San Saba County, TX's soil, for a septic absorption field

Very limited

98.2% of San Saba County, TX's surveyed soil comes back "Very limited" in USDA's own SSURGO data, the county's dominant condition for a septic absorption field. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 98.2% of San Saba County's land. San Saba County covers 1,135.313 square miles and counts 5,508 residents.

This is a county figure, not a parcel figure

Two lots a mile apart in San Saba County can carry different soil, even though they share one countywide rating. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in San Saba County.

System cost, conventional vs. engineered

Given San Saba County's rating, plan for the engineered-system range rather than the conventional one. The engineered-system range, $10,000-$40,000 (mound or aerobic treatment), is the more realistic number to plan around, against $3,000-$8,000 for a conventional system on the rare lot that passes.

Where this sits nationally

Nationally, San Saba County, TX is the 224-most-constrained of 3,058 rated counties for septic soil. Within Texas alone it ranks 14 of 253.

Further reading

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