County soil summary
Soil types in Strafford County, New Hampshire
The most widespread soils are Gloucester, Charlton and Hollis; the most common drainage class is well drained (27% of the land), and typical topsoil pH is 5.1.
- Well or moderately well drained
- 72% of land · state 69%
- Typical topsoil pH
- 5.1 strongly acidic · state 4.8
- Septic fields very limited
- 89% of land · state 79%
- Subject to flooding
- 2% of land, any frequency · state 2%
Most common soils in Strafford County
Share of mapped land
A county is a patchwork of many soils. These 8 cover 63% of the mapped land; 43 named soil series are mapped here in all.
| Soil | Share of land | Drainage | Topsoil pH |
|---|---|---|---|
| Gloucester | 20.5% | Somewhat excessively drained | 4.8 |
| Charlton | 9.2% | Well drained | 4.8 |
| Hollis | 8.9% | Somewhat excessively drained | 5.2 |
| Paxton | 6.8% | Well drained | 5.5 |
| Hinckley | 6.3% | Excessively drained | 4.6 |
| Windsor | 4.1% | Excessively drained | 5.1 |
| Leicester | 3.7% | Poorly drained | 5.3 |
| Not namedGeneral soil group, not a named series | 3.6% | — | — |
What this means
What the soils in Strafford County mean for gardens, lawns and septic systems
For your garden
Typical topsoil in Strafford County is strongly acidic: pH 5.1 (most land between 4.8 and 5.5). 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 72% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (27% of the land).
31% of the land is excessively or somewhat excessively drained: water moves through fast, so gardens need more frequent watering in dry spells.
For your lawn and yard
38% of the land is in hydrologic group A, where water soaks in fast. Lawns there dry out quickly; deeper, less frequent watering and organic matter help.
A seasonal high water table comes within 18 inches of the surface on 24% of the land, often in spring. Basements, sump pumps and lawns in low spots feel it first.
For a septic system
For conventional septic absorption fields, NRCS rates 89% of the land in Strafford County very limited, 4% somewhat limited and 0% not limited (7% not rated, such as urban land, pits or water).
Statewide, 79% of the land is very limited, so Strafford County is more restrictive than typical.
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 (27%). 72% of the land is moderately well drained or better, compared with 69% across New Hampshire.
Show as a table
| Category | Strafford County | New Hampshire |
|---|---|---|
| Excessively drained | 10.6% | 5.2% |
| Somewhat excessively drained | 20.7% | 11.2% |
| Well drained | 27.2% | 37.5% |
| Moderately well drained | 13.1% | 15.0% |
| Somewhat poorly drained | 0.0% | 0.3% |
| Poorly drained | 13.6% | 8.7% |
| Very poorly drained | 5.1% | 5.0% |
| Not rated | 9.7% | 17.1% |
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 | Strafford County | New Hampshire |
|---|---|---|
| Not limited | 0.0% | 0.2% |
| Somewhat limited | 4.1% | 5.3% |
| Very limited | 89.2% | 79.1% |
| Not rated | 6.6% | 15.4% |
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 | Strafford County | New Hampshire |
|---|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 37.8% | 11.7% |
| B: moderate infiltration | 7.2% | 17.2% |
| C: slow infiltration | 9.3% | 24.2% |
| D: very slow infiltration (clayey, shallow or wet) | 13.8% | 13.2% |
| A/D: D as is, A if drained | 4.2% | 4.3% |
| B/D: D as is, B if drained | 7.9% | 3.9% |
| C/D: D as is, C if drained | 9.7% | 8.5% |
| Not rated | 10.2% | 17.0% |
Flooding
Show as a table
| Category | Strafford County | New Hampshire |
|---|---|---|
| No flooding | 92.1% | 83.3% |
| Rare or very rare | 0.0% | 0.0% |
| Occasional | 0.2% | 0.5% |
| Frequent or very frequent | 1.8% | 1.7% |
| Not reported | 5.9% | 14.4% |
Seasonal high water table
Show as a table
| Category | Strafford County | New Hampshire |
|---|---|---|
| Within 18 inches at some time of year | 24.0% | 19.3% |
| 18 inches to 3.3 feet | 16.2% | 15.2% |
| Deeper than 3.3 feet or none reported | 59.7% | 52.2% |
| Not reported | 0.0% | 13.4% |
Topsoil pH and texture
First mineral layer of each soil
Typical topsoil pH is 5.1 (strongly acidic); 80% of rated land falls between 4.8 and 5.5. Median topsoil organic matter is 4.1%.
Show as a table
| Category | Strafford County | New Hampshire |
|---|---|---|
| Strongly acidic (below 5.5) | 65.0% | 70.4% |
| Moderately to slightly acidic (5.5–6.4) | 20.5% | 8.5% |
| Near neutral (6.5–7.3) | 0.0% | 0.2% |
| Alkaline (7.4 and up) | 0.7% | 0.1% |
| Not reported | 13.8% | 20.8% |
Texture
Show as a table
| Category | Strafford County | New Hampshire |
|---|---|---|
| Sandy | 14.9% | 11.6% |
| Loamy (loam, silt loam and similar) | 71.6% | 64.6% |
| Clayey (40%+ clay) | 0.0% | 0.0% |
| Organic (muck or peat) | 4.7% | 6.5% |
| Not reported (rock, urban land, etc.) | 8.8% | 17.3% |
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
- Strafford County, New Hampshire (FIPS 33017): 238,332 acres of mapped land, 6,955 acres of open water excluded. State comparisons pool all mapped land in New Hampshire.
- 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.