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Community Water System · PWS PR0003283

Mayaguez

Operator location Mayaguez, Puerto Rico - larger served population (> 3,309) at 151,555 people served; 1,188 SDWIS violations on record from surface water sources.

151,555
People served (this PWS)
1,188
EPA violations (this PWS)
193
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Mayaguez standing, high SDWIS violation third

151,555 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 16% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #291 of 29,740 among systems serving 500+.

The verdict

Mayaguez sits in the upper third of the sitemap cohort by violation count (1,188), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (151,555; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 16% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#291 of 29,740
Population · /systems
#2 of 235
Population · PR
1,188
Total EPA violations on record
16%
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
56,762
County
Mayaguez Municipio
School/Daycare
No
MCL Violations
55
Monitoring Violations
967
Treatment Tech Violations
138

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Surface Water Treatment Rule TT 82 2001
Turbidity MR 53 2017
Cryptosporidium MR 53 2017
E. COLI MR 53 2017
Interim Enhanced Surface Water Treatment Rule TT 36 2022
TTHM MCL 27 2018
Total Haloacetic Acids (HAA5) MCL 24 2016
Di(2-ethylhexyl) adipate MR 21 2018
Simazine MR 21 2018
Di(2-ethylhexyl) phthalate MR 21 2018
Benzo(a)pyrene MR 21 2018
Atrazine MR 21 2018
LASSO MR 21 2018
Endrin MR 20 2019
BHC-GAMMA MR 20 2019
Methoxychlor MR 20 2019
Heptachlor epoxide MR 20 2019
HEXACHLOROBENZENE MR 20 2019
Toxaphene MR 19 2018
Heptachlor MR 19 2019
Chlordane MR 19 2018
Hexachlorocyclopentadiene MR 18 2019
CARBON, TOTAL TT 18 2011
ETHYLENE DIBROMIDE MR 17 2021
1,2-DIBROMO-3-CHLOROPROPANE MR 17 2021
Carbofuran MR 15 2018
Total Polychlorinated Biphenyls (PCB) MR 15 2018
OXAMYL MR 15 2018
Dinoseb MR 13 2018
2,4,5-TP MR 13 2018

Violation Count vs. the National Corpus

Mayaguez has 1,188 recorded EPA violations, 99% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 1% carry more. 16% of this system's own violations are health-based (193 of 1,188), and it ranks #291 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)

1,188 Higher than most more violations than 99% 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 696 samples detected PFAS.

Contaminant Date Result MRL Status
PFPeS 9/9/2025 <4.00 ppt 4.00 ppt Not Detected
PFBA 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/9/2025 <4.00 ppt 4.00 ppt Not Detected
PFPeA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/9/2025 <20.00 ppt 20.00 ppt Not Detected
HFPO-DA 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFDA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFEESA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFHxA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 9/9/2025 <7.00 ppt 7.00 ppt Not Detected
ADONA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 9/9/2025 <6.00 ppt 6.00 ppt Not Detected
PFHpS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFTA 9/9/2025 <8.00 ppt 8.00 ppt Not Detected
PFNA 9/9/2025 <4.00 ppt 4.00 ppt Not Detected
9Cl-PF3ONS 9/9/2025 <2.00 ppt 2.00 ppt Not Detected
PFUnA 9/9/2025 <2.00 ppt 2.00 ppt Not Detected
PFDoA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFOA 9/9/2025 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/9/2025 <4.00 ppt 4.00 ppt Not Detected
6:2 FTS 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/9/2025 <7.00 ppt 7.00 ppt Not Detected
PFBA 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFMBA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/9/2025 <4.00 ppt 4.00 ppt Not Detected
PFPeA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFEESA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/9/2025 <20.00 ppt 20.00 ppt Not Detected
PFTA 9/9/2025 <8.00 ppt 8.00 ppt Not Detected
NEtFOSAA 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/9/2025 <6.00 ppt 6.00 ppt Not Detected
HFPO-DA 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
11Cl-PF3OUdS 9/9/2025 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
ADONA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/9/2025 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/9/2025 <4.00 ppt 4.00 ppt Not Detected

Population served record for Mayaguez

EPA SDWIS lists 151,555 people served and 56,762 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS

Nationwide peers

1,188 violations · 151,555 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.

4 peers

Cross-state systems with similar served population

Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).

4 peers

What to do with Mayaguez

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

  • See how every tracked system in Puerto Rico compares on the same EPA violation measures. Puerto Rico 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.

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