Community Water System · PWS PA4410173
Williamsport Mun Water Auth
Operator location Williamsport, Pennsylvania - UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)) on this PWS; SDWIS lists 73 violations and 51,000 people served.
- 51,000
- People served (this PWS)
- 73
- EPA violations (this PWS)
- 1
- Health-based (this PWS)
- 5 PFAS
- UCMR5 (this PWS)
Williamsport Mun Water Auth standing, mid SDWIS violation third
UCMR5 detected 5 PFAS compounds - upper-third PFAS panel (> 4 compounds). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 1% is middle-third health share (≤ 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #1,060 of 29,740 among systems serving 500+.
The verdict
Williamsport Mun Water Auth lands in the middle third by violation volume (73), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is large (51,000; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 1% (middle-third health share (≤ 23%)). UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)).
- #1,060 of 29,740
- Population · /systems
- #34 of 1,340
- Population · PA
- 73
- Total EPA violations on record
- 1%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
5 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 18,558
- County
- Lycoming
- School/Daycare
- No
- MCL Violations
- 1
- Monitoring Violations
- 41
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Total Haloacetic Acids (HAA5) | MR | 7 | 2018 |
| TTHM | MR | 7 | 2018 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2012 |
| Xylenes, Total | MR | 1 | 2012 |
| DICHLOROMETHANE | MR | 1 | 2012 |
| o-Dichlorobenzene | MR | 1 | 2012 |
| 1,1-Dichloroethylene | MR | 1 | 2012 |
| 1,2-Dichloroethane | MR | 1 | 2012 |
| Carbon tetrachloride | MR | 1 | 2012 |
| 1,2-Dichloropropane | MR | 1 | 2012 |
| Trichloroethylene | MR | 1 | 2012 |
| 1,1,2-Trichloroethane | MR | 1 | 2012 |
| Benzene | MR | 1 | 2012 |
| Toluene | MR | 1 | 2012 |
| Mercury | MR | 1 | 1984 |
| Barium | MR | 1 | 1984 |
| Selenium | MR | 1 | 1984 |
| Arsenic | MR | 1 | 1984 |
| Endrin | MR | 1 | 1982 |
| Cadmium | MR | 1 | 1984 |
| Ethylbenzene | MR | 1 | 2012 |
| Tetrachloroethylene | MR | 1 | 2012 |
| CHLOROBENZENE | MR | 1 | 2012 |
| 1,1,1-Trichloroethane | MR | 1 | 2012 |
| cis-1,2-Dichloroethylene | MR | 1 | 2012 |
| p-Dichlorobenzene | MR | 1 | 2012 |
| Chromium | MR | 1 | 1983 |
| trans-1,2-Dichloroethylene | MR | 1 | 2012 |
| Styrene | MR | 1 | 2012 |
| TTHM | MCL | 1 | 1985 |
Violation Count vs. the National Corpus
Williamsport Mun Water Auth has 73 recorded EPA violations, 66% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 34% carry more. 1% of this system's own violations are health-based (1 of 73), and it ranks #1,060 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)
73 Around the middle fewer violations than 34% 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. 8 of 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFBA | 9/3/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 9/3/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| NEtFOSAA | 9/3/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 9/3/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFTA | 9/3/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFHpS | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 9/3/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 9/3/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 9/3/2024 | 4.10 ppt | 3.00 ppt | Detected |
| PFMPA | 9/3/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 9/3/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpA | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 9/3/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| HFPO-DA | 9/3/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 9/3/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 9/3/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 9/3/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 9/3/2024 | 3.50 ppt | 3.00 ppt | Detected |
| PFDoA | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 9/3/2024 | 5.10 ppt | 4.00 ppt | Detected |
| PFNA | 9/3/2024 | 9.70 ppt | 4.00 ppt | Detected |
| PFHxS | 9/3/2024 | 3.60 ppt | 3.00 ppt | Detected |
| PFBS | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 9/3/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 9/3/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| NMeFOSAA | 6/5/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| HFPO-DA | 6/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBS | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 6/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 6/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 6/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDA | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 6/5/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| NEtFOSAA | 6/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 6/5/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFBA | 6/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 6/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 6/5/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 6/5/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 6/5/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
UCMR5 PFAS record for Williamsport Mun Water Auth
Open EPA SDWIS federal reports for PWS PA4410173 to cross-check UCMR5 detections and violation codes; state primacy agencies enforce the Safe Drinking Water Act locally.
Sources: EPA SDWIS · Pennsylvania DEP, Bureau of Safe Drinking Water
Nationwide peers
73 violations · 51,000 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Williamsport Mun Water Auth
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Pennsylvania compares on the same EPA violation measures. Pennsylvania 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.