Crawl space moisture in Fulton County, KY

54% of Fulton County's soil falls in hydrologic group D or a dual D group: clays and high water tables that shed water slowly. Where a seasonal water table is reported — 78% of acres — it averages 2 ft below grade.

Size venting or encapsulation

1Water table 2 ft
2Wet soils 45%
3Moisture score 47
4EPA radon zone 3

Share of mapped soil acres in Fulton County, KY by NRCS drainage class (dominant condition), bars to scale; wetter classes highlighted. Covers 88% of mapped acres.

Dominant drainage

Somewhat poorly drained

36% of acres

Group D soils

54%

slow infiltration

Flood-prone acres

40%

any flooding frequency

Ponding

acres where water ponds

Reading the Fulton County soil survey

The score of 47 combines four parts, each from the USDA survey: wet drainage classes contribute 44.5 points of 100 on their own scale, group D soils 47.7, a shallow water table 54.1, and flooding 33.9; the weights are on the methodology page. The dominant hydrologic group is C/D (24% of acres): D when undrained, C when drained.

Hydrologic soil groups in Fulton County by share of acres, columns to scale. Group D and dual groups (x/D) shed water slowly and hold it near the surface.

At 2 ft the seasonal water table is usually below a crawl-space floor, but the 78% of acres that report one are by definition the wettest parts of the county; on those lots, a wet spring can bring water close to the footings.

Fulton County against the rest of Kentucky

Fulton County ranks 1 of 49 Kentucky counties, 32 points above the state median of 15. Only no other county in the state scores higher. Statewide, 6% of mapped soil is in the wet drainage classes; here it is 45%, half again the state figure or more. After somewhat poorly drained, the next most common class is moderately well drained at 34%.

Flooding. 26% of acres with a flooding class are rated frequent; 13.1% of acres with a flooding class are rated occasional; 0.4% of acres with a flooding class are rated rare. That is a large flood-prone share; a crawl space in the floodplain needs flood vents under most local floodplain ordinances, which is a separate rule from R408 and can rule out a fully sealed design.

What it means for a crawl space here

In an elevated county the soil supplies more moisture than average, but a vented crawl space can work if the ground is covered: the code lets vent area drop from 1 sq ft per 150 to 1 per 1500 with a Class I vapor retarder on the ground, which is an admission of how much moisture comes from below. Grading, gutters and a ground cover usually decide whether a crawl space here stays dry before any decision about sealing it.

Radon. EPA radon zone 3. The zone is a county-level prediction; EPA says elevated levels occur in every zone and every home should be tested.

Near Fulton County by score

Henderson County 43 Hopkins County 42 Graves County 39 Carter County 31

All 49 Kentucky counties

Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area KY075; drainage covers 88% of 147,488 mapped acres); EPA Map of Radon Zones, county table (June 2024 JSON); IRC R408.3 Unvented crawl space, as adopted in S.C. Code Regs. 8-1221 (LII). Checked 2026-10-23.