Soil series profile
Chelsea soil series
Chelsea is a excessively drained soil with a loamy fine sand surface, mapped on 353,790 acres in 108 counties across 6 states. Hydrologic group A.
- Drainage class
- Excessively drained 89% of mapped acres
- Hydrologic group
- A >99% of mapped acres
- Typical topsoil pH
- 6.1 slightly acidic · range 5.7–6.5
- Mapped area
- 354k acres in 108 counties, 6 states
Typical Chelsea profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–9 in (Ap) | Loamy fine sand | 5.7 | 6% | 82% | 1% |
| 9–29 in (E) | Fine sand | 6.0 | 2% | 95% | 0.2% |
| 29–80 in (E and Bt) | Fine sand | 6.1 | 3% | 95% | 0.1% |
What this means
What Chelsea soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Chelsea soils is slightly acidic: pH 6.1 (most land between 5.7 and 6.5), the range most vegetables, flowers and lawn grasses prefer.
Sandy topsoil covers >99% of mapped Chelsea acres. 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 loamy fine sand (61% of mapped Chelsea acres).
96% of mapped Chelsea acres is excessively or somewhat excessively drained: water moves through fast, so gardens need more frequent watering in dry spells.
For lawns and yards
>99% of mapped acres is in hydrologic group A, where water soaks in fast. Lawns there dry out quickly; deeper, less frequent watering and organic matter help.
For a septic system
For conventional septic absorption fields, NRCS rates >99% of the acres in mapped Chelsea 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 Chelsea soil is found
Mapped acres
Chelsea is mapped in Michigan, Iowa, Indiana, Wisconsin, Illinois and Minnesota. The 60 counties with the most Chelsea acres:
| County | Acres | Share of county land |
|---|---|---|
| Allegan County, MI | 48,814 | 9.2% |
| Kent County, MI | 33,973 | 6.2% |
| LaPorte County, IN | 14,622 | 3.8% |
| Linn County, IA | 14,595 | 3.2% |
| White County, IN | 14,515 | 4.5% |
| Lapeer County, MI | 10,867 | 2.6% |
| Iroquois County, IL | 9,826 | 1.4% |
| Johnson County, IA | 9,613 | 2.5% |
| Osceola County, MI | 8,708 | 2.4% |
| Gladwin County, MI | 8,453 | 2.6% |
| Delaware County, IA | 8,006 | 2.2% |
| Jones County, IA | 7,319 | 2.0% |
| Benton County, IA | 7,191 | 1.6% |
| Trempealeau County, WI | 7,126 | 1.5% |
| Tuscola County, MI | 6,638 | 1.3% |
| Kankakee County, IL | 6,096 | 1.4% |
| Cass County, IN | 6,085 | 2.3% |
| Muscatine County, IA | 5,908 | 2.1% |
| Ionia County, MI | 5,431 | 1.5% |
| Buchanan County, IA | 5,064 | 1.4% |
| Pulaski County, IN | 4,929 | 1.8% |
| LaGrange County, IN | 4,759 | 2.0% |
| La Crosse County, WI | 4,737 | 1.6% |
| Jackson County, IA | 4,376 | 1.1% |
| St. Clair County, MI | 3,986 | 0.8% |
| Dubuque County, IA | 3,885 | 1.0% |
| Goodhue County, MN | 3,729 | 0.8% |
| Cedar County, IA | 3,593 | 1.0% |
| Clayton County, IA | 3,589 | 0.7% |
| Allamakee County, IA | 3,295 | 0.8% |
| Tama County, IA | 3,098 | 0.7% |
| Clinton County, IA | 3,048 | 0.7% |
| Iowa County, IA | 2,801 | 0.8% |
| Louisa County, IA | 2,515 | 1.0% |
| Jasper County, IA | 2,479 | 0.5% |
| Pepin County, WI | 2,283 | 1.5% |
| Black Hawk County, IA | 2,281 | 0.6% |
| Iowa County, WI | 2,203 | 0.5% |
| Parke County, IN | 2,011 | 0.7% |
| Oceana County, MI | 1,901 | 0.6% |
| Mahaska County, IA | 1,851 | 0.5% |
| Richland County, WI | 1,848 | 0.5% |
| Winnebago County, IL | 1,844 | 0.6% |
| Columbia County, WI | 1,829 | 0.4% |
| Jefferson County, WI | 1,754 | 0.5% |
| Bremer County, IA | 1,685 | 0.6% |
| Noble County, IN | 1,603 | 0.6% |
| Jasper County, IN | 1,495 | 0.4% |
| Miami County, IN | 1,448 | 0.6% |
| Henry County, IA | 1,445 | 0.5% |
| Dunn County, WI | 1,354 | 0.2% |
| Steuben County, IN | 1,344 | 0.7% |
| Lee County, IA | 1,311 | 0.4% |
| Grant County, WI | 1,285 | 0.2% |
| Fillmore County, MN | 1,280 | 0.2% |
| Crawford County, WI | 1,230 | 0.3% |
| Knox County, IN | 1,212 | 0.4% |
| Buffalo County, WI | 1,153 | 0.3% |
| Keokuk County, IA | 1,125 | 0.3% |
| Porter County, IN | 1,108 | 0.4% |
Septic absorption fields
NRCS rating, share of Chelsea acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 99.8% |
| Not rated | 0.2% |
Drainage, water table and flooding
Share of Chelsea acres
- Depth to seasonal high water table
- About 5.8 feet (69 in) (median where reported).
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 3–16% (median 7%).
- Topsoil organic matter
- Median 1%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 88.9% |
| Somewhat excessively drained | 6.7% |
| Well drained | 4.2% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
| Not rated | 0.2% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 99.8% |
| B: moderate infiltration | 0.0% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| 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% |
| Not rated | 0.2% |
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 Chelsea (component kind "Series") in SSURGO: 353,790 acres.
- Method
- Shares are by mapped acres of Chelsea components. The profile comes from the single largest Chelsea component. Full methodology.