Delaware Soil Surveys
The most common soil here is Fallsington, on about 6% of the land: a sandy loam, gritty and crumbly. Rosedale and Hammonton come next.
About 32% of the land drains well, and 30% stays wet for long stretches; groundwater comes within two feet of the surface under 33% of it.
USDA rates 74% of the land very limited for a standard septic drain field, and 46% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 10% of the land floods occasionally or more.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Delaware, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
Delaware has 3 USDA soil survey areas covering a wide range of landscapes and soil conditions. The most common soil order is Ultisols — strongly weathered soils with clay-enriched subsoils, common in warm humid climates, making up roughly 66% of surveyed soils. Entisols — young soils with little profile development, often on floodplains or steep slopes account for another 20%.
In terms of drainage, 36% of Delaware soils are classified as well drained. About 37% of soils have some form of poor drainage, which is important to consider for septic systems and foundations. Drainage class affects everything from septic system design to basement feasibility to garden planning. Use the survey area pages below to see drainage details for specific counties, or look up any address for an exact soil profile.