Washington Parish, Louisiana
The most common soil here is Savannah, on about 22% of the land: a fine sandy loam, gritty and crumbly. Ruston and Smithdale come next.
About 52% of the land drains well, and 16% stays wet for long stretches; groundwater comes within two feet of the surface under 57% of it.
USDA rates 78% of the land very limited for a standard septic drain field, and 65% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 25% 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 Washington Parish, Louisiana, 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.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). The most common soil order is Ultisols — strongly weathered soils with clay-enriched subsoils, common in warm humid climates. 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 Washington Parish, Louisiana. Search your address to find the exact soil composition, drainage, and series details at your specific location.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Savannah fine sandy loam, 1 to 3 percent slopes | 79K | Moderately well drained | C/D | Very limited | Very limited |
| Ouachita, Bibb, and Jena soils, frequently flooded | 68K | Well drained | C | Very limited | Very limited |
| Ruston fine sandy loam, 3 to 8 percent slopes | 60K | Well drained | B | Not limited | Somewhat limited |
| Smithdale fine sandy loam, 8 to 12 percent slopes | 37K | Well drained | B | Somewhat limited | Very limited |
| Ruston fine sandy loam, 1 to 3 percent slopes | 27K | Well drained | B | Not limited | Somewhat limited |
| Savannah fine sandy loam, 3 to 8 percent slopes | 26K | Moderately well drained | C/D | Very limited | Very limited |
| Myatt fine sandy loam, frequently flooded | 21K | Poorly drained | B/D | Very limited | Very limited |
| Arkabutla, Rosebloom, and Jena soils, frequently flooded | 16K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Prentiss fine sandy loam, 0 to 1 percent slopes | 14K | Moderately well drained | C | Very limited | Very limited |
| Stough fine sandy loam, 0 to 2 percent slopes | 13K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Cahaba fine sandy loam, 1 to 5 percent slopes | 12K | Well drained | B | Not limited | Very limited |
| Myatt fine sandy loam, 0 to 1 percent slopes | 12K | Poorly drained | B/D | Very limited | Very limited |
| Bassfield sandy loam, 1 to 3 percent slopes | 9K | Well drained | A | Not limited | Very limited |
| Smithdale fine sandy loam, 12 to 20 percent slopes | 8K | Well drained | B | Very limited | Very limited |
| Prentiss fine sandy loam, 1 to 3 percent slopes | 6K | Moderately well drained | C | Very limited | Very limited |
| Tangi silt loam, 1 to 3 percent slopes | 6K | Moderately well drained | C/D | Very limited | Very limited |
| Water | 4K | Not rated | Not rated | ||
| Arat muck | 3K | Very poorly drained | C/D | Very limited | Very limited |
| Pits | 3K | Not rated | Not rated | ||
| Fluker silt loam, 0 to 2 percent slopes | 2K | Somewhat poorly drained | D | Very limited | Very limited |
Soil Orders in This Area
The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.
What This Means
Building & Foundations
About 65% 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 78% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.