San Benito County, California

Survey Area CA069• California

The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. 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 San Benito County, California. 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
Sedimentary rock land	66K		D	Very limited	Very limited
San Benito clay loam, 30 to 50 percent slopes, eroded, MLRA 15	57K	Well drained	C	Very limited	Very limited
Gaviota rocky loam, 15 to 50 percent slopes, eroded	31K	Somewhat excessively drained	D	Very limited	Very limited
Vallecitos rocky loam, 30 to 50 percent slopes, eroded	31K	Well drained	D	Very limited	Very limited
Sheridan coarse sandy loam, 30 to 75 percent slopes, severely eroded	30K	Well drained	B	Very limited	Very limited
Badland	30K		D	Very limited	Very limited
San Benito clay loam, 15 to 30 percent slopes, eroded, MLRA 15	26K	Well drained	B	Very limited	Very limited
Vallecitos loam, 30 to 50 percent slopes, eroded	24K	Well drained	D	Very limited	Very limited
Kettleman soils, 15 to 50 percent slopes, eroded	23K	Well drained	A	Very limited	Very limited
Cibo cobbly clay, 15 to 75 percent slopes, stony, eroded	20K	Well drained	D	Very limited	Very limited
Diablo clay, 30 to 50 percent slopes, eroded, MLRA 15	19K	Well drained	C	Very limited	Very limited
Borreguero-Sancarlos-Currymountain association, 20 to 65 percent slopes	16K	Well drained	C	Very limited	Very limited
Diablo clay, 15 to 30 percent slopes, eroded, MLRA 15	14K	Well drained	C	Very limited	Very limited
Sheridan coarse sandy loam, 30 to 75 percent slopes, eroded	13K	Well drained	B	Very limited	Very limited
Nacimiento loam, 30 to 75 percent slopes, severely erod ed	12K	Well drained	D	Very limited	Very limited
Gazos clay loam, 30 to 50 percent slopes, eroded	12K	Well drained	C	Very limited	Very limited
Kettleman loam, 15 to 50 percent slopes, eroded	11K	Well drained	B	Very limited	Very limited
Sorrento silty clay loam, 0 to 2 percent slopes, MLRA 14	10K	Well drained	C	Somewhat limited	Very limited
Vallecitos loam, 30 to 50 percent slopes	10K	Well drained	D	Very limited	Very limited
Cieneba gravelly sandy loam, 30 to 75 percent slopes, eroded	9K	Somewhat excessively 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.

Mollisols

Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.

Alfisols

Moderately weathered forest soils with clay-enriched subsoil. Productive for agriculture, generally good for building and septic.

Vertisols

High-clay soils that shrink and swell dramatically. Fertile but challenging for foundations and septic systems.

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. 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.