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States → EPA Region 6 — Tribal Water Systems

Community Water System · PWS 063500116

San Ildefonso Pueblo

Santa Fe, EPA Region 6 — Tribal Water Systems 87506 - drinking water served from groundwater sources to 608 people, tracked in EPA SDWIS and UCMR5.

608
People served
56
EPA violations
20
Health-based
Untested
UCMR5 result

The verdict

EPA records 56 drinking-water violations at San Ildefonso Pueblo, 36% of them health-based.

56
Total EPA violations on record
36%
Health-based (MCL / treatment failure)
608
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: San Ildefonso Pueblo

San Ildefonso Pueblo is a native american-owned community water system that delivers drinking water to 608 residents in Santa Fe, EPA Region 6 — Tribal Water Systems through 257 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 56 total violations for this system , of which 20 (36%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 22 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 16 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

EPA Region 6 — Tribal Water Systems has thousands of regulated public water systems tracked by EPA under the Safe Drinking Water Act.

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
608
Total Violations
56
Health-Based Violations
20
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Native American
Connections
257
School/Daycare
No
MCL Violations
2
Monitoring Violations
22
Treatment Tech Violations
18

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 16 2008
Groundwater Rule TT 16 2018
Consumer Confidence Rule Other 9 2005
Lead and Copper Rule MR 2 2008
Total Haloacetic Acids (HAA5) MR 2 2015
Stage 1 Disinfectants and Disinfection Byproducts Rule TT 2 2019
Coliform (TCR) MCL 2 1997
TTHM MR 2 2015
Public Notice Other 1 2013

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 San Ildefonso Pueblo.

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 063500116 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

EPA Region 6 — Tribal Water Systems Drinking Water Authority

EPA Region 6 — Tribal Water Systems'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 06 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 Stage 1 Disinfectants and Disinfection Byproducts Rule TT 2 SDWIS / 063500116 / 0400
2018 Groundwater Rule TT 16 SDWIS / 063500116 / 0700
2015 Total Haloacetic Acids (HAA5) MR 2 SDWIS / 063500116 / 2456
2015 TTHM MR 2 SDWIS / 063500116 / 2950
2013 Public Notice Other 1 SDWIS / 063500116 / 7500
2008 Coliform (TCR) MR 16 SDWIS / 063500116 / 3100
2008 Lead and Copper Rule MR 2 SDWIS / 063500116 / 5000
2005 Consumer Confidence Rule Other 9 SDWIS / 063500116 / 7000
1997 Coliform (TCR) MCL 2 SDWIS / 063500116 / 3100

How San Ildefonso Pueblo Compares

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

Metric San Ildefonso Pueblo EPA Region 6 — Tribal Water Systems avg Federal benchmark
Total violations 56 - SDWA compliance, any non-zero count is a recorded breach
Health-based violations 20 - Indicates a contaminant exceeded a federal MCL
PFAS detection None - EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 608 - Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across all regulated public water systems in EPA Region 6 — Tribal Water Systems.

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 San Ildefonso Pueblo water safe to drink? ▼
San Ildefonso Pueblo (PWS ID: 063500116) has 56 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 608 people using Groundwater sources.
How many people does San Ildefonso Pueblo serve? ▼
San Ildefonso Pueblo serves 608 people in Santa Fe, EPA Region 6 — Tribal Water Systems. It is a Native American-owned system using Groundwater water sources with 257 service connections.
What type of violations does San Ildefonso Pueblo have? ▼
San Ildefonso Pueblo has 56 total violations: 20 health-based violations (MCL exceedances or treatment failures), 22 monitoring/reporting violations, and 18 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in San Ildefonso Pueblo water? ▼
No PFAS testing data is available for San Ildefonso Pueblo under the EPA's UCMR5 monitoring program.
What water source does San Ildefonso Pueblo use? ▼
San Ildefonso Pueblo 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.