Islands of Yap, Federated States of Micronesia
The dominant drainage class is Well 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 Islands of Yap, Federated States of Micronesia.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Rumung-Weloy complex, 12 to 30 percent slopes | 5K | Well drained | D | Very limited | Very limited |
| Ilachetomel peat, 0 to 1 percent slopes, frequently flooded | 3K | Very poorly drained | A/D | Very limited | Very limited |
| Rumung-Weloy complex, 30 to 50 percent slopes | 3K | Well drained | D | Very limited | Very limited |
| Yap silty clay loam, 2 to 6 percent slopes | 2K | Well drained | A | Not limited | Very limited |
| Weloy-Rumung complex, 2 to 12 percent slopes | 1K | Well drained | C | Somewhat limited | Very limited |
| Gitam very gravelly silty clay loam, 2 to 6 percent slopes | 1K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Gitam very gravelly silty clay loam, 6 to 12 percent slopes | 1K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Dechel mucky silt loam, 0 to 2 percent slopes, frequently flooded | 992 | Very poorly drained | C/D | Very limited | Very limited |
| Rumung-Weloy complex, 50 to 75 percent slopes | 967 | Well drained | D | Very limited | Very limited |
| Gagil silty clay loam, 2 to 6 percent slopes | 962 | Well drained | A | Not limited | Very limited |
| Yap silty clay loam, 12 to 30 percent slopes | 779 | Well drained | A | Very limited | Very limited |
| Yap silty clay loam, 6 to 12 percent slopes | 674 | Well drained | A | Somewhat limited | Very limited |
| Gagil silty clay loam, 12 to 30 percent slopes | 671 | Well drained | A | Very limited | Very limited |
| Ngedebus sand, 0 to 4 percent slopes, occasionally flooded | 557 | Somewhat excessively drained | A | Very limited | Very limited |
| Yap silty clay loam, 0 to 2 percent slopes | 502 | Well drained | A | Not limited | Very limited |
| Sonahnpil variant extremely gravelly silt loam, 0 to 4 percent slopes, occasionally flooded | 455 | Somewhat poorly drained | C | Very limited | Very limited |
| Gagil silty clay loam, 6 to 12 percent slopes | 447 | Well drained | A | Somewhat limited | Very limited |
| Dublon taxadjunct sandy clay loam, 0 to 4 percent slopes, occasionally flooded | 385 | Somewhat poorly drained | C/D | Very limited | Very limited |
| Gagil extremely gravelly loam, 2 to 12 percent slopes | 360 | Well drained | A | Not limited | Very limited |
| Gagil silty clay loam, 30 to 50 percent slopes | 265 | Well drained | A | Very limited | Very limited |
What This Means
Building & Foundations
About 74% 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 100% 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
Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.