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Community Water System · PWS NN4903018

Montezuma Creek NTUA

Operator location Ft Defiance, Navajo Nation - 32% of 130 violations are health-based (upper-third health share (> 23%)); groundwater source; 424 served per SDWIS.

424
People served (this PWS) Smaller third of systems
130
EPA violations (this PWS) Upper third of systems
42
Health-based (this PWS) Upper third by health-based share
Untested
UCMR5 (this PWS) No UCMR5 result
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Montezuma Creek NTUA standing, high SDWIS violation third

32% of 130 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 32% is upper-third health share (> 23%).

The verdict

Montezuma Creek NTUA sits in the upper third of the sitemap cohort by violation count (130), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (424; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 32% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.

130
Total EPA violations on record
32%
Health-based (MCL / treatment failure)
424
People served by this PWS (SDWIS)
N/A
PFAS compounds detected (UCMR5)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

F
Water Safety Score
7/100
Montezuma Creek NTUA

Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.

Health-based violations F
42
EPA SDWIS health-based violations on record (MCL, MRDL, treatment technique)
Monitoring & reporting violations F
88
Non-health SDWIS violations (monitoring, reporting, and other compliance)
PFAS contamination N/A
Not UCMR5-tested
Highest PFAS compound level detected in UCMR5 testing

System Details

System Type
Community
Owner Type
Native American
Connections
124
School/Daycare
No
MCL Violations
42
Monitoring Violations
71
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Arsenic MCL 39 2015
Arsenic MR 9 2022
Coliform (TCR) MR 7 2015
Fluoride MR 6 2011
Public Notice Other 4 2015
Barium MR 3 2008
Cadmium MR 3 2008
Chromium MR 3 2008
CYANIDE MR 3 2008
Mercury MR 3 2008
Diquat MR 3 2008
Endothall MR 3 2008
2,3,7,8-TCDD MR 3 2008
ETHYLENE DIBROMIDE MR 3 2008
Coliform (TCR) MCL 3 2011
Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 2013
Glyphosate MR 3 2008
Selenium MR 3 2008
Beryllium, Total MR 3 2008
Total Polychlorinated Biphenyls (PCB) MR 3 2008
Thallium, Total MR 3 2008
Dalapon MR 3 2008
Revised Total Coliform Rule Other 2 2016
Nitrite MR 1 2010

Violation Count vs. the National Corpus

Montezuma Creek NTUA has 130 recorded EPA violations, 78% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 21% carry more. 32% of this system's own violations are health-based (42 of 130), and it ranks unranked by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

130 Higher than most more violations than 78% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

How many violations vs. how serious, among peer systems

Montezuma Creek NTUA plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.

Violation volume vs. health-based share

30 public water systems (500+ people served), EPA SDWIS current release. 2×2 strategic matrix plotting 30 entities by Total violations (X) and Health-based share (Y), with a crosshair dividing the plot into four quadrants. Frequent and seriousRare but seriousFrequent, mostly paperworkClean record 0200400600 0%20%40%60%80%100% Total violations Health-based share Violation volume vs. health-based share Miccosukee Service Plaza-0, 0%Brazoria - Fort Bend Counties MUD 3-0, 0%Tanglewilde Thompson Place 600-2, 0%Center Water Co-5, 0%Montgomery Co RWD 12-7, 29%Spring Mills Elem School/Hvs-9, 0%Irvin Water District #6-11, 27%Great Bend Industrial Park-14, 0%Nooksack Valley Water Association-16, 31%Glen Park Village-19, 0%Camp Is-Sho-Da-22, 0%Kipling Oaks 1-25, 16%McLouth, City Of-29, 17%Hamilton-33, 0%Pine Valley Plantation-37, 24%Lake Gibson Estates-42, 2%Ticonderoga WD-47, 26%Town of Welaka-54, 0%Township of Blairstown Dpw-61, 0%McIntosh Water & Fire Pro Authority-71, 0%Sunset Ridge Water District-82, 15%South Deerfield Water Supply District-96, 16%Clarkdale Municipal Water System-114, 0%Orange Water Dept-136, 14%Mount Pleasant Water Sys #1-167, 11%Benson Culinary Improvement District-212, 1%Eureka Water Association-273, 0%City of Ballinger-372, 85%Conemaugh Twp Muni Auth-567, 1%Montezuma Creek NTUA-130, 32%
30 public water systems (500+ people served), EPA SDWIS current release.

Health-based violations on Montezuma Creek NTUA

42 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for NN4903018.

Sources: EPA SDWIS

Nationwide peers

130 violations · 424 served: nearest cross-state SDWIS matches.

What to do with Montezuma Creek NTUA

Use this system's EPA-reported record as a starting filter, not a final verdict.

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.