Mount Rainier National Park, Washington
The most common soil here is Longmire, on about 9% of the land: a ashy sandy loam, gritty and crumbly. Tipsoo and Owyhigh come next.
About 75% of the land drains well, and 11% stays wet for long stretches; groundwater comes within two feet of the surface under 34% of it.
USDA rates all of the land very limited for a standard septic drain field, and all very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 2% of the land floods occasionally or more, and bedrock lies within 40 inches under 76% 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 Mount Rainier National Park, Washington, 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 A (high infiltration, low runoff). The most common soil order is Andisols — soils formed in volcanic ash, very light and porous. 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 Mount Rainier National Park, Washington. 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 |
|---|---|---|---|---|---|
| Glaciers-Rock outcrop complex, 15 to 100 percent slopes | 28K | Very limited | Very limited | ||
| Longmire-Arahustan complex, 35 to 100 percent slopes | 23K | Well drained | A | Very limited | Very limited |
| Tipsoo-Owyhigh complex, 35 to 100 percent slopes | 21K | Well drained | A | Very limited | Very limited |
| Longmire-Arahustan-Vantrump complex, 20 to 65 percent slopes | 11K | Well drained | A | Very limited | Very limited |
| Sluiskin-Owyhigh-Summerland complex, 25 to 100 percent slopes | 11K | Well drained | D | Very limited | Very limited |
| Rubbleland, talus-Rock outcrop complex, 15 to 100 percent slopes | 9K | Somewhat excessively drained | Very limited | Very limited | |
| Tipsoo-Owyhigh-Mysticlake complex, 20 to 65 percent slopes | 9K | Well drained | A | Very limited | Very limited |
| Burroughs-Littletahoma-Tatoosh complex, 15 to 100 percent slopes | 8K | Well drained | A | Very limited | Very limited |
| Longmire-Laughingwater-Vantrump complex, 5 to 65 percent slopes | 7K | Well drained | A/D | Very limited | Very limited |
| Owyhigh-Ipsut-Tipsoo complex, 25 to 100 percent slopes | 7K | Well drained | A | Very limited | Very limited |
| Chenuis-Sarvant complex, 25 to 100 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Tipsoo-Unicornpeak-Mysticlake complex, 10 to 55 percent slopes | 6K | Well drained | A/D | Very limited | Very limited |
| Sarvant-Chenuis-Tatoosh complex, 20 to 100 percent slopes | 6K | Well drained | A | Very limited | Very limited |
| Summerland-Tipsoo complex, 15 to 100 percent slopes | 5K | Well drained | A | Very limited | Very limited |
| Owyhigh-Tipsoo-Ipsut complex, 15 to 65 percent slopes | 5K | Well drained | A | Very limited | Very limited |
| Longmire-Arahustan-Ohanapecosh complex, 15 to 65 percent slopes | 4K | Well drained | A | Very limited | Very limited |
| Flett-Narada complex, 0 to 25 percent slopes | 4K | Somewhat excessively drained | A | Very limited | Very limited |
| Sarvant-Wahpenayo-Mountwow complex, 15 to 100 percent slopes | 4K | Well drained | A | Very limited | Very limited |
| Rubbleland, till-Glacierisland-Wonderland complex, 15 to 100 percent slopes | 4K | Somewhat excessively drained | Very limited | Very limited | |
| Ohanapecosh-Arahustan-Summerland complex, 20 to 100 percent slopes | 4K | Well 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 100% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, 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.