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States → New Mexico

Community Water System · PWS NM3506829

Questa Water System

Questa, New Mexico 87556 - drinking water served from groundwater sources to 2,337 people, tracked in EPA SDWIS and UCMR5.

2,337
People served
141
EPA violations
49
Health-based
Untested
UCMR5 result

The verdict

EPA records 141 drinking-water violations at Questa Water System, 35% of them health-based - below the New Mexico per-system average.

141
Total EPA violations on record
35%
Health-based (MCL / treatment failure)
2,337
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Questa Water System

Questa Water System is a local-owned community water system that delivers drinking water to 2,337 residents in Questa, New Mexico (Taos County) through 820 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 141 total violations for this system , of which 49 (35%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 62 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 29 violations (MCL, health-based). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across New Mexico, EPA tracks 1,037 public water systems serving 2,027,497 people, with 154,522 cumulative violations and 38,650 health-based violations on record. About 97% of systems in the state carry at least one violation, and state-wide the average per system is 149 violations. Statewide, 70 of 72 UCMR5-tested systems have reported PFAS detections (97.2%).

Questa Water System's 141 violations sit below the New Mexico average.

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
2,337
Total Violations
141
Health-Based Violations
49
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
820
County
Taos
School/Daycare
No
MCL Violations
29
Monitoring Violations
62
Treatment Tech Violations
20

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 29 2011
Groundwater Rule TT 20 2016
Coliform (TCR) MR 14 2012
Revised Total Coliform Rule MON 12 2018
Consumer Confidence Rule Other 10 2012
Chlorine MR 9 2012
TTHM MR 8 2016
Total Haloacetic Acids (HAA5) MR 8 2016
Lead and Copper Rule MR 7 2024
E. COLI MR 4 2018
Public Notice Other 4 2019
Revised Total Coliform Rule Other 4 2016

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 Questa Water System.

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 NM3506829 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

New Mexico Drinking Water Authority

New Mexico'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 NM 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
2024 Lead and Copper Rule MR 7 SDWIS / NM3506829 / 5000
2019 Public Notice Other 4 SDWIS / NM3506829 / 7500
2018 Revised Total Coliform Rule MON 12 SDWIS / NM3506829 / 8000
2018 E. COLI MR 4 SDWIS / NM3506829 / 3014
2016 Groundwater Rule TT 20 SDWIS / NM3506829 / 0700
2016 TTHM MR 8 SDWIS / NM3506829 / 2950
2016 Total Haloacetic Acids (HAA5) MR 8 SDWIS / NM3506829 / 2456
2016 Revised Total Coliform Rule Other 4 SDWIS / NM3506829 / 8000
2012 Coliform (TCR) MR 14 SDWIS / NM3506829 / 3100
2012 Consumer Confidence Rule Other 10 SDWIS / NM3506829 / 7000
2012 Chlorine MR 9 SDWIS / NM3506829 / 0999
2011 Coliform (TCR) MCL 29 SDWIS / NM3506829 / 3100

How Questa Water System Compares

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

Metric Questa Water System New Mexico avg Federal benchmark
Total violations 141 149 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 49 37.3 Indicates a contaminant exceeded a federal MCL
PFAS detection None 97.2% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,337 1,955 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 1,037 regulated public water systems in New Mexico.

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 Questa Water System water safe to drink? ▼
Questa Water System (PWS ID: NM3506829) has 141 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,337 people using Groundwater sources.
How many people does Questa Water System serve? ▼
Questa Water System serves 2,337 people in Questa, New Mexico. It is a Local-owned system using Groundwater water sources with 820 service connections.
What type of violations does Questa Water System have? ▼
Questa Water System has 141 total violations: 49 health-based violations (MCL exceedances or treatment failures), 62 monitoring/reporting violations, and 20 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Questa Water System water? ▼
No PFAS testing data is available for Questa Water System under the EPA's UCMR5 monitoring program.
What water source does Questa Water System use? ▼
Questa Water System uses Groundwater 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. 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.