Septic suitability in Benton County, MN
Very limited
USDA puts Benton County, MN at "Very limited" for septic absorption fields, the dominant reading across 98.1% of the county's soil. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 98.1% of the county. The county spans 408.303 square miles, home to 41,881 people.
What this number does and doesn't tell you
Benton 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.
Benton County: conventional vs. engineered cost
98.1% of Benton 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, Benton County, MN ranks 230 most-constrained nationally, and 8 of 86 within Minnesota.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems