Community Water System · PWS NH2151010
Somersworth Water Works
Operator location Somersworth, New Hampshire - 96% of 160 violations are health-based (upper-third health share (> 23%)); surface water source; 12,000 served per SDWIS.
- 12,000
- People served (this PWS)
- 160
- EPA violations (this PWS)
- 153
- Health-based (this PWS)
- No PFAS
- UCMR5 (this PWS)
Somersworth Water Works standing, high SDWIS violation third
96% of 160 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 96% is upper-third health share (> 23%). UCMR5: UCMR5 tested, none detected. Population rank #4,112 of 29,740 among systems serving 500+.
The verdict
Somersworth Water Works sits in the upper third of the sitemap cohort by violation count (160), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (12,000; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 96% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #4,112 of 29,740
- Population · /systems
- #17 of 284
- Population · NH
- 160
- Total EPA violations on record
- 96%
- 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
- 3,300
- County
- Strafford
- School/Daycare
- No
- MCL Violations
- 143
- Monitoring Violations
- 0
- Treatment Tech Violations
- 10
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Total Haloacetic Acids (HAA5) | MCL | 71 | 2007 |
| TTHM | MCL | 57 | 2007 |
| Coliform (TCR) | MCL | 15 | 1992 |
| CARBON, TOTAL | TT | 10 | 2003 |
| Consumer Confidence Rule | Other | 4 | 2007 |
Violation Count vs. the National Corpus
Somersworth Water Works has 160 recorded EPA violations, 82% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 18% carry more. 96% of this system's own violations are health-based (153 of 160), and it ranks #4,112 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)
160 Higher than most more violations than 82% 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 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| NMeFOSAA | 9/21/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFTrDA | 9/21/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 9/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 9/21/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFBA | 6/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFNA | 6/21/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 6/21/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 6/21/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 6/21/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 6/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 6/21/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| 6:2 FTS | 6/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDoA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 6/21/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 6/21/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 6/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOS | 6/21/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| 4:2 FTS | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 6/21/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 6/21/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| ADONA | 6/21/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 6/21/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOA | 6/21/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTrDA | 3/8/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| NFDHA | 3/8/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| 4:2 FTS | 3/8/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 3/8/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 3/8/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBA | 3/8/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| HFPO-DA | 3/8/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 3/8/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| NEtFOSAA | 3/8/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeA | 3/8/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 3/8/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| NMeFOSAA | 3/8/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 3/8/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDA | 3/8/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 3/8/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBS | 3/8/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 3/8/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
Health-based violations on Somersworth Water Works
153 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for NH2151010.
Sources: EPA SDWIS
Nationwide peers
160 violations · 12,000 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 with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Somersworth Water Works
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in New Hampshire compares on the same EPA violation measures. New Hampshire 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.