Trigg County, KY: the USDA septic-suitability picture
Very limited
Trigg County, KY: USDA's soil survey calls 64% of the county "Very limited" for a septic leach field. That reading means a conventional system is a poor bet here - 64% of Trigg County lands in the strictest "very limited" bucket USDA uses. The county spans 441.433 square miles, home to 14,559 people.
What this number does and doesn't tell you
Two lots a mile apart in Trigg 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.
Trigg County: conventional vs. engineered cost
64% of Trigg 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.
How Trigg County, KY compares
Among the 3,058 rated counties on this site, Trigg County, KY ranks 2,636 most-constrained nationally, and 106 of 119 within Kentucky.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems