Public water system · AZ0407500
ActiveSurprise City of - Mountain Vista
At a glance
Surprise City of - Mountain Vista (PWSID AZ0407500) is an active community water system in Maricopa County, Arizona. It reports serving 40,007 people through 15,167 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 January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
40,007
Service connections
15,167
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Surprise City of - Mountain Vista compare with other water systems in Maricopa County?
By EPA's size categories, Surprise City of - Mountain Vista is a large system (10,001 to 100,000 people). Maricopa County has 217 active public water systems. Its population served is about twice the county average of 20,368 people per system, and accounts for 0.9% 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 community water system reports serving 6,703 people, so Surprise City of - Mountain Vista is about 6 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 Surprise City of - Mountain Vista?
EPA lists Surprise City of - Mountain Vista 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. 40 of the 217 active systems in Maricopa County (18%) are also owned by a local government.
Does Surprise City of - Mountain Vista have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026. The violations listed here began between October 2019 and January 2026. By type: 12 monitoring and reporting. The contaminant or rule involved most often is Dichloromethane (4 of them). EPA lists 12 as archived. 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 |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Archived |
| 2026-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Trichloroethylenecode 2984 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Styrenecode 2996 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloropropanecode 2983 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | cis-1,2-Dichloroethylenecode 2380 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Ethylbenzenecode 2992 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Ethylbenzenecode 2992 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Archived |
| 2019-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | trans-1,2-Dichloroethylenecode 2979 | No | Archived |
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.
Surprise City of - Mountain Vista: frequently asked questions
Who runs Surprise City of - Mountain Vista?
Surprise City of - Mountain Vista (PWSID AZ0407500) is a community water system owned by a local government. It is regulated by the AZ state drinking water program.
How many people does Surprise City of - Mountain Vista serve?
Surprise City of - Mountain Vista reports serving 40,007 people through 15,167 service connections in Maricopa County, Arizona.
Where does Surprise City of - Mountain Vista 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 Surprise City of - Mountain Vista 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 January 2026. 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 Surprise City of - Mountain Vista'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 January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the AZ state drinking water program.
Where can I find Surprise City of - Mountain Vista's water quality report?
As a community water system, Surprise City of - Mountain Vista 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 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, “Surprise City of - Mountain Vista, PWSID AZ0407500, Arizona”, https://aquacensus.com/water-systems/arizona/surprise-city-of-mountain-vista-az0407500 (data as of October 1, 2026).