St. John the Baptist Parish, Louisiana
The dominant drainage class is Very poorly drained and the dominant hydrologic group is D (very slow infiltration, high runoff). 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. John the Baptist Parish, Louisiana.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Water | 82K | Not rated | Not rated | ||
| Barbary soils, 0 to 1 percent slopes, frequently flooded | 68K | Very poorly drained | D | Very limited | Very limited |
| Cancienne silt loam, 0 to 1 percent slopes | 12K | Somewhat poorly drained | C | Somewhat limited | Very limited |
| Maurepas muck, 0 to 1 percent slopes, frequently flooded | 11K | Very poorly drained | A/D | Very limited | Very limited |
| Kenner muck, 0 to 1 percent slopes, very frequently flooded | 8K | Very poorly drained | D | Very limited | Very limited |
| Gramercy silty clay, 0 to 1 percent slopes | 7K | Poorly drained | D | Very limited | Very limited |
| Cancienne and Carville soils, gently undulating, frequently flooded | 7K | Somewhat poorly drained | C | Very limited | Very limited |
| Carville silt loam, 0 to 1 percent slopes | 7K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Schriever clay, 0 to 1 percent slopes, rarely flooded | 5K | Poorly drained | D | Very limited | Very limited |
| Schriever clay, 0 to 1 percent slopes, frequently flooded | 5K | Poorly drained | D | Very limited | Very limited |
| Allemands and Carlin soils, 0 to 0.2 percent slopes, very frequently flooded | 3K | Very poorly drained | A/D | Very limited | Very limited |
| Cancienne silty clay loam, 0 to 1 percent slopes | 2K | Somewhat poorly drained | C | Somewhat limited | Very limited |
| Urban and built up land | 2K | Not rated | Not rated | ||
| Industrial waste pits | 762 | Not rated | Not rated | ||
| Levees-Borrow pits complex, 0 to 25 percent slopes | 618 | Somewhat poorly drained | A/D | Not rated | Not rated |
What This Means
Building & Foundations
About 55% 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 61% 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.