Georgia / Screven County
Score 42 · elevated · #8 of 59 in GA
Crawl space moisture in Screven County, GA
Screven County scores elevated because several moderate signals stack up rather than one dominant one. Where a seasonal water table is reported — 86% of acres — it averages 2.2 ft below grade.
- 1Water table 2.2 ft
- 2Wet soils 39%
- 3Moisture score 42
- 4EPA radon zone 3
Reading the Screven County soil survey
The score of 42 combines four parts, each from the USDA survey: wet drainage classes contribute 39.8 points of 100 on their own scale, group D soils 38.1, a shallow water table 57.7, and flooding 20.8; the weights are on the methodology page. The dominant hydrologic group is B (30% of acres): moderate infiltration.
At 2.2 ft the seasonal water table is usually below a crawl-space floor, but the 86% 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.
Screven County against the rest of Georgia
Screven County ranks 8 of 59 Georgia counties, 27 points above the state median of 15. That puts it in the wettest quarter of the state. Statewide, 25% of mapped soil is in the wet drainage classes; here it is 39%, half again the state figure or more. After well drained, the next most common class is poorly drained at 31%.
Flooding. 18% of acres with a flooding class are rated frequent; 4.7% of acres with a flooding class are rated occasional. 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 Screven County by score
Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area GA251; drainage covers 99% of 419,200 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.