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Community Water System · PWS PR0005376

Las Piedras Humacao

Humacao, Puerto Rico 00791 - drinking water served from surface water sources to 36,032 people, tracked in EPA SDWIS and UCMR5.

36,032
People served
259
EPA violations
113
Health-based
1 PFAS
UCMR5 result

The verdict

EPA records 259 drinking-water violations at Las Piedras Humacao, 44% of them health-based - below the Puerto Rico per-system average, and UCMR5 testing detected 1 PFAS compound.

259
Total EPA violations on record
44%
Health-based (MCL / treatment failure)
36,032
People served by this system
1
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Las Piedras Humacao

Las Piedras Humacao is a local-owned community water system that delivers drinking water to 36,032 residents in Humacao, Puerto Rico (Humacao Municipio County) through 13,495 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 259 total violations for this system , of which 113 (44%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 130 monitoring and reporting violations are on file. The most recent violation on record dates to 2022.

The most frequently cited contaminant at this system is Interim Enhanced Surface Water Treatment Rule, recorded in 99 violations (TT, health-based). Under EPA's UCMR5 PFAS monitoring program, 1 PFAS compound was detected in samples collected from this system, with a maximum reported concentration of 5.4 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%).

Las Piedras Humacao's 259 violations sit below 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
36,032
Total Violations
259
Health-Based Violations
113
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
13,495
County
Humacao Municipio
School/Daycare
No
MCL Violations
5
Monitoring Violations
130
Treatment Tech Violations
108

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Interim Enhanced Surface Water Treatment Rule TT 99 2010
Cryptosporidium MR 27 2019
Turbidity MR 23 2019
E. COLI MR 23 2019
Lead and Copper Rule MR 18 2015
CARBON, TOTAL TT 9 2008
Coliform (TCR) MR 7 2014
Coliform (TCR) MCL 5 2015
Consumer Confidence Rule Other 4 2020
Surface Water Treatment Rule MR 3 2022
TTHM MR 2 2014
Antimony, Total MR 2 2014
Carbofuran MR 2 2021
OXAMYL MR 2 2021
Mercury MR 2 1984
Nitrate MR 2 1984
Barium MR 2 1984
Arsenic MR 2 1984
Fluoride MR 2 1984
Cadmium MR 2 1984
Selenium MR 2 1984
Chromium MR 2 1984
Public Notice Other 2 2019
Total Haloacetic Acids (HAA5) MR 2 2014
Combined Radium (-226 and -228) MR 1 1980
Gross Alpha, Excl. Radon and U MR 1 1980
Interim Enhanced Surface Water Treatment Rule MR 1 2004

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 3 of 174 samples detected PFAS.

Contaminant Date Result MRL Status
ADONA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFTA 7/30/2024 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 7/30/2024 <7.00 ppt 7.00 ppt Not Detected
11Cl-PF3OUdS 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 7/30/2024 <6.00 ppt 6.00 ppt Not Detected
PFBS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
NFDHA 7/30/2024 <20.00 ppt 20.00 ppt Not Detected
PFEESA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFOS 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
NEtFOSAA 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
PFHxS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
PFHpA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFOA 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
PFDA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 7/30/2024 <2.00 ppt 2.00 ppt Not Detected
9Cl-PF3ONS 7/30/2024 <2.00 ppt 2.00 ppt Not Detected
PFDoA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFBA 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
PFTA 7/30/2024 <8.00 ppt 8.00 ppt Not Detected
PFPeA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFOA 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 7/30/2024 5.20 ppt 4.00 ppt Detected
PFHxS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFBS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 7/30/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 7/30/2024 <2.00 ppt 2.00 ppt Not Detected
4:2 FTS 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
PFNA 7/30/2024 <4.00 ppt 4.00 ppt Not Detected
PFMBA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
PFBA 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
ADONA 7/30/2024 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 7/30/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 7/30/2024 <6.00 ppt 6.00 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 Las Piedras Humacao.

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 PR0005376 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
2022 Surface Water Treatment Rule MR 3 SDWIS / PR0005376 / 0200
2021 Carbofuran MR 2 SDWIS / PR0005376 / 2046
2021 OXAMYL MR 2 SDWIS / PR0005376 / 2036
2020 Consumer Confidence Rule Other 4 SDWIS / PR0005376 / 7000
2019 Cryptosporidium MR 27 SDWIS / PR0005376 / 3015
2019 Turbidity MR 23 SDWIS / PR0005376 / 0100
2019 E. COLI MR 23 SDWIS / PR0005376 / 3014
2019 Public Notice Other 2 SDWIS / PR0005376 / 7500
2015 Lead and Copper Rule MR 18 SDWIS / PR0005376 / 5000
2015 Coliform (TCR) MCL 5 SDWIS / PR0005376 / 3100
2014 Coliform (TCR) MR 7 SDWIS / PR0005376 / 3100
2014 TTHM MR 2 SDWIS / PR0005376 / 2950
2014 Antimony, Total MR 2 SDWIS / PR0005376 / 1074
2014 Total Haloacetic Acids (HAA5) MR 2 SDWIS / PR0005376 / 2456
2010 Interim Enhanced Surface Water Treatment Rule TT 99 SDWIS / PR0005376 / 0300

How Las Piedras Humacao Compares

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

Metric Las Piedras Humacao Puerto Rico avg Federal benchmark
Total violations 259 358.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 113 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 36,032 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 Las Piedras Humacao water safe to drink? ▼
Las Piedras Humacao (PWS ID: PR0005376) has 259 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 1 PFAS compound found. This system serves 36,032 people using Surface Water sources.
How many people does Las Piedras Humacao serve? ▼
Las Piedras Humacao serves 36,032 people in Humacao, Puerto Rico. It is a Local-owned system using Surface Water water sources with 13,495 service connections.
What type of violations does Las Piedras Humacao have? ▼
Las Piedras Humacao has 259 total violations: 113 health-based violations (MCL exceedances or treatment failures), 130 monitoring/reporting violations, and 108 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Las Piedras Humacao water? ▼
Yes. UCMR5 testing detected 1 PFAS compound in Las Piedras Humacao's water supply: PFOS. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does Las Piedras Humacao use? ▼
Las Piedras Humacao 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.