HomeOhioLogan CountyDe Graff
De Graff, Ohio
Inside De Graff's city limits, a shallow water table limits basements on 55% of mapped land. Shrink-swell clay limits houses without basements on 5%.
That water-table share is below Logan County's 81%. FEMA's flood data list no flood losses since 2016 in ZIP code 43318 overlapping the city. Of its 726 homes, 75% were built before 1980; the median dates from 1950.
Data as of October 13, 2026 · sources · in Logan County
expansive clay: shrink-swell limits slab homes
high water table: limits basements
flood losses since 2016 in 1 overlapping ZIP
of homes built before 1980
Basement waterproofing in De Graff
Basement waterproofing in De Graff: a shallow water table limits basements on 55% of De Graff's mapped land.
About 700 of De Graff's 726 homes are detached houses.
Soil under De Graff city limits
| Expansive clay (limits slab homes) | 5.4% |
| High water table (limits basements) | 54.5% |
| Septic fields very limited | 90.1% |
| Clay swell (LEP, by area) | 4.6% |
| High-swell land (LEP 6%+) | 1.9% |
| Urban land, not rated | 4.5% |
| Mapped soil | 641 acres |
What the numbers mean here
On 55% of De Graff's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.
USDA rates 90% of the land very limited for septic absorption fields.
Drought in Logan County
0% of Logan County is in drought (D1 or worse) on the October 13, 2026 map. County detail.
Flood losses by ZIP code
FEMA flood records since 2016 in the ZIP codes that overlap De Graff. ZIP areas reach past city limits.
| ZIP | Share of city land | Flood losses | Paid |
|---|---|---|---|
| 43318 | 100% | 0 | $0 |
Homes in De Graff
| Housing units | 726 |
| Median year built | 1950 |
| Built before 1980 | 75% |
| Built 2000 or later | 11% |
| Owner-occupied | 89% |
| Median value, owner-occupied | $183,800 |
| Single-family detached | 92% |
Nearby cities
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Quincy | 3 mi | 7% | 82% |
| Bellefontaine | 9 mi | 7% | 60% |
| West Liberty | 9 mi | 26% | 44% |
| Port Jefferson | 9 mi | 2% | 30% |
| Huntsville | 11 mi | 45% | 83% |
| Russells Point | 11 mi | 67% | 79% |
| Jackson Center | 11 mi | 30% | 99% |
| Lakeview | 12 mi | 82% | 90% |
Sources: USDA SSURGO (August 5, 2026) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · Census ACS 2020-2024. Methods · Data status