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Community Water System · PWS NN0400397

Nazlini NTUA

Ft Defiance, Navajo Nation 86504 - drinking water served from groundwater sources to 862 people, tracked in EPA SDWIS and UCMR5.

862
People served
179
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 179 drinking-water violations at Nazlini NTUA - above the Navajo Nation per-system average.

179
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
862
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Nazlini NTUA

Nazlini NTUA is a native american-owned community water system that delivers drinking water to 862 residents in Ft Defiance, Navajo Nation through 252 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 179 total violations for this system , of which 0 (0%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 162 monitoring and reporting violations are on file. The most recent violation on record dates to 2021.

The most frequently cited contaminant at this system is Total Haloacetic Acids (HAA5), recorded in 6 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%).

Nazlini NTUA's 179 violations sit above 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
862
Total Violations
179
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Native American
Connections
252
School/Daycare
No
MCL Violations
0
Monitoring Violations
162
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Total Haloacetic Acids (HAA5) MR 6 2021
TTHM MR 6 2021
ETHYLENE DIBROMIDE MR 6 2011
Di(2-ethylhexyl) phthalate MR 4 2011
Total Polychlorinated Biphenyls (PCB) MR 4 2011
Arsenic MR 3 2011
Barium MR 3 2011
Cadmium MR 3 2011
CYANIDE MR 3 2011
Chromium MR 3 2011
Mercury MR 3 2011
Selenium MR 3 2011
Antimony, Total MR 3 2011
Beryllium, Total MR 3 2011
Thallium, Total MR 3 2011
1,2,4-Trichlorobenzene MR 3 2011
cis-1,2-Dichloroethylene MR 3 2011
1,2-DIBROMO-3-CHLOROPROPANE MR 3 2011
p-Dichlorobenzene MR 3 2011
Vinyl chloride MR 3 2011
trans-1,2-Dichloroethylene MR 3 2011
1,1,1-Trichloroethane MR 3 2011
Carbon tetrachloride MR 3 2011
1,2-Dichloropropane MR 3 2011
Toluene MR 3 2011
Styrene MR 3 2011
Coliform (TCR) MR 3 2012
Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 2013
o-Dichlorobenzene MR 3 2011
Ethylbenzene MR 3 2011

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 Nazlini NTUA.

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 NN0400397 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
2021 Total Haloacetic Acids (HAA5) MR 6 SDWIS / NN0400397 / 2456
2021 TTHM MR 6 SDWIS / NN0400397 / 2950
2016 Revised Total Coliform Rule Other 2 SDWIS / NN0400397 / 8000
2013 Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 SDWIS / NN0400397 / 0600
2012 Coliform (TCR) MR 3 SDWIS / NN0400397 / 3100
2012 Nitrite MR 1 SDWIS / NN0400397 / 1041
2012 Nitrate MR 1 SDWIS / NN0400397 / 1040
2011 ETHYLENE DIBROMIDE MR 6 SDWIS / NN0400397 / 2946
2011 Di(2-ethylhexyl) phthalate MR 4 SDWIS / NN0400397 / 2039
2011 Total Polychlorinated Biphenyls (PCB) MR 4 SDWIS / NN0400397 / 2383
2011 Arsenic MR 3 SDWIS / NN0400397 / 1005
2011 Barium MR 3 SDWIS / NN0400397 / 1010
2011 Cadmium MR 3 SDWIS / NN0400397 / 1015
2011 CYANIDE MR 3 SDWIS / NN0400397 / 1024
2011 Chromium MR 3 SDWIS / NN0400397 / 1020

How Nazlini NTUA Compares

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

Metric Nazlini NTUA Navajo Nation avg Federal benchmark
Total violations 179 173.7 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 0 8 Indicates a contaminant exceeded a federal MCL
PFAS detection None 100% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 862 984 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 Nazlini NTUA water safe to drink? ▼
Nazlini NTUA (PWS ID: NN0400397) has 179 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 862 people using Groundwater sources.
How many people does Nazlini NTUA serve? ▼
Nazlini NTUA serves 862 people in Ft Defiance, Navajo Nation. It is a Native American-owned system using Groundwater water sources with 252 service connections.
What type of violations does Nazlini NTUA have? ▼
Nazlini NTUA has 179 total violations: 0 health-based violations (MCL exceedances or treatment failures), 162 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Nazlini NTUA water? ▼
No PFAS testing data is available for Nazlini NTUA under the EPA's UCMR5 monitoring program.
What water source does Nazlini NTUA use? ▼
Nazlini NTUA 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.