Moultrie County, Illinois
A shallow water table limits basements on 89% of Moultrie County's mapped land, a higher share than 95% of US counties. Shrink-swell clay limits houses without basements on 68%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 1 flood losses here since 2016. 68% of homes were built before 1980, against 50% nationally; the median home dates from 1968.
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 Moultrie County
| Expansive clay (limits slab homes) | 67.8% |
| High water table (limits basements) | 89.2% |
| Septic fields very limited | 96.7% |
| Clay swell (LEP, by area) | 5.5% |
| High-swell land (LEP 6%+) | 45.8% |
| Mapped soil | 220,255 acres |
How we count · survey areas IL139 (2025-08-31)
What the numbers mean here
Clay swell averages a linear extensibility of 5.5% by land area here, and 46% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 68% of the mapped land.
On 89% of Moultrie 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: 40.92 in, 1.03 in above the 1991-2020 average year of 39.89 in.
USDA rates 97% 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 23 of the last 52 weeks; the most was 100% of its area, in 22 weeks, most recently on the March 17, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 21.8% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
1 flood losses since 2016, $0 paid. The worst year was 2018, with 1.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 0 |
| 2018 | 1 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 39.89 in |
| 12 months to August 2026 | 40.92 in (+1.03) |
| 2025 | 28.96 in (-10.93) |
| Wettest year since 1895 | 1927: 56.07 in |
| Driest year since 1895 | 1976: 25.29 in |
| Days with 1 inch or more, normal at SULLIVAN 3S (5 mi away) | 10.6 |
Homes
| Housing units | 6,240 |
| Median year built | 1968 |
| Built before 1980 | 68% |
| Built 2000 or later | 15% |
| Owner-occupied | 76% |
| Median value, owner-occupied | $134,000 |
| Single-family detached | 85% |
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 |
|---|---|---|---|
| Shelby County, IL | 20 mi | 38% | 82% |
| Coles County, IL | 23 mi | 19% | 85% |
| Douglas County, IL | 23 mi | 72% | 96% |
| Macon County, IL | 24 mi | 57% | 88% |
| Piatt County, IL | 26 mi | 57% | 94% |
| Cumberland County, IL | 32 mi | 39% | 84% |
| Christian County, IL | 35 mi | 72% | 86% |
| De Witt County, IL | 40 mi | 69% | 87% |
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