F0/100

EPCOR - SAN TAN — Water Quality Report 2026

Serving 87,435 people · Arizona

Water Source
Groundwater
County
System ID
AZ0411128
Violations
267

Contaminant Test Results

EPA Violation History

31

Violations (last 5yr)

0

Unresolved

0

Health-Related

TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: December 1, 2024 – December 31, 2024Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: September 1, 2024 – September 30, 2024Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2024 – April 30, 2024Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2024 – December 31, 2024Rule: Revised Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2022 – June 30, 2022Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2022 – June 30, 2022Enforcement: Resolving — corrective action underway
TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2022 – June 30, 2022Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: April 1, 2022 – June 30, 2022Enforcement: Resolving — corrective action underway

Understanding violation severity

Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.

Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly

Frequently Asked Questions About EPCOR - SAN TAN

Is EPCOR - SAN TAN water safe to drink?

EPCOR - SAN TAN water receives a grade of F (0/100), which is considered failing. 0 contaminant(s) exceed EPA legal limits and 267 violation(s) are on record. Customers may want to consider using a water filter.

What contaminants has EPCOR - SAN TAN detected?

66 contaminants were tested in EPCOR - SAN TAN's water. No contaminants exceed EPA legal limits or health goals, indicating good water quality management.

Does EPCOR - SAN TAN have any EPA violations?

Yes, EPCOR - SAN TAN has 267 EPA violation(s) on record, with the most recent in 2024. Violation types include MR, MCL, Other. 7 are health-based violations.

How many people does EPCOR - SAN TAN serve?

EPCOR - SAN TAN serves approximately 87,435 people, Arizona. The system provides water to 1 community: Johnson Ranch.

What type of water does EPCOR - SAN TAN provide?

EPCOR - SAN TAN sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is AZ0411128.

How does EPCOR - SAN TAN compare to other utilities in Arizona?

EPCOR - SAN TAN scores 0/100 with a grade of F (failing). This score suggests significant water quality concerns relative to other utilities. Visit our Arizona state page for a full comparison of water systems.

Cities Served