Oak Park, CA: High Radon Risk — 45/100 (2026)
1 ZIP code · 3 water systems · Updated 2026-06-03
Unlike better-scoring cities in CA, Oak Park records health-based violations across a meaningful portion of its service areas — the overall safety grade is well below average.
How Oak Park Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Oak Park Residents
- Homes built before 1986: 52% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 10.84.
Oak Park's Water Providers
3 independent water providers serve Oak Park, CA — 3 systems appear in federal records.
Overview
We track water quality and home safety data for 1 ZIP code in Oak Park, California (population ~13,656), covering 3 community water systems serving approximately 67,055 people region-wide.
No EPA violations recorded across any ZIP codes in Oak Park — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Oak Park: D (45/100)
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
Oak Park water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Oak Park
- 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.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 91377 | D | Triunfo Water & Sanitation District | 13,898 |
All ZIP Codes in Oak Park
- 91377 [D]
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.
Oak Park Community Health Snapshot
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
Oak Park Infrastructure Age
With 52% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Lead solder was standard in copper plumbing until federally banned in 1986; lead pipes were common in service lines pre-1970. Oak Park's median build year of 1984 reflects a housing stock where these older materials are a pervasive feature — not a rare legacy — of the residential plumbing landscape.
Over half of homes in Oak Park were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Oak Park
For most homeowners in Oak Park, the estimated cost of water and safety remediation represents a proportionally modest share of what properties are worth — placing this area in the lower tier of the remediation share scale.
Remediation costs in Oak Park are relatively low compared to home values. The $1,600–$3,300 estimated range is a small fraction of median property value. Home values are 38% above the California average.
Oak Park: Lead Risk & Vulnerable Populations
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.
After the federal action removing lead-bearing solder from new plumbing took effect, building practice shifted — but 52% of the Oak Park inventory predates that line. With aggregate samples near or beyond 0.015 mg/L, an in-home check moves out of the optional column into the standard list.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Oak Park: Flood History & Water Damage Risk
Measured across the NFIP's multi-decade tracking period, Oak Park shows a moderate flood record — 14 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.
Oak Park has a moderate flood history with 14 FEMA claims averaging $11,985 per payout. 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>$2,400</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 Oak Park
- 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. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 52% of homes built before 1986, lead solder is a real possibility.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Oak Park, CA