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States → New Mexico

Community Water System · PWS NM3505529

Arroyo Seco Mdwca

Arroyo Seco, New Mexico 87514 - drinking water served from groundwater sources to 444 people, tracked in EPA SDWIS and UCMR5.

444
People served
182
EPA violations
19
Health-based
Untested
UCMR5 result

The verdict

EPA records 182 drinking-water violations at Arroyo Seco Mdwca, 10% of them health-based - above the New Mexico per-system average.

182
Total EPA violations on record
10%
Health-based (MCL / treatment failure)
444
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Arroyo Seco Mdwca

Arroyo Seco Mdwca is a local-owned community water system that delivers drinking water to 444 residents in Arroyo Seco, New Mexico (Taos County) through 182 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 182 total violations for this system , of which 19 (10%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 76 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Consumer Confidence Rule, recorded in 49 violations (Other). 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%).

Arroyo Seco Mdwca's 182 violations sit above 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
444
Total Violations
182
Health-Based Violations
19
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
182
County
Taos
School/Daycare
No
MCL Violations
16
Monitoring Violations
76
Treatment Tech Violations
3

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Consumer Confidence Rule Other 49 2025
Coliform (TCR) MR 41 2006
Coliform (TCR) MCL 16 2002
Total Haloacetic Acids (HAA5) MR 12 2022
TTHM MR 12 2022
Lead and Copper Rule MR 8 2015
Coliform (TCR) Other 7 1994
LEAD AND COPPER RULE REVISIONS RPT 3 2024
LEAD AND COPPER RULE REVISIONS TT 3 2024
Public Notice Other 2 2007
ETHYLENE DIBROMIDE MR 2 2005
Coliform (Pre-TCR) Other 2 1990
Nitrate MR 1 2000

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 Arroyo Seco Mdwca.

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 NM3505529 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
2025 Consumer Confidence Rule Other 49 SDWIS / NM3505529 / 7000
2024 LEAD AND COPPER RULE REVISIONS RPT 3 SDWIS / NM3505529 / 5200
2024 LEAD AND COPPER RULE REVISIONS TT 3 SDWIS / NM3505529 / 5200
2022 Total Haloacetic Acids (HAA5) MR 12 SDWIS / NM3505529 / 2456
2022 TTHM MR 12 SDWIS / NM3505529 / 2950
2015 Lead and Copper Rule MR 8 SDWIS / NM3505529 / 5000
2007 Public Notice Other 2 SDWIS / NM3505529 / 7500
2006 Coliform (TCR) MR 41 SDWIS / NM3505529 / 3100
2005 ETHYLENE DIBROMIDE MR 2 SDWIS / NM3505529 / 2946
2002 Coliform (TCR) MCL 16 SDWIS / NM3505529 / 3100
2000 Nitrate MR 1 SDWIS / NM3505529 / 1040
1994 Coliform (TCR) Other 7 SDWIS / NM3505529 / 3100
1990 Coliform (Pre-TCR) Other 2 SDWIS / NM3505529 / 3000

How Arroyo Seco Mdwca Compares

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

Metric Arroyo Seco Mdwca New Mexico avg Federal benchmark
Total violations 182 149 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 19 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 444 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 Arroyo Seco Mdwca water safe to drink? ▼
Arroyo Seco Mdwca (PWS ID: NM3505529) has 182 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 444 people using Groundwater sources.
How many people does Arroyo Seco Mdwca serve? ▼
Arroyo Seco Mdwca serves 444 people in Arroyo Seco, New Mexico. It is a Local-owned system using Groundwater water sources with 182 service connections.
What type of violations does Arroyo Seco Mdwca have? ▼
Arroyo Seco Mdwca has 182 total violations: 19 health-based violations (MCL exceedances or treatment failures), 76 monitoring/reporting violations, and 3 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Arroyo Seco Mdwca water? ▼
No PFAS testing data is available for Arroyo Seco Mdwca under the EPA's UCMR5 monitoring program.
What water source does Arroyo Seco Mdwca use? ▼
Arroyo Seco Mdwca 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.