Soil series profile

Kaiwiki soil series

Kaiwiki is a well drained soil with a highly organic hydrous silty clay loam surface, mapped on 68,293 acres in 1 county in HI. Hydrologic group C.

#4710 by mapped area hydrous Acrudoxic Hydrudands (Andisols)

Drainage class
Well drained
100% of mapped acres
Hydrologic group
C
100% of mapped acres
Typical topsoil pH
5.2
strongly acidic · range 5.2–5.2
Mapped area
68k
acres in 1 county, 1 state

Typical Kaiwiki profile

Texture and pH by depth

Typical Kaiwiki soil profile by depth 0 in 10 in 20 in 30 in 40 in 50 in 0–6 in · A · pH 5.2 · 30% clay Highly organic hydrous silty clay loam 6–60 in · Bw · pH 5.6 · 30% clay Hydrous silty clay loam
Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).
Show as a table
Typical Kaiwiki horizons (representative values)
Depth Texture pH Clay Sand Organic matter
0–6 in (A) Highly organic hydrous silty clay loam 5.2 30% 15% 12%
6–60 in (Bw) Hydrous silty clay loam 5.6 30% 15% 7%

Representative values from the most extensive Kaiwiki map unit (Kaiwiki highly organic hydrous silty clay loam, 6 to 20 percent slopes, survey area HI801). Other map units of this series vary within the series range.

Hands holding dark garden soil
Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Kaiwiki soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Kaiwiki soils is strongly acidic: pH 5.2. Most vegetables and lawn grasses do best around 6.0 to 7.0, so lime is often needed; blueberries, azaleas and rhododendrons like it as it is.

Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Kaiwiki acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is highly organic hydrous silty clay loam (81% of mapped Kaiwiki acres).

100% of mapped Kaiwiki acres is moderately well to excessively drained, which suits most garden plants.

For lawns and yards

On 100% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.

For a septic system

For conventional septic absorption fields, NRCS rates 100% of the acres in mapped Kaiwiki soils very limited, 0% somewhat limited and 0% not limited.

Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.

Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Kaiwiki soil is found

Mapped acres

Kaiwiki is mapped in Hawaii.

Counties with the most mapped Kaiwiki soil
County Acres Share of county land
Hawaii County, HI 68,293 2.6%

Septic absorption fields

NRCS rating, share of Kaiwiki acres

Not limited 0%
Somewhat limited 0%
Very limited 100%
Septic tank absorption field rating across mapped Kaiwiki acres. Scale 0 to 100% of mapped land.
Show as a table
Septic tank absorption field rating across mapped Kaiwiki acres.
CategoryShare of acres
Not limited0.0%
Somewhat limited0.0%
Very limited100.0%

Drainage, water table and flooding

Share of Kaiwiki acres

Depth to seasonal high water table
None reported within about 6.5 feet (median where reported).
Flooding
Not mapped as flooding on most acres.
Slope
Typically 7–12% (median 12%).
Topsoil organic matter
Median 12%.

Drainage class

Excessively drained 0%
Somewhat excessively drained 0%
Well drained 100%
Moderately well drained 0%
Somewhat poorly drained 0%
Poorly drained 0%
Very poorly drained 0%
Drainage class across mapped Kaiwiki acres. Scale 0 to 100% of mapped land.
Show as a table
Drainage class across mapped Kaiwiki acres.
CategoryShare of acres
Excessively drained0.0%
Somewhat excessively drained0.0%
Well drained100.0%
Moderately well drained0.0%
Somewhat poorly drained0.0%
Poorly drained0.0%
Very poorly drained0.0%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%
B: moderate infiltration 0%
C: slow infiltration 100%
D: very slow infiltration (clayey, shallow or wet) 0%
A/D: D as is, A if drained 0%
B/D: D as is, B if drained 0%
C/D: D as is, C if drained 0%
Hydrologic soil group across mapped Kaiwiki acres. Scale 0 to 100% of mapped land.
Show as a table
Hydrologic soil group across mapped Kaiwiki acres.
CategoryShare of acres
A: fast infiltration (mostly sandy or gravelly)0.0%
B: moderate infiltration0.0%
C: slow infiltration100.0%
D: very slow infiltration (clayey, shallow or wet)0.0%
A/D: D as is, A if drained0.0%
B/D: D as is, B if drained0.0%
C/D: D as is, C if drained0.0%

Sources & data dates

Source
USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
Data date
SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
Scope
All map unit components named Kaiwiki (component kind "Series") in SSURGO: 68,293 acres.
Method
Shares are by mapped acres of Kaiwiki components. The profile comes from the single largest Kaiwiki component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Kaiwiki.