Wyoming Water Quality Brief
State: Wyoming (WY) Grade: F | Score: 55/100 | National Average: 67/100 (Grade: D) Data as of: 2026-04-30 | Brief generated: 2026-04-30
Key Findings
- Wyoming earned a water quality grade of F with an average score of 55/100 — 12 points below the national average.
- ZipCheckup recorded 747 total violations across 195 ZIP codes, including 134 health-based violations.
- The worst ZIP code in the state (82222) scored only 13/100, while the best (82730) scored 83/100 — a gap of 70 points.
Worst 5 ZIP Codes
| ZIP | City | County | Score | Grade | Violations |
|---|---|---|---|---|---|
| 82222 | Lance Creek | Niobrara | 13/100 | F | 18 |
| 82321 | Baggs | Carbon | 30/100 | F | 17 |
| 82329 | Medicine Bow | Carbon | 32/100 | F | 2 |
| 82010 | Cheyenne | Laramie | 32/100 | F | 6 |
| 82008 | Cheyenne | Laramie | 32/100 | F | 6 |
County Breakdown (Worst 3)
| County | Avg Score | Grade | ZIP Count | Worst ZIP |
|---|---|---|---|---|
| Laramie | 43/100 | D | 17 | 82010 (Cheyenne, 32/100) |
| Niobrara | 44/100 | D | 6 | 82222 (Lance Creek, 13/100) |
| Sheridan | 48/100 | D | 13 | 82845 (Wyarno, 40/100) |
Violation Summary
| Category | Count |
|---|---|
| Total violations | 747 |
| Health-based violations | 134 |
| Monitoring/Reporting violations | 613 |
| ZIP codes analyzed | 195 |
| Health violations per ZIP (avg) | 0.7 |
Top health-based violation categories:
- Stage 1 DBP Rule (123 violations across 60 ZIP codes)
- Consumer Confidence Report Rule (149 violations across 55 ZIP codes)
- Contaminant 0700 (46 violations across 34 ZIP codes)
PFAS Contamination Status
- PFAS detected in 6 of 38 ZIP codes analyzed (16%).
- 4 ZIP codes with federal PFAS exceedances.
Comparison to National Average
| Metric | WY | National |
|---|---|---|
| Avg Score | 55/100 | 67/100 |
| Grade | F | D |
| Health violations / ZIP | 0.7 | — |
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/wyoming/
ZipCheckup.com analyzes drinking water quality, flood risk, lead exposure, and other home safety factors for every US ZIP code using data from 50+ federal sources.