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LAS MARIAS

PWS ID: PR0003363 · LAS MARIAS, Puerto Rico 00670

LAS MARIAS serves 7,166 people in LAS MARIAS, Puerto Rico using Surface Water water sources. It has 206 recorded EPA violations, including 34 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: LAS MARIAS

LAS MARIAS is a local-owned community water system that delivers drinking water to 7,166 residents in LAS MARIAS, Puerto Rico (Las Marias Municipio County) through 2,684 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 206 total violations for this system , of which 34 (17%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 159 monitoring and reporting violations are on file. The most recent violation on record dates to 2023.

The most frequently cited contaminant at this system is Cryptosporidium, recorded in 19 violations (MR). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

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. LAS MARIAS's 206 violations sit below the Puerto Rico average. Statewide, 40 of 99 UCMR5-tested systems have reported PFAS detections (40.4%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
7,166
Total Violations
206
Health-Based Violations
34
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
2,684
County
Las Marias Municipio
School/Daycare
No
MCL Violations
16
Monitoring Violations
159
Treatment Tech Violations
18

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Cryptosporidium MR 19 2018
E. COLI MR 17 2018
Turbidity MR 17 2018
Surface Water Treatment Rule TT 13 2001
Lead and Copper Rule MR 10 2015
TTHM MCL 10 2016
TTHM MR 7 2018
Coliform (TCR) MCL 6 2013
Total Haloacetic Acids (HAA5) MR 6 2018
Interim Enhanced Surface Water Treatment Rule TT 5 2023
Coliform (TCR) MR 4 2006
Consumer Confidence Rule Other 4 2020
Benzo(a)pyrene MR 3 2012
Nitrate MR 3 2006
Di(2-ethylhexyl) adipate MR 3 2012
LASSO MR 3 2012
Di(2-ethylhexyl) phthalate MR 3 2012
Atrazine MR 3 2012
Simazine MR 3 2012
1,2,4-Trichlorobenzene MR 2 2005
cis-1,2-Dichloroethylene MR 2 2005
Xylenes, Total MR 2 2005
o-Dichlorobenzene MR 2 2005
Vinyl chloride MR 2 2005
1,1-Dichloroethylene MR 2 2005
1,2-Dichloroethane MR 2 2005
1,1,1-Trichloroethane MR 2 2005
Carbon tetrachloride MR 2 2005
1,2-Dichloropropane MR 2 2005
Styrene MR 2 2005

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 120 samples detected PFAS.

Contaminant Date Result MRL Status
11Cl-PF3OUdS 8/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 8/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFDA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 8/20/2024 <0.002 µg/L 0.002 µg/L Not Detected
PFOA 8/20/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFOS 8/20/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFNA 8/20/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFHpA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
lithium 8/20/2024 <9 µg/L 9 µg/L Not Detected
9Cl-PF3ONS 8/20/2024 <0.002 µg/L 0.002 µg/L Not Detected
PFPeS 8/20/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFHxS 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFTA 8/20/2024 <0.008 µg/L 0.008 µg/L Not Detected
PFTrDA 8/20/2024 <0.007 µg/L 0.007 µg/L Not Detected
NEtFOSAA 8/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
NMeFOSAA 8/20/2024 <0.006 µg/L 0.006 µg/L Not Detected
PFHpS 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFEESA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFBS 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
ADONA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMPA 8/20/2024 <0.004 µg/L 0.004 µg/L Not Detected
8:2 FTS 8/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 8/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFBA 8/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
HFPO-DA 8/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
NFDHA 8/20/2024 <0.02 µg/L 0.02 µg/L Not Detected
lithium 5/20/2024 <9 µg/L 9 µg/L Not Detected
PFMBA 5/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
NMeFOSAA 5/20/2024 <0.006 µg/L 0.006 µg/L Not Detected
NEtFOSAA 5/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFTrDA 5/20/2024 <0.007 µg/L 0.007 µg/L Not Detected
PFTA 5/20/2024 <0.008 µg/L 0.008 µg/L Not Detected
PFBA 5/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
HFPO-DA 5/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 5/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFUnA 5/20/2024 <0.002 µg/L 0.002 µg/L Not Detected
PFOA 5/20/2024 <0.004 µg/L 0.004 µg/L Not Detected
NFDHA 5/20/2024 <0.02 µg/L 0.02 µg/L Not Detected
PFDA 5/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 5/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
11Cl-PF3OUdS 5/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
9Cl-PF3ONS 5/20/2024 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 5/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
4:2 FTS 5/20/2024 <0.003 µg/L 0.003 µg/L Not Detected
8:2 FTS 5/20/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFHpA 5/20/2024 <0.003 µg/L 0.003 µg/L 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 MARIAS.

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 PR0003363 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
2023 Interim Enhanced Surface Water Treatment Rule TT 5 SDWIS / PR0003363 / 0300
2020 Consumer Confidence Rule Other 4 SDWIS / PR0003363 / 7000
2018 Cryptosporidium MR 19 SDWIS / PR0003363 / 3015
2018 E. COLI MR 17 SDWIS / PR0003363 / 3014
2018 Turbidity MR 17 SDWIS / PR0003363 / 0100
2018 TTHM MR 7 SDWIS / PR0003363 / 2950
2018 Total Haloacetic Acids (HAA5) MR 6 SDWIS / PR0003363 / 2456
2016 TTHM MCL 10 SDWIS / PR0003363 / 2950
2015 Lead and Copper Rule MR 10 SDWIS / PR0003363 / 5000
2013 Coliform (TCR) MCL 6 SDWIS / PR0003363 / 3100
2012 Benzo(a)pyrene MR 3 SDWIS / PR0003363 / 2306
2012 Di(2-ethylhexyl) adipate MR 3 SDWIS / PR0003363 / 2035
2012 LASSO MR 3 SDWIS / PR0003363 / 2051
2012 Di(2-ethylhexyl) phthalate MR 3 SDWIS / PR0003363 / 2039
2012 Atrazine MR 3 SDWIS / PR0003363 / 2050

How LAS MARIAS Compares

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

Metric LAS MARIAS Puerto Rico avg Federal benchmark
Total violations 206 358.4 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 34 75.7 Indicates a contaminant exceeded a federal MCL
PFAS detection None 40.4% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 7,166 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
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is LAS MARIAS water safe to drink? ▼
LAS MARIAS (PWS ID: PR0003363) has 206 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 7,166 people using Surface Water sources.
How many people does LAS MARIAS serve? ▼
LAS MARIAS serves 7,166 people in LAS MARIAS, Puerto Rico. It is a Local-owned system using Surface Water water sources with 2,684 service connections.
What type of violations does LAS MARIAS have? ▼
LAS MARIAS has 206 total violations: 34 health-based violations (MCL exceedances or treatment failures), 159 monitoring/reporting violations, and 18 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in LAS MARIAS water? ▼
No. LAS MARIAS was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does LAS MARIAS use? ▼
LAS MARIAS 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.

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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.

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Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by Kiznis Studio Editorial