Community Water System · PWS AZ0402035
City of Willcox
Operator location Willcox, Arizona - upper-third violation load (> 74 violations) with 220 EPA violations; groundwater source; 3,236 served (PWS-level, not municipal population).
- 3,236
- People served (this PWS)
- 220
- EPA violations (this PWS)
- 5
- Health-based (this PWS)
- No PFAS
- UCMR5 (this PWS)
City of Willcox standing, high SDWIS violation third
220 EPA SDWIS violations on record - upper-third violation load (> 74 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 2% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #10,076 of 29,740 among systems serving 500+.
The verdict
City of Willcox sits in the upper third of the sitemap cohort by violation count (220), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 3,236 (mid served population (≤ 3,309)). Health-based share is 2% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #10,076 of 29,740
- Population · /systems
- #148 of 413
- Population · AZ
- 220
- Total EPA violations on record
- 2%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 1,806
- County
- Cochise
- School/Daycare
- No
- MCL Violations
- 5
- Monitoring Violations
- 169
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Chlorine | MR | 55 | 2023 |
| Coliform (TCR) | MR | 22 | 2014 |
| Total Haloacetic Acids (HAA5) | MR | 15 | 2023 |
| TTHM | MR | 14 | 2023 |
| Revised Total Coliform Rule | RPT | 11 | 2023 |
| Consumer Confidence Rule | Other | 10 | 2025 |
| Revised Total Coliform Rule | MON | 9 | 2020 |
| Lead and Copper Rule | MR | 7 | 2023 |
| Coliform (TCR) | MCL | 5 | 2012 |
| Nitrate | MR | 5 | 2005 |
| Public Notice | Other | 4 | 2022 |
| Fluoride | MR | 3 | 1998 |
| Arsenic | MR | 3 | 1998 |
| Cadmium | MR | 2 | 1998 |
| Chromium | MR | 2 | 1998 |
| Mercury | MR | 2 | 1998 |
| Selenium | MR | 2 | 1998 |
| Barium | MR | 2 | 1998 |
| CYANIDE | MR | 1 | 1998 |
| Antimony, Total | MR | 1 | 1998 |
| Thallium, Total | MR | 1 | 1998 |
| Xylenes, Total | MR | 1 | 1998 |
| DICHLOROMETHANE | MR | 1 | 1998 |
| o-Dichlorobenzene | MR | 1 | 1998 |
| 1,1-Dichloroethylene | MR | 1 | 1998 |
| 1,1,1-Trichloroethane | MR | 1 | 1998 |
| 1,2-Dichloropropane | MR | 1 | 1998 |
| Trichloroethylene | MR | 1 | 1998 |
| 1,1,2-Trichloroethane | MR | 1 | 1998 |
| Tetrachloroethylene | MR | 1 | 1998 |
Violation Count vs. the National Corpus
City of Willcox has 220 recorded EPA violations, 87% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 13% carry more. 2% of this system's own violations are health-based (5 of 220), and it ranks #10,076 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
220 Higher than most more violations than 87% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 58 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| HFPO-DA | 7/9/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 7/9/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 7/9/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 7/9/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMBA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 7/9/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFMPA | 7/9/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/9/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFUnA | 7/9/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 7/9/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHpA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 7/9/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOS | 7/9/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHpS | 7/9/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 7/9/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTA | 7/9/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 7/9/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 7/9/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 7/9/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| NFDHA | 7/9/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
| 9Cl-PF3ONS | 2/24/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFMBA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 2/24/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 2/24/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 2/24/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 2/24/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOA | 2/24/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| ADONA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 2/24/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 2/24/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 2/24/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 2/24/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeS | 2/24/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 2/24/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
SDWIS compliance record for City of Willcox
220 violations on record for AZ0402035; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.
Sources: EPA SDWIS · Arizona DEQ, Drinking Water Program
Nationwide peers
220 violations · 3,236 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with City of Willcox
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Arizona compares on the same EPA violation measures. Arizona systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.