New Jersey / Burlington County
Score 35 · moderate · #7 of 21 in NJ
Crawl space moisture in Burlington County, NJ
Burlington County scores moderate: no single wet-soil signal dominates its mapped acres. Where a seasonal water table is reported — 73% of acres — it averages 2.2 ft below grade.
- 1Water table 2.2 ft
- 2Wet soils 32%
- 3Moisture score 35
- 4EPA radon zone 2
Reading the Burlington County soil survey
The score of 35 combines four parts, each from the USDA survey: wet drainage classes contribute 40.4 points of 100 on their own scale, group D soils 23.4, a shallow water table 48.7, and flooding 11.5; the weights are on the methodology page. The dominant hydrologic group is A (41% of acres): high infiltration, low runoff (sands, gravels).
At 2.2 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.
Burlington County against the rest of New Jersey
Burlington County ranks 7 of 21 New Jersey counties, 5 points above the state median of 30. That places it in the middle range, nationally and for the state. Statewide, 30% of mapped soil is in the wet drainage classes; here it is 32%. After moderately well drained, the next most common class is well drained at 22%.
Flooding. 7.7% of acres with a flooding class are rated frequent; 2.5% of acres with a flooding class are rated occasional; 0% of acres with a flooding class are rated 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 Burlington County by score
Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area NJ005; drainage covers 98% of 524,300 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.