Jay County, Indiana
A shallow water table limits basements on 96% of Jay County's mapped land, a higher share than 99% of US counties and the 4th highest of 92 Indiana counties. Shrink-swell clay limits houses without basements on 60%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list no flood losses here since 2016. 73% of homes were built before 1980, against 50% nationally; the median home dates from 1959.
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 Jay County
| Expansive clay (limits slab homes) | 60.1% |
| High water table (limits basements) | 96.5% |
| Septic fields very limited | 97.1% |
| Clay swell (LEP, by area) | 6.0% |
| High-swell land (LEP 6%+) | 38.4% |
| Mapped soil | 245,786 acres |
How we count · survey areas IN075 (2025-09-03)
What the numbers mean here
Clay swell averages a linear extensibility of 6.0% by land area here, and 38% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 60% of the mapped land.
On 96% of Jay 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: 40.91 in, 0.53 in above the 1991-2020 average year of 40.38 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 24 of the last 52 weeks; the most was 100% of its area, in 23 weeks, most recently on the March 24, 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
FEMA's flood data list no flood losses in Jay County since 2016.
Rain
| Average year, 1991-2020 | 40.38 in |
| 12 months to August 2026 | 40.91 in (+0.53) |
| 2025 | 33.74 in (-6.64) |
| Wettest year since 1895 | 1990: 53.28 in |
| Driest year since 1895 | 1963: 24.63 in |
| Days with 1 inch or more, normal at PORTLAND 1 SW (1 mi away) | 8.2 |
Homes
| Housing units | 8,904 |
| Median year built | 1959 |
| Built before 1980 | 73% |
| Built 2000 or later | 10% |
| Owner-occupied | 80% |
| Median value, owner-occupied | $117,500 |
| 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 |
|---|---|---|---|
| Blackford County, IN | 17 mi | 63% | 96% |
| Randolph County, IN | 19 mi | 25% | 94% |
| Mercer County, OH | 21 mi | 37% | 95% |
| Adams County, IN | 22 mi | 45% | 97% |
| Wells County, IN | 24 mi | 55% | 93% |
| Delaware County, IN | 25 mi | 39% | 86% |
| Darke County, OH | 29 mi | 26% | 96% |
| Grant County, IN | 35 mi | 43% | 93% |
Sources: USDA SSURGO (September 3, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status