District of Columbia Water Quality Brief
State: District of Columbia (DC) Grade: D | Score: 68/100 | National Average: 67/100 (Grade: D) Data as of: 2026-04-30 | Brief generated: 2026-04-30
Key Findings
- District of Columbia earned a water quality grade of D with an average score of 68/100 — 1 points above the national average.
- ZipCheckup recorded 9,042 total violations across 286 ZIP codes, including 1,644 health-based violations.
- The worst ZIP code in the state (20373) scored only 50/100, while the best (20003) scored 72/100 — a gap of 22 points.
Worst 5 ZIP Codes
| ZIP | City | County | Score | Grade | Violations |
|---|---|---|---|---|---|
| 56972 | Parcel Return Service | District of Columbia | 50/100 | D | 0 |
| 56944 | Parcel Return Service | District of Columbia | 50/100 | D | 0 |
| 56933 | Parcel Return Service | District of Columbia | 50/100 | D | 0 |
| 56920 | Parcel Return Service | District of Columbia | 50/100 | D | 0 |
| 56915 | Parcel Return Service | District of Columbia | 50/100 | D | 0 |
County Breakdown (Worst 3)
| County | Avg Score | Grade | ZIP Count | Worst ZIP |
|---|---|---|---|---|
| District of Columbia | 68/100 | C | 284 | 56972 (Parcel Return Service, 50/100) |
Violation Summary
| Category | Count |
|---|---|
| Total violations | 9,042 |
| Health-based violations | 1,644 |
| Monitoring/Reporting violations | 7,398 |
| ZIP codes analyzed | 286 |
| Health violations per ZIP (avg) | 5.7 |
Top health-based violation categories:
- Haloacetic Acids (HAA5) (822 violations across 274 ZIP codes)
- Consumer Confidence Report Rule (2,466 violations across 274 ZIP codes)
- E. coli (1,918 violations across 274 ZIP codes)
PFAS Contamination Status
- PFAS detected in 270 of 270 ZIP codes analyzed (100%).
Comparison to National Average
| Metric | DC | National |
|---|---|---|
| Avg Score | 68/100 | 67/100 |
| Grade | D | D |
| Health violations / ZIP | 5.7 | — |
About This Data
Data: ZipCheckup.com | Sources: EPA SDWIS, FEMA, CDC, Census | License: CC BY 4.0
Press contact: [email protected] General contact: [email protected] State page: https://zipcheckup.com/states/district-of-columbia/
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