Public water system · AZ0407110
ActiveAdot Sentinel Rest Area C21
At a glance
Adot Sentinel Rest Area C21 (PWSID AZ0407110) is an active transient non-community water system in Maricopa County, Arizona. It reports serving 200 people through 3 service connections. Its primary water source is groundwater, and EPA lists it as owned by a state government. Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2021.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
200
Service connections
3
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Adot Sentinel Rest Area C21 compare with other water systems in Maricopa County?
By EPA's size categories, Adot Sentinel Rest Area C21 is a very small system (500 people or fewer). Maricopa County has 217 active public water systems. Its population served is well below the county average of 20,368 people per system, and accounts for less than 0.1% of the 4,419,761 people reported by systems filed under the county. Across Arizona, the 1,769 active systems average 4,369 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Adot Sentinel Rest Area C21 is about 39% above that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Arizona has 601 active transient non-community water systems, 34% 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 Adot Sentinel Rest Area C21?
EPA lists Adot Sentinel Rest Area C21 as owned by a state government. The AZ state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 5 of the 217 active systems in Maricopa County (2.3%) are also owned by a state government.
Does Adot Sentinel Rest Area C21 have drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2021. The violations listed here began between February 2005 and March 2021. By type: 4 reporting, 4 monitoring and reporting, 3 contaminant level above the legal limit and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 12 as resolved. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2021-03-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-02-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-10-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-02-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2015-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2014-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2012-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2005-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-07-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2005-02-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
The 12 most recent 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.
Adot Sentinel Rest Area C21: frequently asked questions
Who runs Adot Sentinel Rest Area C21?
Adot Sentinel Rest Area C21 (PWSID AZ0407110) is a transient non-community water system owned by a state government. It is regulated by the AZ state drinking water program.
How many people does Adot Sentinel Rest Area C21 serve?
Adot Sentinel Rest Area C21 reports serving 200 people through 3 service connections in Maricopa County, Arizona.
Where does Adot Sentinel Rest Area C21 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 Adot Sentinel Rest Area C21 have any drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2021. 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 Adot Sentinel Rest Area C21'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. Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in March 2021. For current results, consult EPA ECHO, or the AZ state drinking water program.
Where can I find Adot Sentinel Rest Area C21's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Adot Sentinel Rest Area C21 is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Maricopa County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Phoenix City of | Maricopa | 1,695,000 | Community | Surface water |
| 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 |
| Glendale City of | Maricopa | 234,766 | 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, “Adot Sentinel Rest Area C21, PWSID AZ0407110, Arizona”, https://aquacensus.com/water-systems/arizona/adot-sentinel-rest-area-c21-az0407110 (data as of October 1, 2026).