Septic soil in Colleton County, SC, by the numbers

Very limited

In Colleton County, SC, 93.1% of the surveyed land carries a "Very limited" rating for a standard septic drain field. 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. Colleton County covers 1,056.509 square miles and counts 39,259 residents.

This is a county figure, not a parcel figure

Colleton County's rating is an average across the whole county, not a promise about any one lot inside it. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Colleton County.

System cost, conventional vs. engineered

Given Colleton 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 Colleton County, SC compares

Nationally, Colleton County, SC is the 910-most-constrained of 3,058 rated counties for septic soil. Within South Carolina alone it ranks 8 of 46.

Before you act on this

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