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Community Water System · PWS AZ0407532

Epcor - Tierra del Rio

El Mirage, Arizona 85335 - drinking water served from groundwater sources to 4,868 people, tracked in EPA SDWIS and UCMR5.

4,868
People served
3
EPA violations
0
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 3 drinking-water violations at Epcor - Tierra del Rio - below the Arizona per-system average.

3
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
4,868
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Epcor - Tierra del Rio

Epcor - Tierra del Rio is a local-owned community water system that delivers drinking water to 4,868 residents in El Mirage, Arizona (Maricopa County) through 1,770 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 3 total violations for this system , of which 0 (0%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. The most recent violation on record dates to 2012.

The most frequently cited contaminant at this system is Consumer Confidence Rule, recorded in 3 violations (Other). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

Across Arizona, EPA tracks 1,493 public water systems serving 7,322,166 people, with 228,944 cumulative violations and 15,663 health-based violations on record. About 98% of systems in the state carry at least one violation, and state-wide the average per system is 153.3 violations. Statewide, 145 of 152 UCMR5-tested systems have reported PFAS detections (95.4%).

Epcor - Tierra del Rio's 3 violations sit below the Arizona average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
4,868
Total Violations
3
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,770
County
Maricopa
School/Daycare
No
MCL Violations
0
Monitoring Violations
0
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Consumer Confidence Rule Other 3 2012

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 58 samples detected PFAS.

Contaminant Date Result MRL Status
PFDA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFBS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 8/15/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 8/15/2023 <2.00 ppt 2.00 ppt Not Detected
PFEESA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 8/15/2023 <20.00 ppt 20.00 ppt Not Detected
PFHpS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFMBA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
8:2 FTS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
ADONA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
NMeFOSAA 6/19/2023 <6.00 ppt 6.00 ppt Not Detected
PFTA 6/19/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 6/19/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 6/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFTA 2/14/2024 <8.00 ppt 8.00 ppt Not Detected
NMeFOSAA 2/14/2024 <6.00 ppt 6.00 ppt Not Detected
PFTrDA 2/14/2024 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 2/14/2024 <5.00 ppt 5.00 ppt Not Detected
PFMPA 12/13/2023 <4.00 ppt 4.00 ppt Not Detected
11Cl-PF3OUdS 12/13/2023 <5.00 ppt 5.00 ppt Not Detected
PFEESA 12/13/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 12/13/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 12/13/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 12/13/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 12/13/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 12/13/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 12/13/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 12/13/2023 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 12/13/2023 <5.00 ppt 5.00 ppt Not Detected
ADONA 12/13/2023 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 12/13/2023 <2.00 ppt 2.00 ppt Not Detected
PFPeA 12/13/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 12/13/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 12/13/2023 <2.00 ppt 2.00 ppt Not Detected
PFBS 12/13/2023 <3.00 ppt 3.00 ppt Not Detected

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Epcor - Tierra del Rio.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID AZ0407532 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Arizona Drinking Water Authority

Arizona DEQ, Drinking Water Program is the primacy agency that licenses and inspects Epcor - Tierra del Rio under EPA-delegated authority.

Open AZ regulator portal

Source: Arizona DEQ, Drinking Water Program

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2012 Consumer Confidence Rule Other 3 SDWIS / AZ0407532 / 7000

How Epcor - Tierra del Rio Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Epcor - Tierra del Rio Arizona avg Federal benchmark
Total violations 3 153.3 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 0 10.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 95.4% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 4,868 4,904 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 1,493 regulated public water systems in Arizona.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Epcor - Tierra del Rio water safe to drink? ▼
Epcor - Tierra del Rio (PWS ID: AZ0407532) has 3 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 4,868 people using Groundwater sources.
How many people does Epcor - Tierra del Rio serve? ▼
Epcor - Tierra del Rio serves 4,868 people in El Mirage, Arizona. It is a Local-owned system using Groundwater water sources with 1,770 service connections.
What type of violations does Epcor - Tierra del Rio have? ▼
Epcor - Tierra del Rio has 3 total violations: 0 health-based violations (MCL exceedances or treatment failures), 0 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Epcor - Tierra del Rio water? ▼
No. Epcor - Tierra del Rio was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Epcor - Tierra del Rio use? ▼
Epcor - Tierra del Rio uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.