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.

Data: EPA SDWIS

Overview

We track home safety data for 2 ZIP codes in San Tan Valley, Arizona (population ~92,595), covering 2 community water systems serving approximately 182,937 people region-wide. The EPA snapshots used for this build directly map water systems to 2 of 2 ZIP codes.

2 of 2 ZIP codes with a reported violation count in the available EPA record (100%) have recorded EPA violations. The available record reports no health-based violations for this measured scope.

Home Safety Score

Average Home Safety Score for San Tan Valley: C (65/100)

Model 4.0.0 uses four measured components across three equally weighted domains. If a required domain is unavailable, no score is published:

Factor	What It Measures
Water Quality	EPA violations and compliance history
PFAS MCL Screen	UCMR 5 testing against the covered federal MCLs
Radon Risk	EPA radon zone classification
Annual AQI	EPA AirData county-year median with at least 90 observed days

Water Sources

San Tan Valley water systems draw from: Groundwater.

Lead & Copper

• Average lead level (90th percentile): 0.0000 mg/L (EPA action level: 0.015 mg/L)
• 0 of 2 ZIP codes with known status 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

Areas with Most Violations

All ZIP Codes in San Tan Valley

• 85140 [C] - 35 violations
• 85143 [C] - 32 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

Reporting periods vary by source. Missing data is shown as unavailable, not as zero.

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.

2004

Median Year Built

4%

Pre-1986 (Lead Paint Risk)

0%

Pre-1970 (Lead Pipes Risk)

Pre-1970 (0%) 1970–1986 (4%) Post-1986 (96%)

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.

Median Home Value

$411,800

Est. Remediation

$2,200

Remediation as % of home value 0.5%

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

4%

Homes Built Before 1986

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.

Historical Flood-Claim Evidence for San Tan Valley

3

Total FEMA Flood Claims

$0

Avg Reported Sum With Payment Data

0%

A/V Share of Claim-Record ZIPs

Historical NFIP data for San Tan Valley contains 3 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $0. Among ZIP codes with claim records, 0% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.

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. The <strong>$2,200</strong> remediation estimate shown here excludes flood insurance and is not derived from NFIP claim count.

Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.

Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.