Public water system · 090400701
ActiveSan Carlos High School
At a glance
San Carlos High School (PWSID 090400701) is an active non-transient non-community water system in Arizona. It reports serving 626 people through 9 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in November 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
626
Service connections
9
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does San Carlos High School compare with other water systems in Arizona?
By EPA's size categories, San Carlos High School 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 non-transient non-community water system reports serving 430 people, so San Carlos High School is about 46% above that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Arizona has 232 active non-transient non-community water systems, 13% 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 San Carlos High School?
EPA lists San Carlos High School as owned by a local government. The EPA Region 09 is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act.
Does San Carlos High School have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in November 2024. The violations listed here began between January 2022 and November 2024. By type: 8 monitoring and reporting, 3 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Chlorine (5 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 |
|---|---|---|---|---|
| 2024-11-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2024-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2023-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2023-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2022-12-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2022-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | 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.
San Carlos High School: frequently asked questions
Who runs San Carlos High School?
San Carlos High School (PWSID 090400701) is a non-transient non-community water system owned by a local government. It is regulated by the EPA Region 09.
How many people does San Carlos High School serve?
San Carlos High School reports serving 626 people through 9 service connections in Arizona.
Where does San Carlos High School 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 San Carlos High School have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in November 2024. 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 San Carlos High School'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, none is health-based, and the most recent began in November 2024. For current results, consult EPA ECHO, or the EPA Region 09.
Where can I find San Carlos High School's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. San Carlos High School is a non-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 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, “San Carlos High School, PWSID 090400701, Arizona”, https://aquacensus.com/water-systems/arizona/san-carlos-high-school-090400701 (data as of October 1, 2026).