Annual Report
The American Water Quality Report 2026
11.5M Americans served by D- or F-rated water systems. 23% of systems have health violations.
Published April 2026 · EPA SDWIS data through Q1 2026
Executive Summary
This report evaluates the safety of 190 public water systems serving 73.3M Americans. The findings paint a mixed picture: while most major metropolitan systems maintain acceptable water quality, 23% of all analyzed systems carry at least one health-based violation, and 31 systems earn a D or F safety grade — collectively serving 11.5M people.
Contaminant exceedances affect 17 systems, with 324 total health violations documented across the database. Enforcement actions have been taken against 71% of systems, though enforcement rates vary dramatically by state — suggesting inconsistent regulatory oversight.
PFAS contamination continues to emerge as a defining water quality issue of this decade. 5 systems show PFAS detections above the newly established EPA maximum contaminant levels. The full scope of PFAS contamination is likely underrepresented in current data, as many smaller systems have not yet completed mandated testing.
10 Lowest-Rated Water Systems
| System | State | Population | Health Violations | Score | Grade |
|---|---|---|---|---|---|
| City of Jackson | MS | 189,673 | 100 | 0/100 | F |
| Newark Water Department | NJ | 294,274 | 22 | 5/100 | F |
| Tuscaloosa Water & Sewer | AL | 166,524 | 6 | 8/100 | F |
| Atlanta | GA | 1,089,893 | 5 | 10/100 | F |
| Shreveport Water System | LA | 192,378 | 76 | 10/100 | F |
| Mobile, Bd. Of W&s Comm. Of the City Of | AL | 279,000 | 4 | 16/100 | F |
| Bjw&sa (0720003) | SC | 145,634 | 4 | 16/100 | F |
| Papillion, City Of | NE | 35,000 | 3 | 32/100 | F |
| Gilbert, Town Of | AZ | 247,600 | 3 | 33/100 | F |
| Liberty Utilities New York - Lynbrook | NY | 220,000 | 6 | 34/100 | F |
Most Common Contaminant Exceedances
| Contaminant | Category | Systems Exceeding MCL | Population Affected |
|---|---|---|---|
| Total Trihalomethanes | Disinfection Byproduct | 9 | 2.5M |
| Haloacetic Acids (haa5) | Disinfection Byproduct | 6 | 3.4M |
| PFOS/PFOA (PFAS) | Synthetic Chemical | 5 | 1.6M |
| Lead | Inorganic Chemical | 3 | 528K |
| Nitrate | Inorganic Chemical | 1 | 1.3M |
| Chlorine (Disinfectant) | Disinfectant | 1 | 167K |
| Arsenic | Inorganic Chemical | 1 | 1.6M |
| Total Coliform | Microbial | 0 | 0 |
State-by-State Water Quality
Highest-Rated States
Lowest-Rated States
Enforcement and Compliance
Enforcement action has been taken against 71% of water systems in our database, but enforcement rates vary significantly by state. Some states take aggressive enforcement action against violators, while others rely on compliance assistance and voluntary correction — leading to prolonged periods of non-compliance that leave residents exposed to contaminated water.
The gap between violation detection and enforcement resolution remains a systemic concern. Systems can carry open violations for years without meaningful consequence, particularly smaller rural systems with limited financial resources to fund infrastructure upgrades.
Methodology
This report analyzes EPA Safe Drinking Water Information System (SDWIS) data covering 190 public water systems across 38 states. The Water Safety Score weights health-based violations (40%), contaminant MCL exceedances (30%), enforcement action history (20%), and monitoring/reporting compliance (10%). See our full methodology for details.
Cite This Report
WaterSafety. "The American Water Quality Report 2026." iswatersafe.com, April 2026. https://www.iswatersafe.com/report/water-quality-report-2026
Frequently Asked Questions
Approximately 11.5M Americans are served by water systems that earned a D or F safety grade, meaning they have significant health-based violations, contaminant exceedances, or enforcement actions. 23% of all analyzed systems have at least one health violation on record.
5 water systems in our database show PFAS-related exceedances, affecting approximately 1.6M people. PFAS (per- and polyfluoroalkyl substances) are persistent chemicals linked to cancer, immune system effects, and developmental issues. EPA has recently established enforceable MCLs for several PFAS compounds.
New Jersey, Alabama, Arizona rank lowest in average water system safety scores. These states have higher rates of health violations and contaminant exceedances relative to the number of systems monitored.
The Water Safety Score (0-100, graded A-F) evaluates four factors: health-based violations (40%), contaminant exceedances above MCLs (30%), enforcement action history (20%), and monitoring/reporting violations (10%). Higher scores indicate safer water systems.
The most frequently exceeded contaminants include Total Trihalomethanes, Haloacetic Acids (haa5), PFOS/PFOA (PFAS). Each contaminant page on our site explains health effects, EPA maximum contaminant levels, treatment options, and which water systems are affected.
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