St. Johns County, Florida
The dominant drainage class is Poorly drained and the dominant hydrologic group is A/D (varies with drainage). This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in St. Johns County, Florida.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Myakka-Myakka, wet, fine sands, 0 to 2 percent slopes | 40K | Poorly drained | A/D | Very limited | Very limited |
| Water | 34K | Not rated | Not rated | ||
| Pomona fine sand | 32K | Poorly drained | B/D | Very limited | Very limited |
| Riviera fine sand, frequently flooded | 27K | Poorly drained | C/D | Very limited | Very limited |
| Tocoi fine sand | 21K | Poorly drained | A/D | Very limited | Very limited |
| Immokalee fine sand | 20K | Poorly drained | A/D | Very limited | Very limited |
| Pellicer silty clay loam, frequently flooded | 17K | Very poorly drained | D | Very limited | Very limited |
| Holopaw fine sand | 17K | Poorly drained | A/D | Very limited | Very limited |
| Riviera fine sand | 16K | Poorly drained | C/D | Very limited | Very limited |
| Smyrna-Smyrna, wet, fine sand, 0 to 2 percent slopes | 11K | Poorly drained | A/D | Very limited | Very limited |
| Terra Ceia muck, 0 to 1 percent slopes, frequently flooded | 10K | Very poorly drained | A/D | Very limited | Very limited |
| St. Johns fine sand | 10K | Poorly drained | B/D | Very limited | Very limited |
| Holopaw fine sand, frequently flooded | 10K | Very poorly drained | A/D | Very limited | Very limited |
| Floridana fine sand, 0 to 2 percent slopes | 9K | Very poorly drained | C/D | Very limited | Very limited |
| Placid fine sand | 9K | Very poorly drained | A/D | Very limited | Very limited |
| Tavares fine sand, 0 to 5 percent slopes | 8K | Moderately well drained | A | Very limited | Very limited |
| Zolfo fine sand | 7K | Somewhat poorly drained | A | Somewhat limited | Very limited |
| Ellzey fine sand | 6K | Poorly drained | B/D | Very limited | Very limited |
| EauGallie fine sand | 6K | Poorly drained | A/D | Very limited | Very limited |
| St. Johns fine sand, depressional | 6K | Very poorly drained | B/D | Very limited | Very limited |
What This Means
Building & Foundations
About 86% of soils are rated "very limited" for dwellings with basements. Specific challenges include poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 89% of soils are rated "very limited" for septic absorption fields. Poorly drained soils can't absorb septic effluent effectively. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Many soils hold water for extended periods. Raised beds are highly recommended to improve drainage for vegetables. Well-adapted native plants and water-loving species will do best in natural conditions.