Maryland / Prince George's County

Score 32 · moderate · #10 of 23 in MD

Crawl space moisture in Prince George's County, MD

Prince George's County scores moderate: no single wet-soil signal dominates its mapped acres. Where a seasonal water table is reported — 73% of acres — it averages 2 ft below grade.

Size venting or encapsulation

1234
  1. 1Water table 2 ft
  2. 2Wet soils 16%
  3. 3Moisture score 32
  4. 4EPA radon zone 2
Excessively1%Somewhat excessively0%Well60%Moderately well24%Somewhat poorly3%Poorly11%Very poorly1%
Share of mapped soil acres in Prince George's County, MD by NRCS drainage class (dominant condition), bars to scale; wetter classes highlighted. Covers 85% of mapped acres.
Dominant drainage
Well drained
60% of acres
Group D soils
30%
slow infiltration
Flood-prone acres
11%
any flooding frequency
Ponding
0%
acres where water ponds

Reading the Prince George's County soil survey

The score of 32 combines four parts, each from the USDA survey: wet drainage classes contribute 22.5 points of 100 on their own scale, group D soils 38, a shallow water table 51.1, and flooding 10.5; the weights are on the methodology page. The dominant hydrologic group is C (43% of acres): slow infiltration (clay layers).

9%A18%B43%C18%D0%A/D5%B/D7%C/D
Hydrologic soil groups in Prince George's 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 73% 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.

Prince George's County against the rest of Maryland

Prince George's County ranks 10 of 23 Maryland counties, 4 points above the state median of 28. That places it in the middle range, nationally and for the state. Statewide, 25% of mapped soil is in the wet drainage classes; here it is 16%, below the state figure — the score here comes from a shallow water table rather than drainage class alone. After well drained, the next most common class is moderately well drained at 24%.

Flooding. 9.1% of acres with a flooding class are rated frequent; 0.8% of acres with a flooding class are rated occasional; 0.1% of acres with a flooding class are rated very rare. Flood-prone soils are a minority here, concentrated along streams; the score mostly reflects what happens between floods.

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

Near Prince George's County by score

All 23 Maryland counties

Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area MD033; drainage covers 85% of 308,033 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.