Fort Bend County's SSURGO septic rating
Very limited
Fort Bend County, TX: USDA's soil survey calls 94.4% of the county "Very limited" for a septic leach field. That reading means a conventional system is a poor bet here - 94.4% of Fort Bend County lands in the strictest "very limited" bucket USDA uses. The county spans 862.089 square miles, home to 958,434 people.
What this number does and doesn't tell you
Fort Bend County's rating is an average across the whole county, not a promise about any one lot inside it. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.
Fort Bend County: conventional vs. engineered cost
94.4% of Fort Bend 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, Fort Bend County, TX ranks 717 most-constrained nationally, and 49 of 253 within Texas.
Further reading
How this rating is built, and its real limits · Conventional vs. engineered septic systems