Indiana / Bartholomew County
Score 44 · elevated · #44 of 92 in IN
Crawl space moisture in Bartholomew County, IN
58% of Bartholomew 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 — 69% of acres — it averages 1 ft below grade, shallow enough to reach a typical crawl-space footing.
- 1Water table 1 ft
- 2Wet soils 44%
- 3Moisture score 44
- 4EPA radon zone 1
Reading the Bartholomew County soil survey
The score of 44 combines four parts, each from the USDA survey: wet drainage classes contribute 42.6 points of 100 on their own scale, group D soils 41.4, a shallow water table 59.1, and flooding 17.3; the weights are on the methodology page. The dominant hydrologic group is B/D (30% of acres): D when undrained, B when drained.
A water table under two feet is the single most important number here. A crawl-space floor is usually 18 to 36 inches below the joists and often below outside grade, so in a wet season groundwater can stand at or above the crawl-space floor across much of Bartholomew County. Venting cannot fix that; it needs drainage — a perimeter drain to daylight or a sump — before any liner goes down.
Bartholomew County against the rest of Indiana
Bartholomew County ranks 44 of 92 Indiana counties, level with the state median of 44. Wetter counties exist in Indiana, but the soil here still sits well above the national middle. Statewide, 47% of mapped soil is in the wet drainage classes; here it is 44%, below the state figure — the score here comes from heavy group D soils rather than drainage class alone. After somewhat poorly drained, the next most common class is well drained at 28%.
Flooding. 13.5% of acres with a flooding class are rated frequent; 5.8% of acres with a flooding class are rated occasional; 1.6% 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. Ponding — water standing at the surface with nowhere to go — affects 1.3% of acres.
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. Bartholomew County is in EPA radon zone 1, the highest predicted potential. A sealed crawl space and a radon system share most of their parts — the liner, the sealed seams, a fan — so if you are encapsulating, test for radon first and design both together. EPA itself says the zone map is not a reason to skip testing in zones 2 and 3.
Near Bartholomew County by score
Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area IN005; drainage covers 94% of 262,329 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.