Fergus County's SSURGO septic rating

Very limited

Fergus County, MT's SSURGO dominant class comes back "Very limited", covering 88.2% of the county. A standard gravity system routinely fails on ground like this; the same share of the county falls in USDA's worst absorption-field bucket outright. For scale: 4,339.329 square miles and 11,862 people call Fergus County home.

Before you rely on this for one lot

Nothing about Fergus County, MT's SSURGO figure applies to a specific address - it's a county-wide average. The real answer for one lot is still a site-specific perc test, running about $750-$1,850 (typically near $1,300).

Budgeting for a system in Fergus County, MT

Fergus County's soil reading pushes the likely outcome toward an engineered system rather than a conventional one. 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.

Fergus County's rank among Montana counties

Among the 3,058 rated counties on this site, Fergus County, MT ranks 1,452 most-constrained nationally, and 7 of 54 within Montana.

Related guides

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