South Carolina Water Quality Report: 736 Violations Across 534 ZIPs
595 water systems · 534 ZIP codes · 736 violations · Updated 2026-05-31
Data: EPA Safe Drinking Water Information System (SDWIS), EPA ECHO Last verified: 2026-05-31
City Water Quality Map: South Carolina
Each circle represents a city. Size indicates population, color indicates water quality grade. Tap a circle for details.
Violation Trend
EPA violations across all water systems in South Carolina.
Cities with Most Violations in South Carolina
| # | City | Grade | Violations | Systems | Population | |
|---|---|---|---|---|---|---|
| 1 | Columbia | A | 170 | 5 | 323,067 | Details → |
| 2 | Aiken | C | 60 | 5 | 50,675 | Details → |
| 3 | Anderson | B | 24 | 5 | 73,514 | Details → |
| 4 | Summerville | B | 20 | 5 | 151,109 | Details → |
| 5 | Mount Pleasant | B | 18 | 3 | 91,708 | Details → |
| 6 | Conway | B | 12 | 5 | 313,522 | Details → |
| 7 | Fort Mill | B | 12 | 5 | 28,541 | Details → |
| 8 | Clearwater | A | 12 | 3 | 631 | Details → |
| 9 | Rock Hill | B | 10 | 5 | 84,504 | Details → |
| 10 | York | B | 10 | 5 | 58,632 | Details → |
Cities with Best Water Quality in South Carolina
| # | City | Grade | Score | Systems | Population |
|---|---|---|---|---|---|
| 1 | Chesterfield | A | 99/100 | 2 | 27,361 |
| 2 | Cassatt | A | 99/100 | 1 | 25,485 |
| 3 | Gloverville | A | 99/100 | 2 | 12,113 |
| 4 | Bethune | A | 99/100 | 2 | 3,641 |
| 5 | Pelion | A | 99/100 | 2 | 1,336 |
| 6 | Bowman | A | 99/100 | 1 | 1,274 |
| 7 | Wedgefield | A | 99/100 | 1 | 1,200 |
| 8 | Monetta | A | 99/100 | 1 | 1,152 |
| 9 | Lancaster | A | 96/100 | 2 | 93,181 |
| 10 | Lugoff | A | 95/100 | 1 | 22,873 |
Most Common Contaminants in South Carolina
| Contaminant | Category | Violations | ZIPs Affected | Health Risk |
|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | 207 | 109 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 85 | 34 | Yes |
| Stage 1 DBP Rule | Treatment Technique | 82 | 74 | Yes |
| Stage 2 DBP Rule | Treatment Technique | 56 | 25 | Yes |
| Chlorine residual | Disinfectant | 44 | 7 | Yes |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 40 | 32 | Yes |
| Contaminant 1009 | Other | 34 | 34 | Yes |
| Total Coliform | Microbiological | 25 | 17 | No |
| Revised Total Coliform Rule | Microbiological | 24 | 21 | No |
| E. coli | Microbiological | 14 | 13 | No |
Water Quality Overview
South Carolina has 595 community water systems serving approximately 10,977,830 people across 534 ZIP codes. These systems have accumulated 736 EPA violations, including 246 health-based violations.
Health-based violations account for 33% of all violations in South Carolina. These violations indicate contaminant levels that may pose direct risks to human health, as opposed to monitoring or reporting failures.
Violation Breakdown
| Violation Type | Count | Percentage |
|---|---|---|
| Health-based | 246 | 33.4% |
| Monitoring/Reporting | 490 | 66.6% |
| Total | 736 | 100% |
Health-based violations indicate contaminant levels exceeding EPA Maximum Contaminant Levels (MCLs). Monitoring violations indicate failures to test or report — these do not necessarily mean unsafe water, but they mean the water was not properly verified.
Cities with Most Violations
The following cities in South Carolina have the highest number of EPA violations:
| Rank | City | Grade | Violations | Water Systems | Population |
|---|---|---|---|---|---|
| 1 | Columbia | A | 170 | 5 | 323,067 |
| 2 | Aiken | C | 60 | 5 | 50,675 |
| 3 | Anderson | B | 24 | 5 | 73,514 |
| 4 | Summerville | B | 20 | 5 | 151,109 |
| 5 | Mount Pleasant | B | 18 | 3 | 91,708 |
| 6 | Conway | B | 12 | 5 | 313,522 |
| 7 | Fort Mill | B | 12 | 5 | 28,541 |
| 8 | Clearwater | A | 12 | 3 | 631 |
| 9 | Rock Hill | B | 10 | 5 | 84,504 |
| 10 | York | B | 10 | 5 | 58,632 |
Violation counts are cumulative across all water systems serving each city. Higher counts may reflect larger systems with more monitoring requirements, not necessarily worse water quality.
