Public water system · NN0400283
ActiveInscription House-Navajo Mountain NTUA
At a glance
Inscription House-Navajo Mountain NTUA (PWSID NN0400283) is an active community water system in Arizona. It reports serving 1,368 people through 400 service connections. Its primary water source is groundwater, and EPA lists it as Native American-owned. EPA's records list 9 violations for this system; 1 is health-based, and the most recent began in April 2016.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,368
Service connections
400
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Inscription House-Navajo Mountain NTUA compare with other water systems in Arizona?
By EPA's size categories, Inscription House-Navajo Mountain NTUA is a small system (501 to 3,300 people). Across Arizona, the 1,769 active systems average 4,369 people each. Nationally, the average active community water system reports serving 6,703 people, so Inscription House-Navajo Mountain NTUA is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Arizona has 936 active community water systems, 53% of the state's 1,769 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,612 Arizona systems (91%) list groundwater as their primary source.
Who owns and regulates Inscription House-Navajo Mountain NTUA?
EPA lists Inscription House-Navajo Mountain NTUA as Native American-owned. The NN state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act.
Does Inscription House-Navajo Mountain NTUA have drinking water violations?
EPA's records list 9 violations for this system; 1 is health-based, and the most recent began in April 2016. The violations listed here began between July 1996 and April 2016. By type: 7 monitoring and reporting, 1 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 6 as resolved, 2 as unaddressed and 1 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2016-04-01 | Public notice, recordkeeping or otherSample Siting Plan Errors (RTCR) · code 5A | Revised Total Coliform Rulecode 8000 | No | Unaddressed |
| 2013-10-01 | Monitoring and reportingFailure Submit IDSE/Subpart V Plan Rpt · code 35 | Stage 2 Disinfectants and Disinfection Byproducts Rulecode 0600 | No | Unaddressed |
| 2013-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2012-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2012-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitritecode 1041 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1996-07-31 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1996-07-31 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Archived |
All 9 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Inscription House-Navajo Mountain NTUA: frequently asked questions
Who runs Inscription House-Navajo Mountain NTUA?
Inscription House-Navajo Mountain NTUA (PWSID NN0400283) is a community water system Native American-owned. It is regulated by the NN state drinking water program.
How many people does Inscription House-Navajo Mountain NTUA serve?
Inscription House-Navajo Mountain NTUA reports serving 1,368 people through 400 service connections in Arizona.
Where does Inscription House-Navajo Mountain NTUA get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Inscription House-Navajo Mountain NTUA have any drinking water violations?
EPA's records list 9 violations for this system; 1 is health-based, and the most recent began in April 2016. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Inscription House-Navajo Mountain NTUA's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 9 violations for this system; 1 is health-based, and the most recent began in April 2016. For current results, consult the system's annual water quality report, EPA ECHO, or the NN state drinking water program.
Where can I find Inscription House-Navajo Mountain NTUA's water quality report?
As a community water system, Inscription House-Navajo Mountain NTUA must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Arizona
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Phoenix City of | Maricopa | 1,695,000 | Community | Surface water |
| Tucson City of | Pima | 732,906 | Community | Groundwater |
| Mesa City of | Maricopa | 466,000 | Community | Surface water |
| Gilbert, Town of | Maricopa | 247,600 | Community | Surface water |
| Chandler City of | Maricopa | 247,328 | Community | Surface water |
| Scottsdale City of | Maricopa | 241,361 | Community | Surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Inscription House-Navajo Mountain NTUA, PWSID NN0400283, Arizona”, https://aquacensus.com/water-systems/arizona/inscription-house-navajo-mountain-ntua-nn0400283 (data as of October 1, 2026).