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States → New Mexico

Community Water System · PWS NM3573725

Big Mesa Water Mdwca

Conchas Dam, New Mexico 88416 - drinking water served from surface water sources to 250 people, tracked in EPA SDWIS and UCMR5.

250
People served
332
EPA violations
82
Health-based
Untested
UCMR5 result

The verdict

EPA records 332 drinking-water violations at Big Mesa Water Mdwca, 25% of them health-based - above the New Mexico per-system average.

332
Total EPA violations on record
25%
Health-based (MCL / treatment failure)
250
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Big Mesa Water Mdwca

Big Mesa Water Mdwca is a local-owned community water system that delivers drinking water to 250 residents in Conchas Dam, New Mexico (San Miguel County) through 572 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 332 total violations for this system , of which 82 (25%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 230 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 Surface Water Treatment Rule, recorded in 87 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%).

Big Mesa Water Mdwca's 332 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
250
Total Violations
332
Health-Based Violations
82
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
572
County
San Miguel
School/Daycare
No
MCL Violations
78
Monitoring Violations
230
Treatment Tech Violations
4

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Surface Water Treatment Rule MR 87 2017
Interim Enhanced Surface Water Treatment Rule MR 68 2017
TTHM MCL 64 2024
Total Haloacetic Acids (HAA5) MR 16 2022
TTHM MR 16 2022
Coliform (TCR) MCL 14 2012
Lead and Copper Rule MR 14 2023
Chlorine MR 12 2010
Public Notice Other 11 2018
Asbestos MR 4 2020
Interim Enhanced Surface Water Treatment Rule TT 4 2016
Coliform (TCR) MR 2 1991
E. COLI MR 2 2008
Fluoride MR 2 1982
Nitrate MR 1 1980
Arsenic MR 1 1982
Chromium MR 1 1982
Selenium MR 1 1982
Cadmium MR 1 1982
Mercury MR 1 1982
Barium MR 1 1982

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 Big Mesa Water 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 NM3573725 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 TTHM MCL 64 SDWIS / NM3573725 / 2950
2023 Lead and Copper Rule MR 14 SDWIS / NM3573725 / 5000
2022 Total Haloacetic Acids (HAA5) MR 16 SDWIS / NM3573725 / 2456
2022 TTHM MR 16 SDWIS / NM3573725 / 2950
2020 Asbestos MR 4 SDWIS / NM3573725 / 1094
2018 Public Notice Other 11 SDWIS / NM3573725 / 7500
2017 Surface Water Treatment Rule MR 87 SDWIS / NM3573725 / 0200
2017 Interim Enhanced Surface Water Treatment Rule MR 68 SDWIS / NM3573725 / 0300
2016 Interim Enhanced Surface Water Treatment Rule TT 4 SDWIS / NM3573725 / 0300
2012 Coliform (TCR) MCL 14 SDWIS / NM3573725 / 3100
2010 Chlorine MR 12 SDWIS / NM3573725 / 0999
2008 E. COLI MR 2 SDWIS / NM3573725 / 3014
1991 Coliform (TCR) MR 2 SDWIS / NM3573725 / 3100
1982 Fluoride MR 2 SDWIS / NM3573725 / 1025
1982 Arsenic MR 1 SDWIS / NM3573725 / 1005

How Big Mesa Water Mdwca Compares

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

Metric Big Mesa Water Mdwca New Mexico avg Federal benchmark
Total violations 332 149 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 82 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 250 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 Big Mesa Water Mdwca water safe to drink? ▼
Big Mesa Water Mdwca (PWS ID: NM3573725) has 332 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 250 people using Surface Water sources.
How many people does Big Mesa Water Mdwca serve? ▼
Big Mesa Water Mdwca serves 250 people in Conchas Dam, New Mexico. It is a Local-owned system using Surface Water water sources with 572 service connections.
What type of violations does Big Mesa Water Mdwca have? ▼
Big Mesa Water Mdwca has 332 total violations: 82 health-based violations (MCL exceedances or treatment failures), 230 monitoring/reporting violations, and 4 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Big Mesa Water Mdwca water? ▼
No PFAS testing data is available for Big Mesa Water Mdwca under the EPA's UCMR5 monitoring program.
What water source does Big Mesa Water Mdwca use? ▼
Big Mesa Water Mdwca 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. 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.