How to find soil data for a site
Use the NRCS Web Soil Survey: draw an area of interest around the site and open the Soil Map tab to see SSURGO map units. For site design the most useful ratings are hydrologic soil group (A to D, for stormwater), drainage class, depth to water table and hydric rating. SSURGO is mapped at roughly 1:12,000 to 1:24,000, so it describes the area, not a specific spot; it doesn't replace a geotechnical report or infiltration test.
Step by step
- Open Web Soil Survey, search the address and draw an Area of Interest around the parcel.
- Soil Map tab: note each map unit symbol and name and how much of the site it covers.
- Soil Data Explorer > Suitabilities and Limitations: run Hydrologic Soil Group, Drainage Class, Depth to Water Table and Hydric Rating.
- Download the report as a PDF for the project file.
What matters for design
| Rating | Why you care |
|---|---|
| Hydrologic soil group (A, B, C, D) | Runoff and infiltration potential. A drains well; D barely infiltrates. Drives stormwater approach. |
| Drainage class | Wet soils limit basements, pavements and plantings. |
| Depth to water table | Affects infiltration facilities, foundations and tree selection. |
| Hydric rating | A wetland indicator (see wetlands). |
Limits
- Map units include other soils (inclusions) that aren't drawn separately.
- Urban areas are often mapped as "Urban land" complexes with little detail, since soils were disturbed.
- For infiltration design or foundations, you'll still need test pits, infiltration tests or a geotechnical report.
Everything here is planning-level public data. Confirm boundaries, topography, wetlands and flood status with a licensed surveyor and the right specialists before design decisions depend on them.
Basesheet does all of this for any US address in about 30 seconds, free, with no account.
Build a base planRelated
- How to check a property for wetlands
- How to check if a property is in a FEMA flood zone
- How to make a site base plan from an address
Updated October 2026.