Florida / Okaloosa County

Score 21 · moderate · #67 of 67 in FL

Crawl space moisture in Okaloosa County, FL

Okaloosa County scores moderate: no single wet-soil signal dominates its mapped acres. Where a seasonal water table is reported — 40% of acres — it averages 2.2 ft below grade.

Size venting or encapsulation

1234
  1. 1Water table 2.2 ft
  2. 2Wet soils 25%
  3. 3Moisture score 21
  4. 4EPA radon zone 3
Excessively43%Somewhat excessively8%Well23%Moderately well2%Somewhat poorly9%Poorly9%Very poorly7%
Share of mapped soil acres in Okaloosa County, FL by NRCS drainage class (dominant condition), bars to scale; wetter classes highlighted. Covers 92% of mapped acres.
Dominant drainage
Excessively drained
43% of acres
Group D soils
20%
slow infiltration
Flood-prone acres
17%
any flooding frequency
Ponding
0%
acres where water ponds

Reading the Okaloosa County soil survey

The score of 21 combines four parts, each from the USDA survey: wet drainage classes contribute 22.3 points of 100 on their own scale, group D soils 14.1, a shallow water table 26.6, and flooding 15.5; the weights are on the methodology page. The dominant hydrologic group is A (65% of acres): high infiltration, low runoff (sands, gravels).

65%A8%B7%C2%A/D17%B/D1%C/D
Hydrologic soil groups in Okaloosa 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 2.2 ft the seasonal water table is usually below a crawl-space floor, but the 40% 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.

Okaloosa County against the rest of Florida

Okaloosa County ranks 67 of 67 Florida counties, 41 points below the state median of 62. That places it in the middle range, nationally and for the state. Statewide, 74% of mapped soil is in the wet drainage classes; here it is 25%, below the state figure — the score here comes from flooding and ponding rather than drainage class alone. After excessively drained, the next most common class is well drained at 23%.

Flooding. 13.6% of acres with a flooding class are rated frequent; 3% 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 a moderate county the soil record is mixed rather than uniformly wet, so conditions vary from lot to lot. Where the lot drains, the model-code default — a vented crawl space with 1 sq ft of net vent per 150 sq ft of floor, or 1 per 1500 with a Class I vapor retarder on the ground — is a reasonable starting point; where the sections above point to a shallow water table or flood-prone soil on your lot, plan as for an elevated county. Either way, check the site first: grading that falls away from the foundation, gutters and downspouts that discharge well clear of it, and a ground cover over bare earth. A wet crawl space in a moderate county points to one of those first.

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 Okaloosa County by score

All 67 Florida counties

Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area FL091; drainage covers 92% of 637,000 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.