Septic suitability in Travis County, TX
Very limited
Travis County, TX's SSURGO dominant class comes back "Very limited", covering 91.4% of the county. That reading means a conventional system is a poor bet here - 91.4% of Travis County lands in the strictest "very limited" bucket USDA uses. The county spans 994.329 square miles, home to 1,363,767 people.
What this number does and doesn't tell you
Two lots a mile apart in Travis County can carry different soil, even though they share one countywide rating. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.
Travis County: conventional vs. engineered cost
91.4% of Travis 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.
Where this sits nationally
Among the 3,058 rated counties on this site, Travis County, TX ranks 1,110 most-constrained nationally, and 80 of 253 within Texas.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems