Water in South Carolina.
Cape Fear basin PFAS contamination from upstream North Carolina affects multiple South Carolina systems. Coastal groundwater faces saltwater intrusion. Charleston and Columbia draw from river-fed surface systems with consistent TTHM exposure.
How South Carolina regulates drinking water.
Federal SDWA primacy. No state MCLs stricter than federal. PFAS testing expanding under 2024 federal rule.
South Carolina Department of Health and Environmental Control — Bureau of Water
South Carolina's water history, in order.
The contamination events, regulatory shifts, and major settlements that define how this state thinks about drinking water today.
- 2018
PFAS contamination from upstream Chemours documented in Lake Wateree and Catawba basin.
- 2024
Federal PFAS rule triggers expanded testing across SC systems.
The actual water you drink.
The physical rivers, aquifers, lakes, and reservoirs that feed South Carolina's public water systems. Source quality is the foundation of tap quality — and where the long-term protection fights happen.
- riverCatawba-Wateree River
Columbia / Rock Hill / Lake Wateree.
- reservoirLake Murray
Columbia / Lexington.
- riverEdisto + Saluda Rivers
- aquiferCoastal Plain Aquifer
Charleston / Lowcountry.
Source-water mix
~70% surface water, ~30% groundwater
Major cities served
Charleston · Columbia · Greenville · Mount Pleasant · Rock Hill
Who actually serves the water.
The largest public water systems in South Carolina by population served. Click your ZIP after to see the full live EWG report for your specific utility.
- Charleston Water SystemCharleston metro480Kserved
- Columbia WaterColumbia375Kserved
- Greenville WaterGreenville500Kserved
Where the contamination comes from.
Every state has a different industrial fingerprint. The industries below are the dominant historical and active contamination sources in South Carolina's drinking water systems.
Cape Fear basin PFAS / GenX contamination from upstream NC Chemours affects Lake Wateree and downstream Columbia. SCANA and Duke coal-ash impoundments raise heavy-metal concerns. Limited heavy industry compared to NC.
What state data flags most consistently.
Drawn from EPA SDWIS sampling records, EWG state summaries, and regional regulatory action over the past five years. Read the full deep dive on each.
PFAS (Forever Chemicals)
A class of ~15,000 synthetic chemicals that don't break down. Now regulated for the first time.
Trihalomethanes (TTHMs)
Byproducts of chlorinating water. Linked to bladder cancer at chronic exposure.
Lead
A neurotoxic metal that leaches from old pipes and solder. No safe level for children.
Chromium-6 (Hexavalent Chromium)
The Erin Brockovich chemical. A known carcinogen with no federal-specific limit yet.
Risk isn't evenly distributed.
Catawba River downstream communities face Chemours PFAS exposure. Coastal communities face saltwater intrusion.
~17% on private wells, concentrated in rural Lowcountry and Midlands.
What's coming for South Carolina's water.
Hurricane intensity (Florence, Matthew) overwhelms coastal SC treatment. Sea-level rise threatens Charleston / Beaufort wellfields. Catawba-Wateree drought-flood swings stress water-supply storage.
Voluntary statewide
SC DHEC provides voluntary technical assistance.
Five questions for your next Consumer Confidence Report.
Your utility is required to send you a Consumer Confidence Report annually. Most are dense and procedural. These are the questions worth following up on for South Carolina specifically.
- 1
Has my Catawba-Wateree-served utility tested for GenX / PFOA / PFOS?
- 2
Has my coastal well been impacted by saltwater intrusion?
- 3
Has my system been impacted by any SCANA coal-ash basin?
Most state regulators allow public records requests for the underlying lab reports behind your CCR — your utility should be able to provide them on request.
For PFAS in Catawba region: NSF/ANSI P473 or RO. For TTHMs in Lowcountry: NSF/ANSI 53 carbon block.
We don't recommend brands — the NSF/ANSI certification number matters more than the name on the box.
This is the state. Your address is the answer.
State-level patterns don't tell you about your specific tap. Run your ZIP for the live EWG contaminant report on your utility — or build a personalized Water File for your household.
Source-water mix, utility counts, lead-service-line estimates, and private-well shares are approximate, drawn from EPA SDWIS public data and state primacy-agency summaries. Contaminant rankings reflect EWG state-level monitoring data and regional regulatory action — they are not exhaustive. Timeline events are publicly documented. See methodology for the full sourcing. Search EPA SDWIS for South Carolina