PlainWater

Community Water System · PWS MA2187000

Millis Water Dept

Operator location Millis, Massachusetts - UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)) on this PWS; SDWIS lists 98 violations and 9,002 people served.

9,002
People served (this PWS)
98
EPA violations (this PWS)
6
Health-based (this PWS)
5 PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Millis Water Dept standing, high 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 6% is middle-third health share (≤ 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #5,117 of 29,740 among systems serving 500+.

The verdict

Millis Water Dept sits in the upper third of the sitemap cohort by violation count (98), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (9,002; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 6% (middle-third health share (≤ 23%)). UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)).

#5,117 of 29,740
Population · /systems
#182 of 418
Population · MA
98
Total EPA violations on record
6%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

PFAS Detected

5 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

System Details

System Type
Community
Owner Type
Local
Connections
3,068
County
Norfolk
School/Daycare
No
MCL Violations
6
Monitoring Violations
88
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 6 2012
Chlorine MR 4 2011
Nitrate MR 3 2017
Coliform (TCR) MR 3 1994
1,2,4-Trichlorobenzene MR 2 2001
cis-1,2-Dichloroethylene MR 2 2001
Xylenes, Total MR 2 2001
DICHLOROMETHANE MR 2 2001
o-Dichlorobenzene MR 2 2001
trans-1,2-Dichloroethylene MR 2 2001
1,2-Dichloroethane MR 2 2001
1,1,1-Trichloroethane MR 2 2001
1,2-Dichloropropane MR 2 2001
1,1,2-Trichloroethane MR 2 2001
Tetrachloroethylene MR 2 2001
CHLOROBENZENE MR 2 2001
Benzene MR 2 2001
Toluene MR 2 2001
Ethylbenzene MR 2 2001
Styrene MR 2 2001
1,1-Dichloroethylene MR 2 2001
p-Dichlorobenzene MR 2 2001
Groundwater Rule MR 2 2016
Carbon tetrachloride MR 2 2001
Trichloroethylene MR 2 2001
Vinyl chloride MR 2 2001
Dalapon MR 1 1998
Endothall MR 1 1998
Glyphosate MR 1 1998
Di(2-ethylhexyl) adipate MR 1 1998

Violation Count vs. the National Corpus

Millis Water Dept has 98 recorded EPA violations, 73% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 27% carry more. 6% of this system's own violations are health-based (6 of 98), and it ranks #5,117 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)

98 Around the middle fewer violations than 27% 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 232 samples detected PFAS.

Contaminant Date Result MRL Status
PFNA 9/5/2023 <4.00 ppt 4.00 ppt Not Detected
PFBA 9/5/2023 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 9/5/2023 <5.00 ppt 5.00 ppt Not Detected
ADONA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 9/5/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/5/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFDA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 9/5/2023 <5.00 ppt 5.00 ppt Not Detected
PFOS 9/5/2023 <4.00 ppt 4.00 ppt Not Detected
PFUnA 9/5/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxS 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 9/5/2023 <6.00 ppt 6.00 ppt Not Detected
NEtFOSAA 9/5/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/5/2023 <7.00 ppt 7.00 ppt Not Detected
PFTA 9/5/2023 <8.00 ppt 8.00 ppt Not Detected
PFHpS 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFOA 9/5/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 9/5/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/5/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/5/2023 <4.00 ppt 4.00 ppt Not Detected
PFEESA 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/5/2023 <20.00 ppt 20.00 ppt Not Detected
4:2 FTS 9/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFOS 6/5/2023 <4.00 ppt 4.00 ppt Not Detected
NMeFOSAA 6/5/2023 <6.00 ppt 6.00 ppt Not Detected
PFTA 6/5/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 6/5/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 6/5/2023 <5.00 ppt 5.00 ppt Not Detected
PFBS 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 6/5/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 6/5/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 6/5/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 6/5/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeA 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 6/5/2023 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 6/5/2023 <2.00 ppt 2.00 ppt Not Detected
PFMPA 6/5/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 6/5/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 6/5/2023 <3.00 ppt 3.00 ppt Not Detected

UCMR5 PFAS record for Millis Water Dept

Open EPA SDWIS federal reports for PWS MA2187000 to cross-check UCMR5 detections and violation codes; state primacy agencies enforce the Safe Drinking Water Act locally.

Sources: EPA SDWIS · MassDEP, Drinking Water Program

Nationwide peers

98 violations · 9,002 served: nearest cross-state SDWIS matches.

What to do with Millis Water Dept

Use this system's EPA-reported record as a starting filter, not a final verdict.

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater