Septic Systems in South Carolina

46 counties · ~40% of homes on septic · ~582,642 septic systems

State Regulation Overview

Regulatory Body
South Carolina DHEC
Inspection Required for Sale
No / Varies by county
Nitrogen Reduction Areas
No
Advanced Treatment Areas
Yes

DHEC issues permits statewide. Soil evaluation required for new installations.

Top Counties by Septic Systems

Lexington County
~35,279 septic homes
York County
~33,851 septic homes
Richland County
~33,292 septic homes
Charleston County
~32,659 septic homes
Horry County
~28,082 septic homes

All Counties in South Carolina

Abbeville County
24K pop · ~48% septic
Aiken County
169K pop · ~30% septic
Allendale County
8K pop · ~56% septic
Anderson County
204K pop · ~30% septic
Bamberg County
13K pop · ~56% septic
Barnwell County
21K pop · ~48% septic
Beaufort County
187K pop · ~30% septic
Berkeley County
230K pop · ~30% septic
Calhoun County
14K pop · ~56% septic
Charleston County
408K pop · ~20% septic
Cherokee County
56K pop · ~40% septic
Chester County
32K pop · ~48% septic
Chesterfield County
43K pop · ~48% septic
Clarendon County
31K pop · ~48% septic
Colleton County
39K pop · ~48% septic
Darlington County
63K pop · ~40% septic
Dillon County
28K pop · ~48% septic
Dorchester County
162K pop · ~30% septic
Edgefield County
26K pop · ~48% septic
Fairfield County
21K pop · ~48% septic
Florence County
137K pop · ~30% septic
Georgetown County
63K pop · ~40% septic
Greenville County
526K pop · ~12% septic
Greenwood County
69K pop · ~40% septic
Hampton County
19K pop · ~48% septic
Horry County
351K pop · ~20% septic
Jasper County
29K pop · ~48% septic
Kershaw County
65K pop · ~40% septic
Lancaster County
96K pop · ~40% septic
Laurens County
68K pop · ~40% septic
Lee County
17K pop · ~48% septic
Lexington County
294K pop · ~30% septic
Marion County
29K pop · ~48% septic
Marlboro County
27K pop · ~48% septic
McCormick County
10K pop · ~56% septic
Newberry County
38K pop · ~48% septic
Oconee County
79K pop · ~40% septic
Orangeburg County
84K pop · ~40% septic
Pickens County
131K pop · ~30% septic
Richland County
416K pop · ~20% septic
Saluda County
19K pop · ~48% septic
Spartanburg County
328K pop · ~20% septic
Sumter County
106K pop · ~30% septic
Union County
27K pop · ~48% septic
Williamsburg County
31K pop · ~48% septic
York County
282K pop · ~30% septic

Septic Systems in South Carolina

Approximately 40% of homes in South Carolina rely on septic systems for wastewater treatment, totaling an estimated 582,642 septic systems across the state's 46 counties. This places South Carolina among the states with significant decentralized wastewater infrastructure.

Septic Regulations in South Carolina

Septic regulations in South Carolina are administered by South Carolina DHEC, with permits typically issued at the county level through local health departments. Requirements for tank sizes, setback distances, approved system types, and inspections can vary significantly between counties.

While South Carolina does not have a statewide mandate for septic inspections at the time of property sale, individual counties may impose their own requirements. It is common practice for buyers to request a septic inspection as part of their due diligence, even when not legally required.

Common Septic System Types

Homeowners in South Carolina typically use one of several septic system types depending on local soil conditions: conventional gravity-fed systems where soil percolation is adequate, pressure distribution systems in areas with moderate limitations, mound systems where shallow bedrock or high water tables prevent conventional installation, and aerobic treatment units (ATUs) in environmentally sensitive areas.

Septic Maintenance Requirements

The EPA recommends pumping septic tanks every 3 to 5 years, though the exact frequency depends on tank size, household size, and water usage. In South Carolina, some counties have adopted mandatory pumping schedules or maintenance tracking programs. Proper maintenance prevents costly repairs, protects groundwater quality, and extends the lifespan of the drainfield — the most expensive component to replace.

Select a county above to view detailed septic regulations, estimated costs, soil suitability data sourced from the USDA NRCS Soil Survey, and groundwater depth measurements from the USGS.

Data last updated: 2026-04-13