Maricopa County's SSURGO septic rating

Very limited

Maricopa County, AZ: USDA's soil survey calls 64.5% of the county "Very limited" for a septic leach field. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 64.5% of Maricopa County's land. The county spans 9,202.021 square miles, home to 4,673,096 people.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Maricopa County, AZ - never a reading for one specific parcel. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.

Maricopa County: conventional vs. engineered cost

64.5% of Maricopa County carrying a "Very limited" reading changes the realistic budget here. Conventional systems run $3,000-$8,000 where they pass; where they don't, engineered alternatives (mound or aerobic treatment, whichever the health department requires) run $10,000-$40,000 - budget toward the higher figure until a perc test says otherwise.

Maricopa County's rank among Arizona counties

Among the 3,058 rated counties on this site, Maricopa County, AZ ranks 2,623 most-constrained nationally, and 12 of 15 within Arizona.

Related guides

How this rating is built, and its real limits · Conventional vs. engineered septic systems