Dukes County, MA's soil, for a septic absorption field

Very limited

In Dukes County, MA, 79.1% of the surveyed land carries a "Very limited" rating for a standard septic drain field. That reading means a conventional system is a poor bet here - 79.1% of Dukes County lands in the strictest "very limited" bucket USDA uses. Dukes County covers 103.202 square miles and counts 21,061 residents.

This is a county figure, not a parcel figure

Two lots a mile apart in Dukes County can carry different soil, even though they share one countywide rating. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Dukes County.

System cost, conventional vs. engineered

Given Dukes County's rating, plan for the engineered-system range rather than the conventional one. 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.

How Dukes County, MA compares

Nationally, Dukes County, MA is the 2,089-most-constrained of 3,058 rated counties for septic soil. Within Massachusetts alone it ranks 8 of 14.

Before you act on this

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