Cities with Best Water Quality
These South Carolina cities maintain Grade A water with zero violations:
| Rank | City | Grade | Score | Water Systems | Population |
|---|---|---|---|---|---|
| 1 | Chesterfield | A | 99/100 | 2 | 27,361 |
| 2 | Cassatt | A | 99/100 | 1 | 25,485 |
| 3 | Gloverville | A | 99/100 | 2 | 12,113 |
| 4 | Bethune | A | 99/100 | 2 | 3,641 |
| 5 | Pelion | A | 99/100 | 2 | 1,336 |
| 6 | Bowman | A | 99/100 | 1 | 1,274 |
| 7 | Wedgefield | A | 99/100 | 1 | 1,200 |
| 8 | Monetta | A | 99/100 | 1 | 1,152 |
| 9 | Lancaster | A | 96/100 | 2 | 93,181 |
| 10 | Lugoff | A | 95/100 | 1 | 22,873 |
Violation Trend Over Time
Year-by-year EPA violations recorded across all water systems in South Carolina:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2021 | 154 | 154 |
| 2022 | 33 | 33 |
| 2023 | 71 | 71 |
| 2024 | 134 | 134 |
| 2025 | 15 | 15 |
Violations have decreased from 154 in 2021 to 15 in 2025, suggesting improving compliance across South Carolina.
Most Common Contaminants
The following contaminants have caused the most violations across South Carolina water systems:
| Contaminant | Category | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | 207 | 109 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 85 | 34 | Yes |
| Stage 1 DBP Rule | Treatment Technique | 82 | 74 | Yes |
| Stage 2 DBP Rule | Treatment Technique | 56 | 25 | Yes |
| Chlorine residual | Disinfectant | 44 | 7 | Yes |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 40 | 32 | Yes |
| Total Coliform | Microbiological | 25 | 17 | No |
| Revised Total Coliform Rule | Microbiological | 24 | 21 | No |
| E. coli | Microbiological | 14 | 13 | No |
| Fecal Coliform | Microbiological | 2 | 2 | Yes |
How to Check Your Water in South Carolina
Enter your ZIP code on ZipCheckup for detailed water system data including contaminant levels, violation history, and safety scores
Request your CCR — every water utility must provide an annual Consumer Confidence Report
Get a home test — certified kits ($20-$50) or professional lab tests ($150-$400)
Consider filtration — NSF-certified filters can address specific contaminants found in your area
EPA Enforcement
The EPA and state regulators have taken 2,769 enforcement actions against water systems in South Carolina. Enforcement actions range from compliance assistance to formal orders and penalties.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Enforcement: EPA ECHO
Updated daily.
What are EPA violations?
Health-based violations mean a contaminant was detected above the EPA's Maximum Contaminant Level (MCL) — the legal limit designed to protect human health. South Carolina has 246 such violations across its water systems. Not all violations cause illness, but repeated exceedances increase risk, especially for children and immunocompromised individuals.
Understanding water quality grades
ZipCheckup grades water systems from A to F based on EPA violation history, contaminant levels, and system compliance. Grade A means few or no violations; Grade F indicates persistent or serious issues. Grades are calculated per ZIP code and aggregated at the city, county, and state level.
Wondering about your tap water?
Water quality varies by ZIP code. Enter yours to see contaminant data, violations, and filtration recommendations specific to your area.
Check Your ZIP Code Water Quality →Frequently Asked Questions
Is the tap water safe to drink in South Carolina?
South Carolina has 595 community water systems with 736 recorded EPA violations, including 246 health-based. Water quality varies by city and ZIP code — check your specific location for detailed results.
How many water violations does South Carolina have?
South Carolina has 736 total EPA violations across 534 ZIP codes. 246 are health-based violations that indicate contaminant levels potentially harmful to human health. The remainder are monitoring or reporting violations.
Which city in South Carolina has the worst water quality?
Columbia, SC has the most EPA violations among major cities in South Carolina with 170 recorded violations. Check individual ZIP codes for the most accurate picture of your local water quality.
Which city in South Carolina has the best water quality?
Chesterfield, SC ranks among the best for water quality in South Carolina with a grade of A. Multiple cities in South Carolina maintain strong EPA compliance records.
What contaminants are found in South Carolina drinking water?
South Carolina water systems are monitored for over 90 EPA-regulated contaminants including lead, copper, nitrates, disinfection byproducts, and bacteria. The most common violations vary by region — check your ZIP code for contaminant-specific data.