County soil summary
Soil types in Anoka County, Minnesota
The most widespread soils are Zimmerman, Rifle and Isanti; the most common drainage class is very poorly drained (33% of the land), and typical topsoil pH is 6.0.
- Well or moderately well drained
- 43% of land · state 41%
- Typical topsoil pH
- 6.0 moderately acidic · state 6.5
- Septic fields very limited
- 86% of land · state 91%
- Subject to flooding
- 2% of land, any frequency · state 4%
Most common soils in Anoka County
Share of mapped land
A county is a patchwork of many soils. These 8 cover 63% of the mapped land; 50 named soil series are mapped here in all.
| Soil | Share of land | Drainage | Topsoil pH |
|---|---|---|---|
| Zimmerman | 19.4% | Somewhat excessively drained | 6.0 |
| Rifle | 12.8% | Very poorly drained | Not reported |
| Isanti | 7.9% | Very poorly drained | 5.8 |
| Nymore | 5.6% | Excessively drained | 5.8 |
| Lino | 5.4% | Somewhat poorly drained | 5.6 |
| Sartell | 4.4% | Excessively drained | 5.6 |
| Markey | 3.9% | Very poorly drained | 6.0 |
| Hubbard | 3.6% | Excessively drained | 6.0 |
What this means
What the soils in Anoka County mean for gardens, lawns and septic systems
For your garden
Typical topsoil in Anoka County is moderately acidic: pH 6.0 (most land between 5.5 and 6.3). Many vegetables grow well here, and some gardens benefit from a little lime. Test before adding any.
Sandy topsoil covers 58% of the land. It drains fast and warms early in spring, but dries out and loses nutrients quickly: mulch, compost and steady watering help. The most common surface texture is fine sand (27% of the land).
45% of the land is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.
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 45% 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 86% of the land in Anoka County very limited, 3% somewhat limited and 0% not limited (11% not rated, such as urban land, pits or water).
Statewide, 91% of the land is very limited, so Anoka County is less 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 very poorly drained (33%). 43% of the land is moderately well drained or better, compared with 41% across Minnesota.
Show as a table
| Category | Anoka County | Minnesota |
|---|---|---|
| Excessively drained | 14.9% | 3.1% |
| Somewhat excessively drained | 19.5% | 3.9% |
| Well drained | 5.9% | 20.3% |
| Moderately well drained | 3.0% | 13.7% |
| Somewhat poorly drained | 9.7% | 12.3% |
| Poorly drained | 2.9% | 20.7% |
| Very poorly drained | 32.7% | 22.1% |
| Not rated | 11.4% | 4.1% |
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 | Anoka County | Minnesota |
|---|---|---|
| Not limited | 0.0% | 0.0% |
| Somewhat limited | 2.6% | 4.4% |
| Very limited | 86.0% | 91.3% |
| Not rated | 11.4% | 4.3% |
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 | Anoka County | Minnesota |
|---|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 37.9% | 9.5% |
| B: moderate infiltration | 3.3% | 12.3% |
| C: slow infiltration | 2.1% | 16.9% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% | 4.4% |
| A/D: D as is, A if drained | 41.4% | 13.9% |
| B/D: D as is, B if drained | 3.5% | 14.0% |
| C/D: D as is, C if drained | 0.2% | 24.7% |
| Not rated | 11.4% | 4.3% |
Flooding
Show as a table
| Category | Anoka County | Minnesota |
|---|---|---|
| No flooding | 90.6% | 92.4% |
| Rare or very rare | 0.2% | 0.2% |
| Occasional | 0.0% | 1.3% |
| Frequent or very frequent | 1.3% | 2.4% |
| Not reported | 7.8% | 3.7% |
Seasonal high water table
Show as a table
| Category | Anoka County | Minnesota |
|---|---|---|
| Within 18 inches at some time of year | 45.2% | 52.0% |
| 18 inches to 3.3 feet | 3.0% | 15.0% |
| Deeper than 3.3 feet or none reported | 44.0% | 29.6% |
| Not reported | 7.8% | 3.3% |
Topsoil pH and texture
First mineral layer of each soil
Typical topsoil pH is 6.0 (moderately acidic); 80% of rated land falls between 5.5 and 6.3. Median topsoil organic matter is 2.5%.
Show as a table
| Category | Anoka County | Minnesota |
|---|---|---|
| Strongly acidic (below 5.5) | 0.0% | 7.0% |
| Moderately to slightly acidic (5.5–6.4) | 59.9% | 27.3% |
| Near neutral (6.5–7.3) | 5.0% | 32.0% |
| Alkaline (7.4 and up) | 1.3% | 15.2% |
| Not reported | 33.8% | 18.6% |
Texture
Show as a table
| Category | Anoka County | Minnesota |
|---|---|---|
| Sandy | 57.8% | 11.2% |
| Loamy (loam, silt loam and similar) | 8.4% | 66.1% |
| Clayey (40%+ clay) | 0.0% | 2.2% |
| Organic (muck or peat) | 22.4% | 16.2% |
| Not reported (rock, urban land, etc.) | 11.4% | 4.3% |
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
- Anoka County, Minnesota (FIPS 27003): 272,236 acres of mapped land, 12,864 acres of open water excluded. State comparisons pool all mapped land in Minnesota.
- 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.