County soil summary
Soil types in Kennebec County, Maine
The most widespread soils are Woodbridge, Paxton and Lyman; the most common drainage class is well drained (29% of the land), and typical topsoil pH is 4.8.
- Well or moderately well drained
- 73% of land · state 58%
- Typical topsoil pH
- 4.8 very strongly acidic · state 4.6
- Septic fields very limited
- 93% of land · state 96%
- Subject to flooding
- <1% of land, any frequency · state 2%
Most common soils in Kennebec County
Share of mapped land
A county is a patchwork of many soils. These 8 cover 67% of the mapped land; 54 named soil series are mapped here in all.
| Soil | Share of land | Drainage | Topsoil pH |
|---|---|---|---|
| Woodbridge | 14.1% | Moderately well drained | 5.2 |
| Paxton | 12.6% | Well drained | 5.5 |
| Lyman | 10.5% | Somewhat excessively drained | 4.0 |
| Tunbridge | 8.0% | Well drained | 4.8 |
| Scantic | 7.3% | Poorly drained | 6.0 |
| Lamoine | 6.0% | Somewhat poorly drained | 5.7 |
| Ridgebury | 5.4% | Poorly drained | 5.5 |
| Charlton | 3.5% | Well drained | 4.8 |
What this means
What the soils in Kennebec County mean for gardens, lawns and septic systems
For your garden
Typical topsoil in Kennebec County is very strongly acidic: pH 4.8 (most land between 4.0 and 5.7). 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 93% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (50% of the land).
73% of the land is moderately well to excessively drained, which suits most garden plants.
For your lawn and yard
On 85% 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.
A seasonal high water table comes within 18 inches of the surface on 46% 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 93% of the land in Kennebec County very limited, 7% somewhat limited and 0% not limited.
That is close to the state as a whole (96% 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 (29%). 73% of the land is moderately well drained or better, compared with 58% across Maine.
Show as a table
| Category | Kennebec County | Maine |
|---|---|---|
| Excessively drained | 5.2% | 4.0% |
| Somewhat excessively drained | 13.0% | 13.3% |
| Well drained | 29.2% | 19.2% |
| Moderately well drained | 25.6% | 21.5% |
| Somewhat poorly drained | 6.4% | 14.4% |
| Poorly drained | 16.1% | 16.3% |
| Very poorly drained | 4.6% | 10.3% |
| Not rated | 0.0% | 0.9% |
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 | Kennebec County | Maine |
|---|---|---|
| Not limited | 0.0% | 0.0% |
| Somewhat limited | 7.2% | 3.3% |
| Very limited | 92.8% | 96.4% |
| Not rated | 0.0% | 0.3% |
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 | Kennebec County | Maine |
|---|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 4.6% | 8.1% |
| B: moderate infiltration | 9.4% | 5.0% |
| C: slow infiltration | 12.0% | 13.6% |
| D: very slow infiltration (clayey, shallow or wet) | 26.1% | 42.6% |
| A/D: D as is, A if drained | 2.2% | 2.9% |
| B/D: D as is, B if drained | 0.9% | 3.7% |
| C/D: D as is, C if drained | 43.7% | 22.1% |
| Not rated | 1.1% | 1.9% |
Flooding
Show as a table
| Category | Kennebec County | Maine |
|---|---|---|
| No flooding | 99.2% | 97.6% |
| Rare or very rare | 0.0% | 0.1% |
| Occasional | 0.1% | 0.5% |
| Frequent or very frequent | 0.7% | 1.4% |
| Not reported | 0.0% | 0.4% |
Seasonal high water table
Show as a table
| Category | Kennebec County | Maine |
|---|---|---|
| Within 18 inches at some time of year | 46.0% | 46.6% |
| 18 inches to 3.3 feet | 19.1% | 20.0% |
| Deeper than 3.3 feet or none reported | 34.9% | 32.9% |
| Not reported | 0.0% | 0.4% |
Topsoil pH and texture
First mineral layer of each soil
Typical topsoil pH is 4.8 (very strongly acidic); 80% of rated land falls between 4.0 and 5.7. Median topsoil organic matter is 4%.
Show as a table
| Category | Kennebec County | Maine |
|---|---|---|
| Strongly acidic (below 5.5) | 76.9% | 75.3% |
| Moderately to slightly acidic (5.5–6.4) | 18.1% | 7.7% |
| Near neutral (6.5–7.3) | 0.0% | 0.1% |
| Alkaline (7.4 and up) | 0.0% | 0.0% |
| Not reported | 4.9% | 16.9% |
Texture
Show as a table
| Category | Kennebec County | Maine |
|---|---|---|
| Sandy | 2.4% | 3.4% |
| Loamy (loam, silt loam and similar) | 92.5% | 76.6% |
| Clayey (40%+ clay) | 0.0% | 0.0% |
| Organic (muck or peat) | 4.3% | 17.6% |
| Not reported (rock, urban land, etc.) | 0.9% | 2.4% |
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
- Kennebec County, Maine (FIPS 23011): 553,600 acres of mapped land, 55,597 acres of open water excluded. State comparisons pool all mapped land in Maine.
- 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.