County soil summary

Soil types in Madera County, California

The most widespread soils are Ahwahnee, Vista and Cometa; the most common drainage class is well drained (45% of the land), and typical topsoil pH is 6.5.

Mapped soil survey data 971,000 acres of mapped land · 65 named soil series

Well or moderately well drained
71%
of land · state 81%
Typical topsoil pH
6.5
slightly acidic · state 6.7
Septic fields very limited
74%
of land · state 79%
Subject to flooding
23%
of land, any frequency · state 11%

Most common soils in Madera County

Share of mapped land

A county is a patchwork of many soils. These 8 cover 40% of the mapped land; 65 named soil series are mapped here in all.

Most common soils in Madera County by share of mapped land
Soil Share of land Drainage Topsoil pH
Ahwahnee 8.8% Well drained 6.1
San JoaquinGeneral soil group, not a named series 6.9% — —
Vista 6.2% Well drained 6.7
Cometa 4.4% Well drained 6.1
Hanford 3.8% Well drained 6.7
Coarsegold 3.3% Well drained 6.5
Rock outcropLand type, not a soil series 3.3% — —
Grangeville 3.2% Somewhat poorly drained 7.5

Drainage and pH for a series are its typical values across all its mapped acres nationwide. A dash means the row is not a soil series.

What this means

What the soils in Madera County mean for gardens, lawns and septic systems

For your garden

Typical topsoil in Madera County is slightly acidic: pH 6.5 (most land between 6.1 and 8.5), the range most vegetables, flowers and lawn grasses prefer.

Loamy topsoil (loam, silt loam and similar) covers 60% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (20% of the land).

71% of the land is moderately well to excessively drained, which suits most garden plants.

For your lawn and yard

Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.

For a septic system

For conventional septic absorption fields, NRCS rates 74% of the land in Madera County very limited, 6% somewhat limited and <1% not limited (20% not rated, such as urban land, pits or water).

Statewide, 79% of the land is very limited, so Madera County is less restrictive than typical.

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.

Flooding is mapped on 23% of the land (5% occasional, <1% frequent).

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.

Drainage

How long the soil stays wet

The most common drainage class is well drained (45%). 71% of the land is moderately well drained or better, compared with 81% across California.

Excessively drained 1%
Somewhat excessively drained 8%
Well drained 45%
Moderately well drained 18%
Somewhat poorly drained 8%
Poorly drained <1%
Very poorly drained 0%
Not rated 20%
Natural drainage class, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
Show as a table
Natural drainage class, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
Excessively drained1.2%7.7%
Somewhat excessively drained7.6%17.6%
Well drained45.2%50.7%
Moderately well drained17.5%4.7%
Somewhat poorly drained8.0%2.5%
Poorly drained0.8%2.0%
Very poorly drained0.0%0.7%
Not rated19.9%14.2%

Septic absorption fields

NRCS rating for conventional drain fields

The rating looks at the soil from 24 to 60 inches deep: permeability, depth to a seasonal water table or bedrock, flooding and slope. “Very limited” means at least one feature is unfavorable enough that a conventional field is hard to make work.

Not limited <1%
Somewhat limited 6%
Very limited 74%
Not rated 20%
Septic tank absorption field rating, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
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Septic tank absorption field rating, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
Not limited0.2%4.3%
Somewhat limited5.6%3.6%
Very limited73.9%79.2%
Not rated20.3%12.9%

Rain, runoff and water table

Hydrologic soil group, flooding, seasonal water table

Hydrologic soil group

How fast rain soaks in when the soil is already wet. Group A soaks in fastest, D slowest.

A: fast infiltration (mostly sandy or gravelly) 18%
B: moderate infiltration 16%
C: slow infiltration 21%
D: very slow infiltration (clayey, shallow or wet) 23%
A/D: D as is, A if drained <1%
B/D: D as is, B if drained 3%
C/D: D as is, C if drained <1%
Not rated 18%
Hydrologic soil group, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
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Hydrologic soil group, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
A: fast infiltration (mostly sandy or gravelly)17.8%20.5%
B: moderate infiltration16.4%12.5%
C: slow infiltration21.4%22.7%
D: very slow infiltration (clayey, shallow or wet)22.8%30.3%
A/D: D as is, A if drained0.5%0.3%
B/D: D as is, B if drained2.5%0.3%
C/D: D as is, C if drained0.4%0.9%
Not rated18.3%12.6%

Flooding

No flooding 60%
Rare or very rare 17%
Occasional 5%
Frequent or very frequent <1%
Not reported 18%
Most frequent flooding class in any month, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
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Most frequent flooding class in any month, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
No flooding59.6%77.1%
Rare or very rare17.4%8.2%
Occasional4.8%1.6%
Frequent or very frequent0.5%1.0%
Not reported17.6%12.1%

Seasonal high water table

Within 18 inches at some time of year 11%
18 inches to 3.3 feet <1%
Deeper than 3.3 feet or none reported 72%
Not reported 17%
Shallowest depth to a saturated zone in any month, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
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Shallowest depth to a saturated zone in any month, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
Within 18 inches at some time of year10.7%2.6%
18 inches to 3.3 feet0.3%1.9%
Deeper than 3.3 feet or none reported71.5%86.9%
Not reported17.4%8.6%

Topsoil pH and texture

First mineral layer of each soil

Typical topsoil pH is 6.5 (slightly acidic); 80% of rated land falls between 6.1 and 8.5. Median topsoil organic matter is 1%.

Strongly acidic (below 5.5) 3%
Moderately to slightly acidic (5.5–6.4) 28%
Near neutral (6.5–7.3) 29%
Alkaline (7.4 and up) 18%
Not reported 22%
Topsoil pH band, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
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Topsoil pH band, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
Strongly acidic (below 5.5)3.4%3.1%
Moderately to slightly acidic (5.5–6.4)28.3%22.8%
Near neutral (6.5–7.3)29.3%25.2%
Alkaline (7.4 and up)17.6%30.6%
Not reported21.5%18.2%

Texture

Sandy 18%
Loamy (loam, silt loam and similar) 60%
Clayey (40%+ clay) 1%
Organic (muck or peat) 0%
Not reported (rock, urban land, etc.) 21%
Topsoil texture group, share of mapped land in Madera County. Scale 0 to 100% of mapped land.
Show as a table
Topsoil texture group, share of mapped land in Madera County.
CategoryMadera CountyCalifornia
Sandy17.5%21.3%
Loamy (loam, silt loam and similar)60.4%56.7%
Clayey (40%+ clay)1.0%3.9%
Organic (muck or peat)0.0%0.2%
Not reported (rock, urban land, etc.)21.1%18.0%

Most common surface textures: fine sandy loam 20% · coarse sandy loam 18% · sandy loam 18% · loam 11% · loamy sand 5%.

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
Madera County, California (FIPS 06039): 971,138 acres of mapped land, 5,133 acres of open water excluded. State comparisons pool all mapped land in California.
Method
Shares are by mapped land area: each map unit’s acres in the county times each soil component’s percentage. Open water is excluded. Topsoil values use the first mineral horizon of each component. Full methodology.

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