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Community Water System · PWS NN0433001

Tuba City Boarding School BIA

Tuba City, Navajo Nation 86045 - drinking water served from groundwater sources to 2,040 people, tracked in EPA SDWIS and UCMR5.

2,040
People served
35
EPA violations
1
Health-based
Untested
UCMR5 result

The verdict

EPA records 35 drinking-water violations at Tuba City Boarding School BIA, 3% of them health-based - below the Navajo Nation per-system average.

35
Total EPA violations on record
3%
Health-based (MCL / treatment failure)
2,040
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Tuba City Boarding School BIA

Tuba City Boarding School BIA is a federal-owned community water system that delivers drinking water to 2,040 residents in Tuba City, Navajo Nation through 143 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 35 total violations for this system , of which 1 (3%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 20 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 Coliform (TCR), recorded in 5 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 Navajo Nation, EPA tracks 170 public water systems serving 167,275 people, with 29,535 cumulative violations and 1,366 health-based violations on record. About 100% of systems in the state carry at least one violation, and state-wide the average per system is 173.7 violations. Statewide, 13 of 13 UCMR5-tested systems have reported PFAS detections (100%).

Tuba City Boarding School BIA's 35 violations sit below the Navajo Nation 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
2,040
Total Violations
35
Health-Based Violations
1
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Federal
Connections
143
School/Daycare
Yes
MCL Violations
1
Monitoring Violations
20
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 5 2004
Consumer Confidence Rule Other 4 2006
Revised Total Coliform Rule RPT 3 2024
Revised Total Coliform Rule MON 2 2023
Fluoride MR 2 2008
Dalapon MR 1 2001
Glyphosate MR 1 2001
Picloram MR 1 2001
2,4-D MR 1 2001
2,4,5-TP MR 1 2001
1,2-DIBROMO-3-CHLOROPROPANE MR 1 2001
Coliform (TCR) MCL 1 2004
Carbofuran MR 1 2001
2,3,7,8-TCDD MR 1 2001
OXAMYL MR 1 2001
CYANIDE MR 1 2001
ETHYLENE DIBROMIDE MR 1 2001

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 Tuba City Boarding School BIA.

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 NN0433001 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Navajo Nation Drinking Water Authority

Navajo Nation'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 NN 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 Revised Total Coliform Rule RPT 3 SDWIS / NN0433001 / 8000
2023 Revised Total Coliform Rule MON 2 SDWIS / NN0433001 / 8000
2008 Fluoride MR 2 SDWIS / NN0433001 / 1025
2006 Consumer Confidence Rule Other 4 SDWIS / NN0433001 / 7000
2004 Coliform (TCR) MR 5 SDWIS / NN0433001 / 3100
2004 Coliform (TCR) MCL 1 SDWIS / NN0433001 / 3100
2001 Dalapon MR 1 SDWIS / NN0433001 / 2031
2001 Glyphosate MR 1 SDWIS / NN0433001 / 2034
2001 Picloram MR 1 SDWIS / NN0433001 / 2040
2001 2,4-D MR 1 SDWIS / NN0433001 / 2105
2001 2,4,5-TP MR 1 SDWIS / NN0433001 / 2110
2001 1,2-DIBROMO-3-CHLOROPROPANE MR 1 SDWIS / NN0433001 / 2931
2001 Carbofuran MR 1 SDWIS / NN0433001 / 2046
2001 2,3,7,8-TCDD MR 1 SDWIS / NN0433001 / 2063
2001 OXAMYL MR 1 SDWIS / NN0433001 / 2036

How Tuba City Boarding School BIA Compares

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

Metric Tuba City Boarding School BIA Navajo Nation avg Federal benchmark
Total violations 35 173.7 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 1 8 Indicates a contaminant exceeded a federal MCL
PFAS detection None 100% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,040 984 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 170 regulated public water systems in Navajo Nation.

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 Tuba City Boarding School BIA water safe to drink? ▼
Tuba City Boarding School BIA (PWS ID: NN0433001) has 35 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,040 people using Groundwater sources.
How many people does Tuba City Boarding School BIA serve? ▼
Tuba City Boarding School BIA serves 2,040 people in Tuba City, Navajo Nation. It is a Federal-owned system using Groundwater water sources with 143 service connections.
What type of violations does Tuba City Boarding School BIA have? ▼
Tuba City Boarding School BIA has 35 total violations: 1 health-based violations (MCL exceedances or treatment failures), 20 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Tuba City Boarding School BIA water? ▼
No PFAS testing data is available for Tuba City Boarding School BIA under the EPA's UCMR5 monitoring program.
What water source does Tuba City Boarding School BIA use? ▼
Tuba City Boarding School BIA 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.