Jefferson County, MT Septic Rating

Jefferson County, MT: the USDA septic-suitability picture

Very limited

Jefferson County, MT: USDA's soil survey calls 67.7% of the county "Very limited" for a septic leach field. That reading means a conventional system is a poor bet here - it's already USDA's strictest "very limited" bucket, not a partial constraint. The county spans 1,657 square miles, home to 13,304 people.

What this number does and doesn't tell you

Two lots a mile apart in Jefferson 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.

Jefferson County: conventional vs. engineered cost

67.7% of Jefferson 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 Jefferson County, MT compares

Among the 3,058 rated counties on this site, Jefferson County, MT ranks 2,540 most-constrained nationally, and 50 of 54 within Montana.

Further reading

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