Miami-Dade County Area, Florida
The most common soil here is Biscayne, on about 9% of the land. Krome and Perrine come next.
About 3% of the land drains well, and 56% stays wet for long stretches; groundwater comes within two feet of the surface under 46% of it.
USDA rates 69% of the land very limited for a standard septic drain field, and 69% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 16% of the land floods occasionally or more, and bedrock lies within 40 inches under 55% of it.
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 Miami-Dade County Area, Florida, 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 Very poorly drained and the dominant hydrologic group is C/D (varies with drainage). The most common soil order is Entisols — young soils with little profile development, often on floodplains or steep slopes. 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 Miami-Dade County Area, Florida. 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 |
|---|---|---|---|---|---|
| Urban land, 0 to 2 percent slopes | 137K | Not rated | Not rated | ||
| Water | 38K | Not rated | Not rated | ||
| Biscayne marly silt loam-Rock outcrop complex, 0 to 1 percent slopes | 38K | Very poorly drained | C/D | Very limited | Very limited |
| Krome very gravelly marly loam, 0 to 2 percent slopes | 37K | Moderately well drained | D | Very limited | Very limited |
| Shark Valley muck, 0 to 1 percent slopes, frequently flooded | 37K | Very poorly drained | A/D | Very limited | Very limited |
| Udorthents, limestone substratum-Urban land complex, 0 to 2 percent slopes | 33K | Somewhat poorly drained | A | Very limited | Very limited |
| Perrine marly silt loam, frequnetly ponded, 0 to 1 percent slopes | 33K | Very poorly drained | C/D | Very limited | Very limited |
| Rock outcrop-Vizcaya-Biscayne complex, frequently ponded, 0 to 1 percent slopes | 30K | Very poorly drained | Very limited | Very limited | |
| Cooper Town muck, 0 to 1 percent slopes, frequently flooded | 28K | Very poorly drained | A/D | Very limited | Very limited |
| Waters of the Atlantic Ocean | 24K | Not rated | Not rated | ||
| Krome very gravelly marly loam-Urban land complex, 0 to 2 percent slopes | 22K | Moderately well drained | D | Very limited | Very limited |
| Udorthents-Water-Urban land complex, 0 to 60 percent slopes | 20K | Well drained | A | Very limited | Very limited |
| Macks Camp muck, 0 to 1 percent slopes, frequently flooded | 19K | Very poorly drained | A/D | Very limited | Very limited |
| Chekika very gravelly marly loam, 0 to 2 percent slopes | 19K | Somewhat poorly drained | D | Very limited | Very limited |
| Biscayne marly silt loam, frequently ponded, 0 to 1 percent slopes | 15K | Poorly drained | C/D | Very limited | Very limited |
| Biscayne marly silt loam, drained, 0 to 1 percent slopes | 13K | Very poorly drained | C/D | Very limited | Very limited |
| Shark Valley muck, ponded-Urban land complex, 0 to 1 percent slopes | 9K | Very poorly drained | A/D | Very limited | Very limited |
| Lignumvitae marly silt loam, tidal, 0 to 1 percent slopes, very frequently flooded | 9K | Very poorly drained | C/D | Very limited | Very limited |
| Keylargo muck, tidal, 0 to 1 percent slopes, very frequently flooded | 9K | Very poorly drained | A/D | Very limited | Very limited |
| Perrine marly silt loam, drained, 0 to 1 percent slopes | 8K | Very poorly drained | C/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 69% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 69% 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.