San Tan Valley, AZ: 62 Violations — 69/100 (2026)
2 ZIP codes · 5 water systems · Updated 2026-06-03
Across water systems in San Tan Valley, safety results are uneven — a portion carry active or recent violations, while others meet federal standards without incident, placing the city in the middle tier for AZ.
How San Tan Valley Compares
Data: EPA SDWIS Last verified: 2026-06-03
San Tan Valley Water: The Quick Version
- Your city's water systems recorded 62 violations in the past 5 years.
- Average lead level: 0.0018 mg/L.
- Homes built before 1986: 4% — older plumbing may contain lead solder.
- Estimated remediation: $2,200 per household.
- CDC health risk index: 13.46 — above typical levels.
Water Systems Serving San Tan Valley
At present, 3 utilities serve the bulk of San Tan Valley, AZ's residential water connections out of 5 systems active in the area, spread across independent providers with separate infrastructure and compliance obligations.
Overview
We track water quality and home safety data for 2 ZIP codes in San Tan Valley, Arizona (population ~92,595), covering 5 community water systems serving approximately 194,274 people region-wide.
2 of 2 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for San Tan Valley: C (69/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
San Tan Valley water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0018 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 2 ZIP codes
- Zone 3 (Low): 0 ZIP codes
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 | 33 | 2 |
| Surface Water Treatment Rule | Treatment Technique | 15 | 2 |
| Consumer Confidence Report Rule | Reporting | 15 | 2 |
| Lead | Inorganic | 12 | 2 |
| Lead and Copper Rule | Treatment Technique | 9 | 2 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 85140 | C | 31 | 0 | Epcor - San Tan |
| 85143 | C | 31 | 0 | Epcor - San Tan |
All ZIP Codes in San Tan Valley
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.
CDC Health Data for San Tan Valley
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Key Contaminants Detected in San Tan Valley
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Old Is San Tan Valley's Housing Stock?
Housing age data helps assess potential lead pipe and infrastructure risks. Newer housing stock generally means lower plumbing-related contamination risk.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
A post-1986 majority in San Tan Valley's housing inventory — median build year 2004 — generally signals lower aggregate plumbing-era lead risk.
Most homes in San Tan Valley were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
San Tan Valley: Remediation Cost in Perspective
The household financial picture for San Tan Valley homeowners is proportionally favorable — addressing documented issues claims a small slice of equity, and the cost-to-value ratio puts this area well within the manageable tier.
Remediation costs in San Tan Valley are relatively low compared to home values. The $1,200–$3,300 estimated range is a small fraction of median property value. Home values are 35% above the Arizona average.
Protecting Children from Lead in San Tan Valley
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
In San Tan Valley, the older-stock footprint runs at 4% — a contained slice — and aggregate utility readings land safely under the EPA action mark. That keeps lead off the local priority list, with a one-faucet draw remaining the only direct read on a specific address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for San Tan Valley
Measured across the NFIP's multi-decade tracking period, San Tan Valley shows a moderate flood record — 3 claims and 100% of ZIP codes carrying FEMA flood zone status. For water quality, that combination matters because flood events at this frequency can periodically stress infrastructure: treatment plants, private wells, and distribution systems all face elevated risk during significant flooding.
San Tan Valley has a moderate flood history with 3 FEMA claims. 100% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$2,200</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in San Tan Valley
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Revised Total Coliform Rule can reduce the most common contaminant found in San Tan Valley's water.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for San Tan Valley, AZ