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States → New Mexico

Community Water System · PWS NM3505429

Lower Arroyo Hondo Mdwca

Arroyo Seco, New Mexico 87514 - drinking water served from groundwater sources to 180 people, tracked in EPA SDWIS and UCMR5.

180
People served
51
EPA violations
13
Health-based
Untested
UCMR5 result

The verdict

EPA records 51 drinking-water violations at Lower Arroyo Hondo Mdwca, 25% of them health-based - below the New Mexico per-system average.

51
Total EPA violations on record
25%
Health-based (MCL / treatment failure)
180
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Lower Arroyo Hondo Mdwca

Lower Arroyo Hondo Mdwca is a local-owned community water system that delivers drinking water to 180 residents in Arroyo Seco, New Mexico (Taos County) through 63 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 51 total violations for this system , of which 13 (25%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 18 monitoring and reporting violations are on file. The most recent violation on record dates to 2019.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 14 violations (MR). 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%).

Lower Arroyo Hondo Mdwca's 51 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
180
Total Violations
51
Health-Based Violations
13
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
63
County
Taos
School/Daycare
No
MCL Violations
0
Monitoring Violations
18
Treatment Tech Violations
13

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 14 1999
Groundwater Rule TT 13 2019
Consumer Confidence Rule Other 11 2012
Coliform (TCR) Other 4 1994
Nitrate-Nitrite MR 4 2005
Public Notice Other 3 2018
Coliform (Pre-TCR) Other 1 1990

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 Lower Arroyo Hondo 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 NM3505429 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
2019 Groundwater Rule TT 13 SDWIS / NM3505429 / 0700
2018 Public Notice Other 3 SDWIS / NM3505429 / 7500
2012 Consumer Confidence Rule Other 11 SDWIS / NM3505429 / 7000
2005 Nitrate-Nitrite MR 4 SDWIS / NM3505429 / 1038
1999 Coliform (TCR) MR 14 SDWIS / NM3505429 / 3100
1994 Coliform (TCR) Other 4 SDWIS / NM3505429 / 3100
1990 Coliform (Pre-TCR) Other 1 SDWIS / NM3505429 / 3000

How Lower Arroyo Hondo Mdwca Compares

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

Metric Lower Arroyo Hondo Mdwca New Mexico avg Federal benchmark
Total violations 51 149 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 13 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 180 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 Lower Arroyo Hondo Mdwca water safe to drink? ▼
Lower Arroyo Hondo Mdwca (PWS ID: NM3505429) has 51 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 180 people using Groundwater sources.
How many people does Lower Arroyo Hondo Mdwca serve? ▼
Lower Arroyo Hondo Mdwca serves 180 people in Arroyo Seco, New Mexico. It is a Local-owned system using Groundwater water sources with 63 service connections.
What type of violations does Lower Arroyo Hondo Mdwca have? ▼
Lower Arroyo Hondo Mdwca has 51 total violations: 13 health-based violations (MCL exceedances or treatment failures), 18 monitoring/reporting violations, and 13 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Lower Arroyo Hondo Mdwca water? ▼
No PFAS testing data is available for Lower Arroyo Hondo Mdwca under the EPA's UCMR5 monitoring program.
What water source does Lower Arroyo Hondo Mdwca use? ▼
Lower Arroyo Hondo 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.