County soil summary

Soil types in Bernalillo County, New Mexico

The most widespread soils are Bluepoint, Madurez and Wink; the most common drainage class is well drained (67% of the land), and typical topsoil pH is 8.2.

Mapped soil survey data 749,000 acres of mapped land · 53 named soil series

Well or moderately well drained
90%
of land · state 84%
Typical topsoil pH
8.2
moderately alkaline · state 7.8
Septic fields very limited
71%
of land · state 65%
Subject to flooding
7%
of land, any frequency · state 7%

Most common soils in Bernalillo County

Share of mapped land

A county is a patchwork of many soils. These 8 cover 56% of the mapped land; 53 named soil series are mapped here in all.

Most common soils in Bernalillo County by share of mapped land
Soil Share of land Drainage Topsoil pH
Bluepoint 14.3% Somewhat excessively drained 8.2
Madurez 8.5% Well drained 8.2
Rock outcropLand type, not a soil series 7.4% — —
Wink 6.6% Well drained 8.2
Silver 5.8% Well drained 7.6
Kokan 5.0% Excessively drained 8.2
Penistaja 4.6% Well drained 7.5
Pajarito 3.4% Well drained 7.9

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 Bernalillo County mean for gardens, lawns and septic systems

For your garden

Typical topsoil in Bernalillo County is moderately alkaline: pH 8.2 (most land between 7.5 and 8.2). Acid-loving plants such as blueberries and azaleas struggle without amended beds, and some trees and shrubs show iron chlorosis (yellow leaves with green veins).

Loamy topsoil (loam, silt loam and similar) covers 48% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is loamy fine sand (22% of the land).

90% of the land is moderately well to excessively drained, which suits most garden plants.

For your lawn and yard

33% of the land is in hydrologic group A, where water soaks in fast. Lawns there dry out quickly; deeper, less frequent watering and organic matter help.

For a septic system

For conventional septic absorption fields, NRCS rates 71% of the land in Bernalillo County very limited, 13% somewhat limited and 14% not limited (2% not rated, such as urban land, pits or water).

Statewide, 65% of the land is very limited, so Bernalillo County is more 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 7% of the land (2% 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 (67%). 90% of the land is moderately well drained or better, compared with 84% across New Mexico.

Excessively drained 5%
Somewhat excessively drained 18%
Well drained 67%
Moderately well drained 0%
Somewhat poorly drained <1%
Poorly drained <1%
Very poorly drained 0%
Not rated 9%
Natural drainage class, share of mapped land in Bernalillo County. Scale 0 to 100% of mapped land.
Show as a table
Natural drainage class, share of mapped land in Bernalillo County.
CategoryBernalillo CountyNew Mexico
Excessively drained5.1%2.9%
Somewhat excessively drained17.9%3.4%
Well drained67.3%76.7%
Moderately well drained0.0%0.9%
Somewhat poorly drained0.5%0.4%
Poorly drained0.4%0.2%
Very poorly drained0.0%0.1%
Not rated8.8%15.5%

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 14%
Somewhat limited 13%
Very limited 71%
Not rated 2%
Septic tank absorption field rating, share of mapped land in Bernalillo County. Scale 0 to 100% of mapped land.
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Septic tank absorption field rating, share of mapped land in Bernalillo County.
CategoryBernalillo CountyNew Mexico
Not limited13.6%5.6%
Somewhat limited13.3%17.8%
Very limited71.1%65.3%
Not rated2.0%11.3%

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) 33%
B: moderate infiltration 21%
C: slow infiltration 27%
D: very slow infiltration (clayey, shallow or wet) 18%
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%
Not rated 1%
Hydrologic soil group, share of mapped land in Bernalillo County. Scale 0 to 100% of mapped land.
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Hydrologic soil group, share of mapped land in Bernalillo County.
CategoryBernalillo CountyNew Mexico
A: fast infiltration (mostly sandy or gravelly)33.4%10.8%
B: moderate infiltration20.6%22.9%
C: slow infiltration27.0%23.1%
D: very slow infiltration (clayey, shallow or wet)17.8%31.0%
A/D: D as is, A if drained0.0%0.1%
B/D: D as is, B if drained0.0%0.1%
C/D: D as is, C if drained0.0%0.1%
Not rated1.2%11.9%

Flooding

No flooding 91%
Rare or very rare 6%
Occasional 2%
Frequent or very frequent <1%
Not reported 2%
Most frequent flooding class in any month, share of mapped land in Bernalillo County. Scale 0 to 100% of mapped land.
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Most frequent flooding class in any month, share of mapped land in Bernalillo County.
CategoryBernalillo CountyNew Mexico
No flooding90.9%83.6%
Rare or very rare5.6%3.8%
Occasional1.8%2.2%
Frequent or very frequent0.1%1.2%
Not reported1.5%9.1%

Seasonal high water table

Within 18 inches at some time of year 0%
18 inches to 3.3 feet <1%
Deeper than 3.3 feet or none reported 98%
Not reported 2%
Shallowest depth to a saturated zone in any month, share of mapped land in Bernalillo 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 Bernalillo County.
CategoryBernalillo CountyNew Mexico
Within 18 inches at some time of year0.0%0.6%
18 inches to 3.3 feet0.2%0.3%
Deeper than 3.3 feet or none reported98.3%90.1%
Not reported1.5%9.0%

Topsoil pH and texture

First mineral layer of each soil

Typical topsoil pH is 8.2 (moderately alkaline); 80% of rated land falls between 7.5 and 8.2. Median topsoil organic matter is 0.7%.

Strongly acidic (below 5.5) 0%
Moderately to slightly acidic (5.5–6.4) <1%
Near neutral (6.5–7.3) 7%
Alkaline (7.4 and up) 83%
Not reported 10%
Topsoil pH band, share of mapped land in Bernalillo County. Scale 0 to 100% of mapped land.
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Topsoil pH band, share of mapped land in Bernalillo County.
CategoryBernalillo CountyNew Mexico
Strongly acidic (below 5.5)0.0%0.3%
Moderately to slightly acidic (5.5–6.4)0.1%1.6%
Near neutral (6.5–7.3)6.6%23.7%
Alkaline (7.4 and up)83.1%58.0%
Not reported10.1%16.4%

Texture

Sandy 42%
Loamy (loam, silt loam and similar) 48%
Clayey (40%+ clay) 0%
Organic (muck or peat) 0%
Not reported (rock, urban land, etc.) 10%
Topsoil texture group, share of mapped land in Bernalillo County. Scale 0 to 100% of mapped land.
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Topsoil texture group, share of mapped land in Bernalillo County.
CategoryBernalillo CountyNew Mexico
Sandy42.0%14.8%
Loamy (loam, silt loam and similar)47.8%65.4%
Clayey (40%+ clay)0.0%1.1%
Organic (muck or peat)0.0%0.0%
Not reported (rock, urban land, etc.)10.1%18.7%

Most common surface textures: loamy fine sand 22% · fine sandy loam 17% · very fine sandy loam 8% · bedrock 8% · loam 8%.

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
Bernalillo County, New Mexico (FIPS 35001): 749,293 acres of mapped land, 1,214 acres of open water excluded. State comparisons pool all mapped land in New Mexico.
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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