Hill County, Texas
Shrink-swell clay limits houses without basements on 53% of Hill County's mapped land, a higher share than 92% of US counties. A shallow water table limits basements on 2%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 3 flood losses here since 2016. 45% of homes were built before 1980, against 50% nationally; the median home dates from 1984.
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 Hill County
| Expansive clay (limits slab homes) | 53.2% |
| High water table (limits basements) | 2.2% |
| Septic fields very limited | 76.8% |
| Clay swell (LEP, by area) | 8.2% |
| High-swell land (LEP 6%+) | 54.3% |
| Mapped soil | 631,014 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Houston Black | 15% | 91% |
| Heiden | 10% | 80% |
| Ferris | 9% | n/a |
| Tinn | 5% | n/a |
| Eddy | 4% | 0% |
| Normangee | 4% | 72% |
How we count · survey areas TX217 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 8.2% by land area here, and 54% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 53% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 53% of Hill County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 27.76 in, 10.60 in below the 1991-2020 average year of 38.36 in.
USDA rates 77% 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 36 of the last 52 weeks; the most was 100% of its area, in 15 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 | 51.4% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
3 flood losses since 2016, $162,196 paid. The worst year was 2024, with 2.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 2 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 38.36 in |
| 12 months to August 2026 | 27.76 in (-10.60) |
| 2025 | 41.59 in (+3.23) |
| Wettest year since 1895 | 2015: 63.28 in |
| Driest year since 1895 | 1963: 19.76 in |
| Days with 1 inch or more, normal at HILLSBORO (3 mi away) | 11.6 |
Homes
| Housing units | 16,434 |
| Median year built | 1984 |
| Built before 1980 | 45% |
| Built 2000 or later | 28% |
| Owner-occupied | 78% |
| Median value, owner-occupied | $179,200 |
| Single-family detached | 73% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Hill County
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| McLennan County, TX | 30 mi | 56% | under 1% |
| Bosque County, TX | 30 mi | 29% | 1% |
| Johnson County, TX | 31 mi | 51% | 4% |
| Ellis County, TX | 32 mi | 72% | 4% |
| Navarro County, TX | 39 mi | 75% | 8% |
| Somervell County, TX | 41 mi | 13% | 4% |
| Limestone County, TX | 44 mi | 61% | 10% |
| Hood County, TX | 51 mi | 18% | 9% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status