Community Water System · PWS CO0103005
Aurora City Of
Operator location Aurora, Colorado - larger served population (> 3,309) at 533,407 people served; 18 SDWIS violations on record from surface water sources.
- 533,407
- People served (this PWS)
- 18
- EPA violations (this PWS)
- 4
- Health-based (this PWS)
- 4 PFAS
- UCMR5 (this PWS)
Aurora City Of standing, low SDWIS violation third
533,407 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 22% is middle-third health share (≤ 23%). UCMR5: middle-third PFAS panel (≤ 4 compounds). Population rank #62 of 29,740 among systems serving 500+.
The verdict
Aurora City Of is in the lower third by violation count (18; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is large (533,407; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 22% (middle-third health share (≤ 23%)). UCMR5 detected 4 PFAS compounds (middle-third PFAS panel (≤ 4 compounds)).
- #62 of 29,740
- Population · /systems
- #2 of 551
- Population · CO
- 18
- Total EPA violations on record
- 22%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
4 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 91,821
- County
- Arapahoe
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 13
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| TTHM | MR | 5 | 2016 |
| Total Haloacetic Acids (HAA5) | MR | 5 | 2016 |
| Coliform (TCR) | MCL | 4 | 2011 |
| Interim Enhanced Surface Water Treatment Rule | MR | 3 | 2011 |
Violation Count vs. the National Corpus
Aurora City Of has 18 recorded EPA violations, 29% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 70% carry more. 22% of this system's own violations are health-based (4 of 18), and it ranks #62 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)
18 Lower than most fewer violations than 70% 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. 4 of 348 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFHpS | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 9/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| NMeFOSAA | 9/11/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| NEtFOSAA | 9/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 9/11/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| 8:2 FTS | 9/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 9/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| ADONA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 9/11/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| NFDHA | 9/11/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFHxA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 9/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 9/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 9/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBA | 9/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDoA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 9/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 9/11/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 9/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 9/11/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 4:2 FTS | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 9/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDA | 9/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 8/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFNA | 8/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 8/5/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| NEtFOSAA | 8/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 8/5/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFPeA | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 8/5/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFMBA | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 8/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 8/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFMPA | 8/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 8/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 8/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxA | 8/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 8/5/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
Population served record for Aurora City Of
EPA SDWIS lists 533,407 people served and 91,821 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS · Colorado Department of Public Health and Environment, Water Quality Control
Nationwide peers
18 violations · 533,407 served: nearest cross-state SDWIS matches.
Cross-state systems with similarly light violation ledgers
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
- Cheyenne Arapaho Concho EPA Region 6 — Tribal Water Systems 18violations
- Assiniboine & Sioux Rural Water System EPA Region 8 — Tribal Water Systems 18violations
- Poplar, City Of EPA Region 8 — Tribal Water Systems 18violations
- Torreon-Ojo Encino East - NTUA EPA Region 9 — Tribal Water Systems 18violations
Cross-state systems with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Aurora City Of
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Colorado compares on the same EPA violation measures. Colorado 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.