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States → New Mexico

Community Water System · PWS NM3519225

South San Ysidro Mdwca

Ribera, New Mexico 87560 - drinking water served from groundwater sources to 35 people, tracked in EPA SDWIS and UCMR5.

35
People served
69
EPA violations
32
Health-based
Untested
UCMR5 result

The verdict

EPA records 69 drinking-water violations at South San Ysidro Mdwca, 46% of them health-based - below the New Mexico per-system average.

69
Total EPA violations on record
46%
Health-based (MCL / treatment failure)
35
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: South San Ysidro Mdwca

South San Ysidro Mdwca is a local-owned community water system that delivers drinking water to 35 residents in Ribera, New Mexico (San Miguel County) through 16 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 69 total violations for this system , of which 32 (46%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 28 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 Groundwater Rule, recorded in 16 violations (TT, 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%).

South San Ysidro Mdwca's 69 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
35
Total Violations
69
Health-Based Violations
32
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
16
County
San Miguel
School/Daycare
No
MCL Violations
14
Monitoring Violations
28
Treatment Tech Violations
18

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Groundwater Rule TT 16 2018
Coliform (TCR) MCL 14 2014
Lead and Copper Rule MR 8 2019
Coliform (TCR) MR 8 2013
Revised Total Coliform Rule MON 8 2019
E. COLI MR 4 2013
Consumer Confidence Rule Other 4 2012
Public Notice Other 3 2019
LEAD AND COPPER RULE REVISIONS RPT 2 2024
LEAD AND COPPER RULE REVISIONS TT 2 2024

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 South San Ysidro 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 NM3519225 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 REVISIONS RPT 2 SDWIS / NM3519225 / 5200
2024 LEAD AND COPPER RULE REVISIONS TT 2 SDWIS / NM3519225 / 5200
2019 Lead and Copper Rule MR 8 SDWIS / NM3519225 / 5000
2019 Revised Total Coliform Rule MON 8 SDWIS / NM3519225 / 8000
2019 Public Notice Other 3 SDWIS / NM3519225 / 7500
2018 Groundwater Rule TT 16 SDWIS / NM3519225 / 0700
2014 Coliform (TCR) MCL 14 SDWIS / NM3519225 / 3100
2013 Coliform (TCR) MR 8 SDWIS / NM3519225 / 3100
2013 E. COLI MR 4 SDWIS / NM3519225 / 3014
2012 Consumer Confidence Rule Other 4 SDWIS / NM3519225 / 7000

How South San Ysidro Mdwca Compares

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

Metric South San Ysidro Mdwca New Mexico avg Federal benchmark
Total violations 69 149 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 32 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 35 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 South San Ysidro Mdwca water safe to drink? ▼
South San Ysidro Mdwca (PWS ID: NM3519225) has 69 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 35 people using Groundwater sources.
How many people does South San Ysidro Mdwca serve? ▼
South San Ysidro Mdwca serves 35 people in Ribera, New Mexico. It is a Local-owned system using Groundwater water sources with 16 service connections.
What type of violations does South San Ysidro Mdwca have? ▼
South San Ysidro Mdwca has 69 total violations: 32 health-based violations (MCL exceedances or treatment failures), 28 monitoring/reporting violations, and 18 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in South San Ysidro Mdwca water? ▼
No PFAS testing data is available for South San Ysidro Mdwca under the EPA's UCMR5 monitoring program.
What water source does South San Ysidro Mdwca use? ▼
South San Ysidro 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.