Septic soil in Broadwater County, MT, by the numbers

Very limited

59.2% of Broadwater County, MT's surveyed soil comes back "Very limited" in USDA's own SSURGO data, the county's dominant condition for a septic absorption field. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 59.2% of the county. Broadwater County, MT is 1,192.359 square miles with a population of 8,302.

What Broadwater County's reading doesn't cover

Broadwater County's rating is an average across the whole county, not a promise about any one lot inside it. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Broadwater County will actually do.

What a system would cost here

With 59.2% of Broadwater County rating "Very limited", a standard gravity system is not a safe assumption here. The engineered-system range, $10,000-$40,000 (mound or aerobic treatment), is the more realistic number to plan around, against $3,000-$8,000 for a conventional system on the rare lot that passes.

Where this sits nationally

Nationally, Broadwater County, MT is the 2,735-most-constrained of 3,058 rated counties for septic soil. Within Montana alone it ranks 54 of 54.

Before you act on this

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