Public water system · AZ0412020
ActiveCasas Arroyo Association Inc.
At a glance
Casas Arroyo Association Inc. (PWSID AZ0412020) is an active community water system in Santa Cruz County, Arizona. It reports serving 27 people through 27 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in May 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
27
Service connections
27
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Casas Arroyo Association Inc. compare with other water systems in Santa Cruz County?
By EPA's size categories, Casas Arroyo Association Inc. is a very small system (500 people or fewer). Santa Cruz County has 37 active public water systems. Its population served is well below the county average of 1,350 people per system, and accounts for less than 0.1% of the 49,946 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 Casas Arroyo Association Inc. 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 Casas Arroyo Association Inc.?
EPA lists Casas Arroyo Association Inc. as privately owned. 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. 12 of the 37 active systems in Santa Cruz County (32%) are also privately owned.
Does Casas Arroyo Association Inc. have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in May 2025. The violations listed here began between April 2019 and May 2025. By type: 4 public notice, recordkeeping or other, 3 reporting, 3 monitoring and reporting and 2 required treatment not met. The contaminant or rule involved most often is Public Notice (2 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 |
|---|---|---|---|---|
| 2025-05-12 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2025-03-23 | Required treatment not metFailure To Address Deficiency · code 45 | Groundwater Rulecode 0700 | Yes | Resolved |
| 2024-12-20 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Resolved |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Resolved |
| 2024-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2022-12-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-10-02 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2021-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2020-06-18 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2019-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2019-04-01 | 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.
Casas Arroyo Association Inc.: frequently asked questions
Who runs Casas Arroyo Association Inc.?
Casas Arroyo Association Inc. (PWSID AZ0412020) is a community water system privately owned. It is regulated by the AZ state drinking water program.
How many people does Casas Arroyo Association Inc. serve?
Casas Arroyo Association Inc. reports serving 27 people through 27 service connections in Santa Cruz County, Arizona.
Where does Casas Arroyo Association Inc. 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 Casas Arroyo Association Inc. have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in May 2025. 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 Casas Arroyo Association Inc.'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, 2 are health-based, and the most recent began in May 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the AZ state drinking water program.
Where can I find Casas Arroyo Association Inc.'s water quality report?
As a community water system, Casas Arroyo Association Inc. 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 Santa Cruz County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Nogales City of | Santa Cruz | 22,000 | Community | Groundwater |
| Liberty Water Rio Rico | Santa Cruz | 17,960 | Community | Groundwater |
| Valle Verde Water Company - East | Santa Cruz | 2,331 | Community | Groundwater |
| Epcor - Tubac | Santa Cruz | 2,076 | Community | Groundwater |
| Baca Float Water Company | Santa Cruz | 1,090 | Community | Groundwater |
| Patagonia Water Department | Santa Cruz | 819 | Community | Groundwater |
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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, “Casas Arroyo Association Inc., PWSID AZ0412020, Arizona”, https://aquacensus.com/water-systems/arizona/casas-arroyo-association-inc-az0412020 (data as of October 1, 2026).