87.9%88.5%
Rare or very rare5.3%1.7%
Occasional1.8%2.1%
Frequent or very frequent4.9%6.5%
Not reported0.0%1.2%

Seasonal high water table

Within 18 inches at some time of year 20%
18 inches to 3.3 feet 14%
Deeper than 3.3 feet or none reported 66%
Not reported 0%
Shallowest depth to a saturated zone in any month, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
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Shallowest depth to a saturated zone in any month, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
Within 18 inches at some time of year19.8%13.0%
18 inches to 3.3 feet13.9%9.8%
Deeper than 3.3 feet or none reported66.3%76.1%
Not reported0.0%1.1%

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 4.6 and 5.3. Median topsoil organic matter is 1.2%.

Strongly acidic (below 5.5) 86%
Moderately to slightly acidic (5.5–6.4) 7%
Near neutral (6.5–7.3) 0%
Alkaline (7.4 and up) 0%
Not reported 7%
Topsoil pH band, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
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Topsoil pH band, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
Strongly acidic (below 5.5)86.0%64.8%
Moderately to slightly acidic (5.5–6.4)7.3%28.5%
Near neutral (6.5–7.3)0.0%3.4%
Alkaline (7.4 and up)0.0%0.4%
Not reported6.7%3.0%

Texture

Sandy 2%
Loamy (loam, silt loam and similar) 91%
Clayey (40%+ clay) 0%
Organic (muck or peat) 0%
Not reported (rock, urban land, etc.) 7%
Topsoil texture group, share of mapped land in Prince William County. Scale 0 to 100% of mapped land.
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Topsoil texture group, share of mapped land in Prince William County.
CategoryPrince William CountyVirginia
Sandy2.0%9.4%
Loamy (loam, silt loam and similar)91.2%86.6%
Clayey (40%+ clay)0.0%0.2%
Organic (muck or peat)0.0%0.8%
Not reported (rock, urban land, etc.)6.7%2.9%

Most common surface textures: silt loam 43% · loam 26% · sandy loam 10% · fine sandy loam 5% · channery silt loam 3%.

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
Prince William County, Virginia (FIPS 51153): 184,092 acres of mapped land, 7,626 acres of open water excluded. State comparisons pool all mapped land in Virginia.
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.

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