Public water system · AZ0414005
ActiveSan Luis City of
At a glance
City of San Luis (PWSID AZ0414005) is an active community water system in Yuma County, Arizona. It reports serving 39,705 people through 6,100 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, 3 are health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
39,705
Service connections
6,100
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of San Luis compare with other water systems in Yuma County?
By EPA's size categories, City of San Luis is a large system (10,001 to 100,000 people). Yuma County has 50 active public water systems, and City of San Luis is the 2nd-largest of them by population served. Its population served is about 9 times the county average of 4,392 people per system, and accounts for 18% of the 219,583 people reported by systems filed under the county. 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 City of San Luis is about 5.9 times 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 City of San Luis?
EPA lists City of San Luis as owned by a local 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. 9 of the 50 active systems in Yuma County (18%) are also owned by a local government.
Does City of San Luis have drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in October 2024. The violations listed here began between September 2017 and October 2024. By type: 4 monitoring and reporting, 3 required treatment not met, 3 reporting and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Revised Total Coliform Rule (5 of them). EPA lists 11 as resolved and 1 as unaddressed. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2024-06-06 | Required treatment not metFailure To Address Deficiency · code 45 | Groundwater Rulecode 0700 | Yes | Resolved |
| 2024-02-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-09-28 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2021-09-15 | Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A | Revised Total Coliform Rulecode 8000 | Yes | Unaddressed |
| 2021-09-08 | Monitoring and reportingFailure Submit IDSE/Subpart V Plan Rpt · code 35 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2021-09-01 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2021-08-05 | Required treatment not metFailure To Address Deficiency · code 45 | Groundwater Rulecode 0700 | Yes | Resolved |
| 2021-08-01 | Public notice, recordkeeping or otherSample Siting Plan Errors (RTCR) · code 5A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2019-05-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-09-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | 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.
City of San Luis: frequently asked questions
Who runs City of San Luis?
City of San Luis (PWSID AZ0414005) is a community water system owned by a local government. It is regulated by the AZ state drinking water program.
How many people does City of San Luis serve?
City of San Luis reports serving 39,705 people through 6,100 service connections in Yuma County, Arizona.
Where does City of San Luis 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 City of San Luis 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 October 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 City of San Luis' 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 October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the AZ state drinking water program.
Where can I find City of San Luis' water quality report?
As a community water system, City of San Luis 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 Yuma County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Yuma | Yuma | 103,264 | Community | Surface water |
| Foothills Water and Sewer LLC | Yuma | 32,425 | Community | Surface water |
| Somerton City of | Yuma | 14,197 | Community | Groundwater |
| Usmc Yuma Main System | Yuma | 8,353 | Community | Surface water |
| Aspc Yuma | Yuma | 4,197 | Community | Groundwater |
| Wellton Town of | Yuma | 3,000 | 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 Luis City of, PWSID AZ0414005, Arizona”, https://aquacensus.com/water-systems/arizona/san-luis-city-of-az0414005 (data as of October 1, 2026).