Columbia County, Wisconsin
A shallow water table limits basements on 48% of Columbia County's mapped land, a higher share than 64% of US counties. Shrink-swell clay limits houses without basements on 1%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 57 flood losses here since 2016, 54% of them in buildings with basements. 55% of homes were built before 1980, against 50% nationally; the median home dates from 1976.
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 Columbia County
| Expansive clay (limits slab homes) | 0.8% |
| High water table (limits basements) | 47.8% |
| Septic fields very limited | 85.5% |
| Clay swell (LEP, by area) | 2.5% |
| High-swell land (LEP 6%+) | 0.9% |
| Mapped soil | 508,109 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Lapeer | 10% | n/a |
| Plano | 8% | n/a |
| St. Charles | 5% | n/a |
| Houghton | 4% | n/a |
| Plainfield | 4% | 2% |
| Wyocena | 4% | n/a |
How we count · survey areas WI021 (2025-09-10)
What the numbers mean here
On 48% of Columbia 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: 31.00 in, 4.88 in below the 1991-2020 average year of 35.88 in.
USDA rates 85% of the land very limited for septic absorption fields.
Drought
0% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 21 of the last 52 weeks; the most was 17% of its area, in 4 weeks, most recently on the August 18, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 0% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
57 flood losses since 2016, $1.3 million paid. The worst year was 2019, with 26. Foundations of the buildings, where recorded: 54% basements, 25% slabs, 14% crawl spaces, 7% elevated. Median water depth outside the building: 16 in.
| Year | Flood losses |
|---|---|
| 2016 | 5 |
| 2017 | 1 |
| 2018 | 9 |
| 2019 | 26 |
| 2020 | 7 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 1 |
| 2024 | 2 |
| 2025 | 0 |
| 2026 to date | 6 |
Rain
| Average year, 1991-2020 | 35.88 in |
| 12 months to August 2026 | 31.00 in (-4.88) |
| 2025 | 31.03 in (-4.85) |
| Wettest year since 1895 | 2018: 50.16 in |
| Driest year since 1895 | 1958: 18.67 in |
| Days with 1 inch or more, normal at PORTAGE WWTP (7 mi away) | 8.2 |
Homes
| Housing units | 26,880 |
| Median year built | 1976 |
| Built before 1980 | 55% |
| Built 2000 or later | 22% |
| Owner-occupied | 77% |
| Median value, owner-occupied | $283,200 |
| Single-family detached | 77% |
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 |
|---|---|---|---|
| Marquette County, WI | 25 mi | 1% | 41% |
| Green Lake County, WI | 28 mi | 2% | 48% |
| Dane County, WI | 28 mi | 7% | 34% |
| Sauk County, WI | 31 mi | 1% | 26% |
| Dodge County, WI | 32 mi | 7% | 59% |
| Adams County, WI | 41 mi | 2% | 40% |
| Jefferson County, WI | 42 mi | 4% | 57% |
| Waushara County, WI | 44 mi | 5% | 36% |
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