Hawaii Volcanoes National Park, Hawaii

Survey Area HI701• Hawaii

The dominant drainage class is Excessively 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 Hawaii Volcanoes National Park, Hawaii. 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
Lava flows, `a`a, 2 to 20 percent slopes	111K	Excessively drained	A	Very limited	Very limited
Lava flows, pahoehoe, 2 to 20 percent slopes	77K		C	Very limited	Very limited
Lava flows complex, 2 to 20 percent slopes	32K	Excessively drained	A	Very limited	Very limited
Lava flows-Lithic Ustipsamments complex, 2 to 10 percent slopes	19K	Somewhat excessively drained	C	Very limited	Very limited
Kanohina-Lava flows complex, 2 to 10 percent slopes	11K	Well drained	D	Very limited	Very limited
Nakanui-Lava flows complex, 2 to 10 percent slopes	9K	Well drained	D	Very limited	Very limited
Lithic Haplustands-Lava flows complex, 2 to 10 percent slopes	8K	Well drained	D	Very limited	Very limited
Lava flows-Apuki complex, 2 to 20 percent slopes	7K	Somewhat excessively drained	C	Very limited	Very limited
Makaopuhi very paragravelly highly decomposed plant material, 2 to 10 percent slopes	6K	Somewhat poorly drained	D	Very limited	Very limited
Puaulu-Hao complex, 2 to 20 percent slopes	5K	Moderately well drained	D	Not limited	Very limited
Kalapana-Lava flows complex, dry, 2 to 10 percent slopes	5K	Well drained	D	Very limited	Very limited
Puhimau ashy silt loam, 2 to 10 percent slopes	4K	Moderately well drained	D	Very limited	Very limited
Ahiu-Lava flows complex, 2 to 10 percent slopes	4K	Well drained	D	Very limited	Very limited
Alahapa-Lava flows complex, 2 to 10 percent slopes	3K	Somewhat excessively drained	A	Very limited	Very limited
Ihuanu-Lava flows, `a`a complex, 10 to 20 percent slopes, MLRA 160	3K	Well drained	A	Very limited	Very limited
Iwalani-Lava flows complex, 10 to 20 percent slopes	3K	Well drained	D	Very limited	Very limited
Kalapana medial coarse sandy loam, 2 to 10 percent slopes	3K	Well drained	D	Very limited	Very limited
Lava flows association, 40 to 99 percent slopes	3K	Excessively drained	A	Very limited	Very limited
Lava flows-Iwalani complex, 10 to 20 percent slopes	2K	Well drained	C	Very limited	Very limited
Kilauea very gravelly ashy sand, 2 to 10 percent slopes	2K	Excessively drained	D	Not 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.

Andisols

Volcanic ash soils — light, porous, and fertile. Excellent drainage, but low density can complicate foundations.

Histosols

Organic peat and muck soils formed in wetlands. Very poor for building (compressible) and septic. Often in regulated wetlands.

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

What This Means

Building & Foundations

About 97% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, sandy or gravelly soils with low bearing capacity. A geotechnical assessment is recommended before building.

Septic Systems

About 100% of soils are rated "very limited" for septic absorption fields. The well-drained soils may actually drain too fast for standard leach fields, allowing effluent to reach groundwater. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Soils tend to drain very quickly, meaning nutrients and water don't stick around long. Raised beds with amended soil, drip irrigation, and heavy mulching will give the best results. Compost is your best friend here — it improves water retention dramatically.