Hancock County, Illinois
A shallow water table limits basements on 72% of Hancock County's mapped land, a higher share than 83% of US counties. Shrink-swell clay limits houses without basements on 48%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 23 flood losses here since 2016. 74% of homes were built before 1980, against 50% nationally; the median home dates from 1964.
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 Hancock County
| Expansive clay (limits slab homes) | 48.2% |
| High water table (limits basements) | 72.3% |
| Septic fields very limited | 81.4% |
| Clay swell (LEP, by area) | 5.1% |
| High-swell land (LEP 6%+) | 42.6% |
| Mapped soil | 521,220 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Ipava | 13% | 100% |
| Virden | 8% | n/a |
| Clarksdale | 8% | n/a |
| Rozetta | 8% | n/a |
| Hickory | 7% | n/a |
| Muscatune | 5% | n/a |
How we count · survey areas IL067 (2025-08-31)
What the numbers mean here
Clay swell averages a linear extensibility of 5.1% by land area here, and 43% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 48% of the mapped land.
On 72% of Hancock 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: 37.66 in, 1.81 in below the 1991-2020 average year of 39.47 in.
USDA rates 81% 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 25 of the last 52 weeks; the most was 100% of its area, in 19 weeks, most recently on the March 31, 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
23 flood losses since 2016, $348,553 paid. The worst year was 2019, with 18.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 0 |
| 2018 | 3 |
| 2019 | 18 |
| 2020 | 0 |
| 2021 | 1 |
| 2022 | 0 |
| 2023 | 1 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 39.47 in |
| 12 months to August 2026 | 37.66 in (-1.81) |
| 2025 | 31.81 in (-7.66) |
| Wettest year since 1895 | 1973: 54.00 in |
| Driest year since 1895 | 1956: 21.03 in |
| Days with 1 inch or more, normal at BENTLEY (5 mi away) | 10.4 |
Homes
| Housing units | 8,938 |
| Median year built | 1964 |
| Built before 1980 | 74% |
| Built 2000 or later | 11% |
| Owner-occupied | 81% |
| Median value, owner-occupied | $113,800 |
| Single-family detached | 83% |
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 |
|---|---|---|---|
| Lee County, IA | 23 mi | 61% | 77% |
| McDonough County, IL | 26 mi | 63% | 70% |
| Adams County, IL | 29 mi | 36% | 70% |
| Clark County, MO | 30 mi | 58% | 78% |
| Henderson County, IL | 31 mi | 13% | 43% |
| Schuyler County, IL | 34 mi | 31% | 46% |
| Des Moines County, IA | 36 mi | 57% | 80% |
| Lewis County, MO | 37 mi | 63% | 81% |
Sources: USDA SSURGO (August 31, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status