St. Croix County, Wisconsin
A shallow water table limits basements on 33% of St. Croix County's mapped land, a higher share than 52% of US counties. Shrink-swell clay limits houses without basements on under 1%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 30 flood losses here since 2016. 33% of homes were built before 1980, against 50% nationally; the median home dates from 1993.
Data as of October 13, 2026 · sources
expansive clay: shrink-swell limits slab homes
high water table: limits basements
in drought, October 13, 2026
of homes built before 1980
Soil under St. Croix County
| Expansive clay (limits slab homes) | 0.3% |
| High water table (limits basements) | 33.3% |
| Septic fields very limited | 82.5% |
| Clay swell (LEP, by area) | 2.6% |
| High-swell land (LEP 6%+) | 1.7% |
| Mapped soil | 470,964 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Santiago | 9% | n/a |
| Sattre | 8% | n/a |
| Freeon | 7% | n/a |
| Amery | 7% | n/a |
| Magnor | 5% | n/a |
| Burkhardt | 4% | n/a |
How we count · survey areas WI109 (2025-09-10)
What the numbers mean here
On 33% of St. Croix County's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.
Rain over the 12 months to August 2026: 25.29 in, 8.43 in below the 1991-2020 average year of 33.72 in.
USDA rates 83% of the land very limited for septic absorption fields.
Drought
100% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 13 of the last 52 weeks; the most was 100% of its area, in 10 weeks, most recently on the October 13, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 100% |
| D2 severe or worse | 100% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
30 flood losses since 2016, $868,558 paid. The worst year was 2020, with 18.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 7 |
| 2020 | 18 |
| 2021 | 0 |
| 2022 | 1 |
| 2023 | 3 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 33.72 in |
| 12 months to August 2026 | 25.29 in (-8.43) |
| 2025 | 32.51 in (-1.21) |
| Wettest year since 1895 | 1975: 43.32 in |
| Driest year since 1895 | 1910: 13.39 in |
| Days with 1 inch or more, normal at BALDWIN (5 mi away) | 6.9 |
Homes
| Housing units | 38,953 |
| Median year built | 1993 |
| Built before 1980 | 33% |
| Built 2000 or later | 40% |
| Owner-occupied | 78% |
| Median value, owner-occupied | $377,700 |
| Single-family detached | 74% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Pierce County, WI | 21 mi | 8% | 39% |
| Washington County, MN | 22 mi | under 1% | 23% |
| Dunn County, WI | 27 mi | 1% | 35% |
| Polk County, WI | 30 mi | under 1% | 33% |
| Ramsey County, MN | 32 mi | 0% | 14% |
| Dakota County, MN | 39 mi | 2% | 23% |
| Chisago County, MN | 40 mi | 1% | 57% |
| Barron County, WI | 40 mi | 0% | 48% |
Sources: USDA SSURGO (September 10, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status