Water Quality in 85140 — San Tan Valley, AZ
EPA data for EPCOR - SAN TAN
Data source: U.S. Environmental Protection Agency (EPA) SDWIS Last verified: March 16, 2026
Your Water System
ZIP code 85140 in San Tan Valley, Arizona is served by EPCOR - SAN TAN (EPA ID: AZ0411128). This system provides water to approximately 87,435 people from groundwater sources.
There are 4 community water systems serving this area.
Lead & Copper in Your Water
No Lead & Copper Rule sampling data available for systems serving this ZIP code.
Violation Summary
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| July 1, 2025 | Surface Water Treatment Rule | Monitoring | Unresolved |
| July 1, 2025 | Lead | Monitoring | Unresolved |
| March 1, 2025 | Revised Total Coliform Rule | Monitoring | Unresolved |
| February 1, 2025 | Revised Total Coliform Rule | Monitoring | Unresolved |
| January 1, 2025 | Revised Total Coliform Rule | Monitoring | Unresolved |
| December 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| October 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| September 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| September 1, 2024 | Revised Total Coliform Rule | Monitoring | Unresolved |
| September 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Unresolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Unresolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Resolved |
| January 1, 2024 | Lead | Monitoring | Resolved |
| January 1, 2024 | Lead | Monitoring | Resolved |
| January 1, 2024 | PFOA | Monitoring | Resolved |
| January 1, 2024 | PFNA | Monitoring | Resolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for water systems serving this ZIP code:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Revised Total Coliform Rule | Microbiological | 22 | No |
| Lead | Inorganic | 13 | No |
| Surface Water Treatment Rule | Treatment Technique | 9 | No |
| Consumer Confidence Report Rule | Reporting | 7 | No |
| Lead and Copper Rule | Treatment Technique | 6 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 5 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 5 | No |
| Stage 1 DBP Rule | Treatment Technique | 3 | No |
| PFOA | PFAS | 1 | No |
| PFNA | PFAS | 1 | No |
| Monochloroacetic Acid | Disinfection Byproducts | 1 | No |
| Dichloroacetic Acid | Disinfection Byproducts | 1 | No |
| Bromodichloromethane | Disinfection Byproducts | 1 | No |
| Dibromochloromethane | Disinfection Byproducts | 1 | No |
| Chlorodibromomethane | Disinfection Byproducts | 1 | No |
Need help with your water quality?
Call to get connected with a local professional in your area.
Call (855) 384-4856This is a free service. You will be connected with an independent service provider.
Water Systems Serving This Area
| System Name | EPA ID | Population | Source |
|---|---|---|---|
| EPCOR - SAN TAN | AZ0411128 | 87,435 | Groundwater |
| EPCOR - SAN TAN ANTHEM | AZ0411136 | 10,362 | Groundwater |
| SUN VALLEY FARMS UNIT VI | AZ0411111 | 600 | Groundwater |
| SKYLINE RESORT RV PARK | AZ0411556 | 375 | Groundwater |
What You Can Do
- Review your annual Consumer Confidence Report (CCR) — Your utility publishes this each July
- Test your home’s water — Especially if you have older plumbing (pre-1986) that may contain lead
- Stay informed — Bookmark this page to check for updates on your water quality
Need help with water testing or filtration?
Call to get connected with a local professional in your area.
Call (855) 384-4856This is a free service. You will be connected with an independent service provider.
Other Water Quality Reports in Arizona
- 85001 (Phoenix) — 248 violations
- 85117 (Apache Junction) — 263 violations
- 85122 (Casa Grande) — 52 violations
- 85123 (Arizona City) — 94 violations
- 85127 (Chandler Heights) — 6 violations
- 85128 (Coolidge) — 101 violations
- 85131 (Eloy) — 139 violations
- 85132 (Florence) — 109 violations
- 85135 (Hayden) — 91 violations
- 85137 (Kearny) — 82 violations
- 85138 (Maricopa) — 428 violations
- 85141 (Picacho) — 88 violations
- 85142 (Queen Creek) — 70 violations
- 85145 (Red Rock) — 43 violations
- 85172 (Stanfield) — 92 violations
- 85173 (Superior) — 11 violations
- 85201 (Mesa) — 38 violations
- 85224 (Chandler) — 259 violations
- 85233 (Gilbert) — 364 violations
- 85250 (Scottsdale) — 34 violations
Nearby Water Quality Reports
- 85142 (Queen Creek) — 7 mi — 70 violations
- 85127 (Chandler Heights) — 10 mi — 6 violations
- 85117 (Apache Junction) — 15 mi — 263 violations
- 85128 (Coolidge) — 16 mi — 101 violations
- 85132 (Florence) — 17 mi — 109 violations
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for EPCOR - SAN TAN (AZ0411128) on EPA.gov.
Frequently Asked Questions
Is the tap water in 85140 safe to drink?
Based on EPA records, the water system serving ZIP code 85140 has only monitoring/reporting violations, which are procedural in nature. However, individual home conditions (old pipes, well water) can affect quality.
Where does 85140’s water come from?
The primary water source for this area is groundwater. EPCOR - SAN TAN serves approximately 87,435 people.
How can I get my water tested?
Contact your local water utility for a free water quality report, or hire a certified lab for independent home water testing. The EPA recommends testing annually if you use a private well.
Does 85140 have lead in the water?
No Lead and Copper Rule sampling data is currently available in EPA records for water systems serving ZIP code 85140. If you are concerned about lead, contact your water utility or have your tap water independently tested.
What is the radon risk in 85140?
Radon zone data is not available for ZIP code 85140. The EPA recommends testing all homes for radon regardless of location, as radon levels can vary significantly even within the same neighborhood.