Soil series profile
Sansarc soil series
Sansarc is a well drained soil with a clay surface, mapped on 1,008,570 acres in 29 counties across 2 states. Hydrologic group D.
- Drainage class
- Well drained 100% of mapped acres
- Hydrologic group
- D 100% of mapped acres
- Typical topsoil pH
- 7.6 slightly alkaline · range 7.6–7.6
- Mapped area
- 1.0M acres in 29 counties, 2 states
Typical Sansarc profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–4 in (A) | Clay | 7.6 | 50% | 12% | 2.6% |
| 4–10 in (AC) | Parachannery clay | 7.7 | 59% | 8% | 0.9% |
| 10–14 in (C) | Very parachannery clay | 7.7 | 59% | 8% | 0.7% |
| 14–34 in (Cr) | Bedrock | Not reported | Not reported | Not reported | Not reported |
What this means
What Sansarc soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Sansarc soils is slightly alkaline: pH 7.6. Acid-loving plants such as blueberries and azaleas struggle without amended beds, and some trees and shrubs show iron chlorosis (yellow leaves with green veins).
Clayey topsoil covers 100% of mapped Sansarc acres. Clay holds water and nutrients but drains slowly and compacts if worked wet: add compost, avoid tilling soggy soil and consider raised beds. The most common surface texture is clay (91% of mapped Sansarc acres).
100% of mapped Sansarc 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 100% of the acres in mapped Sansarc soils very limited, 0% somewhat limited and 0% 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.
Where Sansarc soil is found
Mapped acres
Sansarc is mapped in South Dakota and Nebraska.
| County | Acres | Share of county land |
|---|---|---|
| Dewey County, SD | 268,247 | 18.3% |
| Stanley County, SD | 205,698 | 22.1% |
| Lyman County, SD | 114,351 | 11.0% |
| Gregory County, SD | 39,458 | 6.1% |
| Ziebach County, SD | 37,499 | 3.0% |
| Brule County, SD | 34,430 | 4.2% |
| Buffalo County, SD | 34,430 | 4.2% |
| Corson County, SD | 32,833 | 2.1% |
| Jones County, SD | 29,364 | 4.8% |
| Mellette County, SD | 27,929 | 3.4% |
| Charles Mix County, SD | 26,428 | 3.8% |
| Tripp County, SD | 23,342 | 2.3% |
| Boyd County, NE | 22,444 | 6.6% |
| Haakon County, SD | 15,403 | 1.3% |
| Walworth County, SD | 13,348 | 3.0% |
| Knox County, NE | 12,314 | 1.7% |
| Hughes County, SD | 11,484 | 2.5% |
| Campbell County, SD | 11,310 | 2.4% |
| Potter County, SD | 11,213 | 2.0% |
| Keya Paha County, NE | 10,323 | 2.1% |
| Hyde County, SD | 9,228 | 1.7% |
| Holt County, NE | 7,100 | 0.5% |
| Sully County, SD | 4,419 | 0.7% |
| Bon Homme County, SD | 1,442 | 0.4% |
| Jackson County, SD | 1,411 | 0.1% |
| Rock County, NE | 1,398 | 0.2% |
| Todd County, SD | 994 | 0.1% |
| Hand County, SD | 575 | 0.1% |
| Brown County, NE | 156 | 0.0% |
Septic absorption fields
NRCS rating, share of Sansarc acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 100.0% |
Drainage, water table and flooding
Share of Sansarc acres
- Depth to seasonal high water table
- None reported within about 6.5 feet (median where reported).
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 9–20% (median 15%).
- Topsoil organic matter
- Median 2.6%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 100.0% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 0.0% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 100.0% |
| 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 Sansarc (component kind "Series") in SSURGO: 1,008,570 acres.
- Method
- Shares are by mapped acres of Sansarc components. The profile comes from the single largest Sansarc component. Full methodology.