Septic companies in Charleston, SC

What the ground in Charleston is like

The USDA soil survey rates mapped ground in Charleston for septic drain-field suitability across roughly 115 square miles. About 95% of the rated ground is classed "Very limited", meaning the soil has one or more features unfavorable for a conventional drain field, and the limits generally cannot be overcome without major soil reclamation, special design or expensive installation.

In Charleston, the leading limit is depth to the saturated zone: the water table sits so close to the surface that a drain field has little dry soil left underneath it. Effluent needs unsaturated ground to treat and disperse; when that column is thin, the field has nowhere safe to go. The survey flags that limit on about 88% of the rated ground here.

The limiting features the survey records most often here:

• Depth to saturated zone87.9%
• Seepage, bottom layer62.7%
• Slow water movement44.8%
• Ponding31.2%

This is survey data for mapped areas, not a substitute for a site evaluation on your own lot. Conditions on a single parcel can differ from the map.

USDA NRCS SSURGO, ENG Septic Tank Absorption Fields · 94.9% Very limited · Depth to saturated zone · 68 map units · 115.32 sq mi · read 2026-08-30