Tucson-Avra Valley Area, Arizona
The most common soil here is Anthony, on about 15% of the land: a sandy loam, gritty and crumbly. Grabe and Anway come next.
About all of the land drains well.
USDA rates 38% of the land very limited for a standard septic drain field, and 73% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 4% of the land floods occasionally or more.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Tucson-Avra Valley Area, Arizona, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is A (high infiltration, low runoff). The most common soil order is Aridisols — dry-climate soils with limited organic matter and often calcium carbonate accumulation. 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 Tucson-Avra Valley Area, Arizona. 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 |
|---|---|---|---|---|---|
| Anthony gravelly sandy loam,1 to 3 percent slopes | 14K | Well drained | A | Very limited | Somewhat limited |
| Grabe loam | 14K | Well drained | B | Very limited | Somewhat limited |
| Gila loam, 0 to 1 percent slopes | 10K | Well drained | B | Very limited | Somewhat limited |
| Anway loam | 9K | Well drained | B | Very limited | Somewhat limited |
| Anway silty clay loam | 8K | Well drained | B | Very limited | Somewhat limited |
| Grabe silty clay loam | 7K | Well drained | C | Very limited | Somewhat limited |
| Comoro sandy loam | 6K | Well drained | A | Very limited | Somewhat limited |
| Valencia sandy loam, 0 to 1 percent slopes | 6K | Well drained | C | Very limited | Very limited |
| Anthony sandy loam, 0 to 1 percent slopes | 5K | Well drained | A | Very limited | Somewhat limited |
| Pima silty clay loam | 5K | Well drained | C | Very limited | Very limited |
| Rough broken land-Palos Verdes complex, 0 to 60 percent slopes | 5K | Well drained | Very limited | Very limited | |
| Valencia-Sonoita sandy loams, 1 to 5 percent slopes | 5K | Well drained | C | Very limited | Very limited |
| Gravelly alluvial land | 5K | Excessively drained | Very limited | Very limited | |
| Sonoita sandy loam, 0 to 1 percent slopes | 4K | Well drained | A | Somewhat limited | Not limited |
| Anthony and Sonoita soils, 0 to 5 percent slopes | 4K | Well drained | A | Very limited | Somewhat limited |
| Vinton-anthony sandy loams | 4K | Well drained | A | Very limited | Very limited |
| Anthony sandy loam, 1 to 3 percent slopes | 4K | Well drained | A | Very limited | Somewhat limited |
| Mohave clay loam | 4K | Well drained | C | Somewhat limited | Very limited |
| Vekol silty clay loam | 3K | Well drained | C | Very limited | Very limited |
| Sonoita sandy clay loam | 3K | Well drained | A | Somewhat limited | Not 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.
What This Means
Building & Foundations
About 73% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 38% of soils have significant septic limitations, while others are more suitable. A perc test is essential — conditions vary across the area.
Gardening & Agriculture
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.