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Community Water System · PWS PR0005597

Maguayo

Dorado, Puerto Rico 00646 - drinking water served from surface water sources to 31,880 people, tracked in EPA SDWIS and UCMR5.

31,880
People served
583
EPA violations
10
Health-based
1 PFAS
UCMR5 result

The verdict

EPA records 583 drinking-water violations at Maguayo, 2% of them health-based - above the Puerto Rico per-system average, and UCMR5 testing detected 1 PFAS compound.

583
Total EPA violations on record
2%
Health-based (MCL / treatment failure)
31,880
People served by this system
1
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Maguayo

Maguayo is a local-owned community water system that delivers drinking water to 31,880 residents in Dorado, Puerto Rico (Dorado Municipio County) through 11,940 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 583 total violations for this system , of which 10 (2%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 564 monitoring and reporting violations are on file. The most recent violation on record dates to 2020.

The most frequently cited contaminant at this system is Benzo(a)pyrene, recorded in 14 violations (MR). Under EPA's UCMR5 PFAS monitoring program, 1 PFAS compound was detected in samples collected from this system, with a maximum reported concentration of 6.7 ppt (parts per trillion). PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

Across Puerto Rico, EPA tracks 458 public water systems serving 3,328,141 people, with 164,144 cumulative violations and 34,657 health-based violations on record. About 100% of systems in the state carry at least one violation, and state-wide the average per system is 358.4 violations. Statewide, 40 of 99 UCMR5-tested systems have reported PFAS detections (40.4%).

Maguayo's 583 violations sit above the Puerto Rico average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

PFAS Detected

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

Population Served
31,880
Total Violations
583
Health-Based Violations
10
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
11,940
County
Dorado Municipio
School/Daycare
No
MCL Violations
10
Monitoring Violations
564
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Benzo(a)pyrene MR 14 2014
Chlordane MR 14 2012
Endrin MR 14 2012
Heptachlor epoxide MR 14 2012
Methoxychlor MR 14 2012
Total Polychlorinated Biphenyls (PCB) MR 14 2012
BHC-GAMMA MR 14 2012
Toxaphene MR 14 2012
Heptachlor MR 14 2012
Di(2-ethylhexyl) adipate MR 14 2014
Di(2-ethylhexyl) phthalate MR 14 2014
HEXACHLOROBENZENE MR 14 2012
Glyphosate MR 13 2012
2,4,5-TP MR 12 2012
LASSO MR 12 2012
Dalapon MR 12 2012
Hexachlorocyclopentadiene MR 12 2012
Pentachlorophenol MR 12 2012
Picloram MR 12 2012
Nitrite MR 12 2011
Endothall MR 12 2012
OXAMYL MR 12 2012
Simazine MR 12 2012
Dinoseb MR 12 2012
Atrazine MR 12 2012
2,4-D MR 12 2012
1,2-DIBROMO-3-CHLOROPROPANE MR 12 2012
ETHYLENE DIBROMIDE MR 12 2012
Carbofuran MR 12 2012
Diquat MR 12 2012

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 1 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
PFEESA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 7/26/2023 <5.00 ppt 5.00 ppt Not Detected
ADONA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 7/26/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 7/26/2023 6.70 ppt 5.00 ppt Detected
11Cl-PF3OUdS 7/26/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 7/26/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 7/26/2023 <4.00 ppt 4.00 ppt Not Detected
PFMBA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 7/26/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 7/26/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 7/26/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 7/26/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 7/26/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 7/26/2023 <2.00 ppt 2.00 ppt Not Detected
NMeFOSAA 7/26/2023 <6.00 ppt 6.00 ppt Not Detected
PFBS 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 7/26/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 7/26/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 7/26/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpS 7/26/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 7/26/2023 <2.00 ppt 2.00 ppt Not Detected
PFOA 4/24/2023 <4.00 ppt 4.00 ppt Not Detected
PFMBA 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 4/24/2023 <6.00 ppt 6.00 ppt Not Detected
NEtFOSAA 4/24/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 4/24/2023 <7.00 ppt 7.00 ppt Not Detected
PFHpS 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 4/24/2023 <4.00 ppt 4.00 ppt Not Detected
PFDoA 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 4/24/2023 <8.00 ppt 8.00 ppt Not Detected
PFPeA 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 4/24/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 4/24/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 4/24/2023 <5.00 ppt 5.00 ppt Not Detected
PFOS 4/24/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpA 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 4/24/2023 <20.00 ppt 20.00 ppt Not Detected
PFBS 4/24/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 4/24/2023 <4.00 ppt 4.00 ppt Not Detected

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Maguayo.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID PR0005597 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Puerto Rico Drinking Water Authority

Puerto Rico's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find PR regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2020 Consumer Confidence Rule Other 4 SDWIS / PR0005597 / 7000
2016 TTHM MR 4 SDWIS / PR0005597 / 2950
2016 Total Haloacetic Acids (HAA5) MR 4 SDWIS / PR0005597 / 2456
2016 Lead and Copper Rule MR 4 SDWIS / PR0005597 / 5000
2015 Coliform (TCR) MCL 10 SDWIS / PR0005597 / 3100
2014 Benzo(a)pyrene MR 14 SDWIS / PR0005597 / 2306
2014 Di(2-ethylhexyl) adipate MR 14 SDWIS / PR0005597 / 2035
2014 Di(2-ethylhexyl) phthalate MR 14 SDWIS / PR0005597 / 2039
2012 Chlordane MR 14 SDWIS / PR0005597 / 2959
2012 Endrin MR 14 SDWIS / PR0005597 / 2005
2012 Heptachlor epoxide MR 14 SDWIS / PR0005597 / 2067
2012 Methoxychlor MR 14 SDWIS / PR0005597 / 2015
2012 Total Polychlorinated Biphenyls (PCB) MR 14 SDWIS / PR0005597 / 2383
2012 BHC-GAMMA MR 14 SDWIS / PR0005597 / 2010
2012 Toxaphene MR 14 SDWIS / PR0005597 / 2020

How Maguayo Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Maguayo Puerto Rico avg Federal benchmark
Total violations 583 358.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 10 75.7 Indicates a contaminant exceeded a federal MCL
PFAS detection 1 compound 40.4% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 31,880 7,267 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 458 regulated public water systems in Puerto Rico.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Maguayo water safe to drink? ▼
Maguayo (PWS ID: PR0005597) has 583 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 1 PFAS compound found. This system serves 31,880 people using Surface Water sources.
How many people does Maguayo serve? ▼
Maguayo serves 31,880 people in Dorado, Puerto Rico. It is a Local-owned system using Surface Water water sources with 11,940 service connections.
What type of violations does Maguayo have? ▼
Maguayo has 583 total violations: 10 health-based violations (MCL exceedances or treatment failures), 564 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Maguayo water? ▼
Yes. UCMR5 testing detected 1 PFAS compound in Maguayo's water supply: PFBA. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does Maguayo use? ▼
Maguayo uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

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

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.