CITY REPORT
AZ
San Tan Valley, AZ Water Quality Report
1 ZIP code · 4 water systems · Updated 2026-03-16
Data: EPA SDWIS Last verified: 2026-03-16
1
ZIP Codes
4
Water Systems
1
ZIPs with Violations
Zone 1
Radon Risk (High)
Overview
We track water quality and home safety data for 1 ZIP code in San Tan Valley, Arizona, covering 4 community water systems serving approximately 87,435 people.
1 of 1 ZIP code (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Water Sources
San Tan Valley water systems draw from: Groundwater.
Lead & Copper
- Lead data: not yet available for San Tan Valley
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Revised Total Coliform Rule | Microbiological | 44 | 1 |
| Lead | Inorganic | 26 | 1 |
| Surface Water Treatment Rule | Treatment Technique | 18 | 1 |
| Consumer Confidence Report Rule | Reporting | 14 | 1 |
| Lead and Copper Rule | Treatment Technique | 12 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 85140 | — | 90 | 0 | EPCOR - SAN TAN |
All ZIP Codes in San Tan Valley
- 85140 — 90 violations
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.