Walnut, CA: 1 Violation - Home Safety 58/100
3 ZIP codes · 5 water systems · Updated
ZipCheckup grade for Walnut: C.
A mixed picture - some signals here are worth your attention.
For most households in Walnut, CA tap water is adequate - the middle-tier grade reflects gaps in specific service areas.
How Walnut Compares
Data: EPA SDWIS
Key Facts for Walnut Residents
- Your city's water systems recorded 1 violation in the past 5 years.
- Average lead level: 0.0021 mg/L.
- Estimated remediation: $1,000 per household.
- CDC health risk index: 10.71.
Walnut's Water Providers
Across Walnut, CA, residential water comes from 3 primary utilities rather than a single consolidated provider. Each system operates independently - managing its own distribution infrastructure, rate schedules, and EPA compliance filings. Federal records track 5 water systems in the area, with these top providers accounting for the majority of residential connections.
- C
- C
- C
Overview
We track home safety data for 3 ZIP codes in Walnut, California (population ~40,933), covering 5 community water systems serving approximately 534,135 people region-wide. The EPA snapshots used for this build directly map water systems to 1 of 3 ZIP codes.
1 of 1 ZIP code 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 Walnut: C (58/100)
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
Walnut water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0021 mg/L (EPA action level: 0.015 mg/L)
- 0 of 1 ZIP code 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): 3 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 |
|---|---|---|---|
| Consumer Confidence Report Rule | Reporting | 2 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 91789 | C | 1 | 0 | Walnut Valley Water District |
All ZIP Codes in Walnut
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.
Walnut 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
What's in Walnut's Water?
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Remediation Costs Compare in Walnut
At current valuations, Walnut sits in the low remediation-share tier - the equity impact of fixing documented issues is proportionally minor.
Remediation costs in Walnut are relatively low compared to home values. The $400–$1,667 estimated range is a small fraction of median property value. Home values are 27% above the California average.
Walnut: 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.
Lead risk in Walnut 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.
Walnut: NFIP Claim Records and Water-Quality Context
Historical NFIP data for Walnut contains 7 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $457. Among ZIP codes with claim records, 100% 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>$1,000</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.
What You Can Do in Walnut
- 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 Consumer Confidence Report Rule can reduce the most common contaminant found in Walnut'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 Walnut, CA