Cumberland County, ME: the USDA septic-suitability picture
Very limited
USDA puts Cumberland County, ME at "Very limited" for septic absorption fields, the dominant reading across 77.9% of the county's soil. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 77.9% of Cumberland County's land. For scale: 836.231 square miles and 313,809 people call Cumberland County home.
Before you rely on this for one lot
USDA's survey covers the whole of Cumberland County, ME at once, not any single address. 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 Cumberland County, ME
Cumberland 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.
Cumberland County's rank among Maine counties
Among the 3,058 rated counties on this site, Cumberland County, ME ranks 2,140 most-constrained nationally, and 11 of 16 within Maine.
Before you act on this
How this rating is built, and its real limits · Conventional vs. engineered septic systems