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Sweetwater NTUA

PWS ID: NN0400399 · Ft Defiance, Navajo Nation 86504

Sweetwater NTUA serves 2,014 people in Ft Defiance, Navajo Nation using Surface Water water sources. It has 156 recorded EPA violations, including 44 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: Sweetwater NTUA

Sweetwater NTUA is a native american-owned community water system that delivers drinking water to 2,014 residents in Ft Defiance, Navajo Nation through 589 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 156 total violations for this system , of which 44 (28%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 68 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Arsenic, recorded in 37 violations (MCL, 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 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. Sweetwater NTUA's 156 violations sit below the Navajo Nation average. Statewide, 13 of 13 UCMR5-tested systems have reported PFAS detections (100%). 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
2,014
Total Violations
156
Health-Based Violations
44
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Native American
Connections
589
School/Daycare
No
MCL Violations
44
Monitoring Violations
68
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Arsenic MCL 37 2025
Public Notice Other 23 2024
Arsenic MR 8 2022
Coliform (TCR) MCL 4 2015
Coliform (TCR) MR 4 2012
Total Polychlorinated Biphenyls (PCB) MR 3 2008
TTHM MCL 3 2020
1,2-DIBROMO-3-CHLOROPROPANE MR 3 2008
Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 2013
ETHYLENE DIBROMIDE MR 3 2008
1,2,4-Trichlorobenzene MR 2 2008
Xylenes, Total MR 2 2008
DICHLOROMETHANE MR 2 2008
o-Dichlorobenzene MR 2 2008
p-Dichlorobenzene MR 2 2008
Vinyl chloride MR 2 2008
1,1-Dichloroethylene MR 2 2008
trans-1,2-Dichloroethylene MR 2 2008
1,2-Dichloroethane MR 2 2008
1,1,1-Trichloroethane MR 2 2008
Carbon tetrachloride MR 2 2008
1,2-Dichloropropane MR 2 2008
Trichloroethylene MR 2 2008
1,1,2-Trichloroethane MR 2 2008
CHLOROBENZENE MR 2 2008
Benzene MR 2 2008
Toluene MR 2 2008
Ethylbenzene MR 2 2008
Styrene MR 2 2008
Tetrachloroethylene MR 2 2008

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 Sweetwater 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 NN0400399 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
2025 Arsenic MCL 37 SDWIS / NN0400399 / 1005
2024 Public Notice Other 23 SDWIS / NN0400399 / 7500
2022 Arsenic MR 8 SDWIS / NN0400399 / 1005
2020 TTHM MCL 3 SDWIS / NN0400399 / 2950
2016 Revised Total Coliform Rule Other 2 SDWIS / NN0400399 / 8000
2015 Coliform (TCR) MCL 4 SDWIS / NN0400399 / 3100
2013 Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 SDWIS / NN0400399 / 0600
2012 Coliform (TCR) MR 4 SDWIS / NN0400399 / 3100
2010 Nitrate MR 1 SDWIS / NN0400399 / 1040
2010 Nitrite MR 1 SDWIS / NN0400399 / 1041
2008 Total Polychlorinated Biphenyls (PCB) MR 3 SDWIS / NN0400399 / 2383
2008 1,2-DIBROMO-3-CHLOROPROPANE MR 3 SDWIS / NN0400399 / 2931
2008 ETHYLENE DIBROMIDE MR 3 SDWIS / NN0400399 / 2946
2008 1,2,4-Trichlorobenzene MR 2 SDWIS / NN0400399 / 2378
2008 Xylenes, Total MR 2 SDWIS / NN0400399 / 2955

How Sweetwater NTUA Compares

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

Metric Sweetwater NTUA Navajo Nation avg Federal benchmark
Total violations 156 173.7 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 44 8 Indicates a contaminant exceeded a federal MCL
PFAS detection None 100% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,014 984 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
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Sweetwater NTUA water safe to drink? ▼
Sweetwater NTUA (PWS ID: NN0400399) has 156 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,014 people using Surface Water sources.
How many people does Sweetwater NTUA serve? ▼
Sweetwater NTUA serves 2,014 people in Ft Defiance, Navajo Nation. It is a Native American-owned system using Surface Water water sources with 589 service connections.
What type of violations does Sweetwater NTUA have? ▼
Sweetwater NTUA has 156 total violations: 44 health-based violations (MCL exceedances or treatment failures), 68 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Sweetwater NTUA water? ▼
No PFAS testing data is available for Sweetwater NTUA under the EPA's UCMR5 monitoring program.
What water source does Sweetwater NTUA use? ▼
Sweetwater NTUA 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.

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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.

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Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by PlainWater Editorial