Westlake Village, CA: High Radon Risk — 73/100 (2026)
2 ZIP codes · 7 water systems · Updated 2026-06-03
In current tracking cycles, Westlake Village records above-average water quality outcomes for CA; compliance history over recent years shows few departures from federal standards and no systemic failures across its water systems.
How Westlake Village Compares
Data: EPA SDWIS Last verified: 2026-06-03
Westlake Village Water: The Quick Version
- Average lead level: 0.0053 mg/L.
- Estimated remediation: $1,000 per household.
- CDC health risk index: 10.78.
Water Systems Serving Westlake Village
7 water systems are tracked federally in Westlake Village, CA. The top 3 providers collectively serve most residential addresses, but because they operate independently, infrastructure maintenance standards and compliance histories differ from one service zone to another.
Overview
We track water quality and home safety data for 2 ZIP codes in Westlake Village, California (population ~18,728), covering 7 community water systems serving approximately 208,250 people region-wide.
No EPA violations recorded across any ZIP codes in Westlake Village — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Westlake Village: B (73/100)
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
Westlake Village water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0053 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
- Zone 1 (High): 1 ZIP code
- Zone 2 (Moderate): 1 ZIP code
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 91359 | B | Triunfo Water & Sanitation District | 13,898 |
| 91361 | C | LAS VIRGENES MWD | 72,602 |
All ZIP Codes in Westlake Village
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 Westlake Village
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
Westlake Village: Remediation Cost in Perspective
Setting Westlake Village remediation figures against its property market, the resulting ratio sits comfortably in the low tier — a classification that reflects the kind of household financial position where most homeowners can identify documented issues, schedule the work, and absorb the cost without it registering as a significant budget disruption.
Remediation costs in Westlake Village are relatively low compared to home values. The $400–$1,700 estimated range is a small fraction of median property value. Home values are 80% above the California average.
Protecting Children from Lead in Westlake Village
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.
Lead risk in Westlake Village appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Westlake Village
NFIP records stretching across multiple decades show Westlake Village accumulating 35 claims and carrying 50% of its ZIP codes inside FEMA flood zones — evidence of meaningful exposure that extends beyond isolated incidents. The mechanisms linking flooding to water quality haven't changed: treatment facilities can be overwhelmed, wells can be infiltrated, and distribution systems can experience backflow. For a community at this exposure level, those mechanisms shift from hypothetical to periodically relevant.
Westlake Village has a moderate flood history with 35 FEMA claims averaging $5,501 per payout. 50% 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>$1,000</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.
Deep Dive Reports
Detailed analysis for Westlake Village, CA