Sonoma, CA: 3 Health Violations - Home Safety 69/100
1 ZIP code · 5 water systems · Updated
ZipCheckup grade for Sonoma: C.
A mixed picture - some signals here are worth your attention.
Sonoma lands in the middle of the grade scale in CA; EPA records can differ from one service area to the next.
How Sonoma Compares
Data: EPA SDWIS
Sonoma Water: The Quick Version
- Your city's water systems recorded 9 violations since 2021.
- Average of reported 90th-percentile lead results: 0.0027 mg/L.
- Homes built before 1986: 69% - older plumbing may contain lead solder.
- Estimated remediation: $1,100 per household.
- Health risk index (ZipCheckup composite of CDC data): 11.32.
Water Systems Serving Sonoma
Among 5 systems linked to Sonoma, CA, the 3 biggest by population served appear below.
- C
- C
- C
Overview
We track home safety data for 1 ZIP code in Sonoma, California, covering 5 community water systems serving approximately 35,139 people. The EPA snapshots used for this build directly map water systems to 1 of 1 ZIP codes.
1 of 1 ZIP code with a reported violation count in the available EPA record (100%) have recorded EPA violations. 3 health-based violations appear in the available health breakdown.
Home Safety Score
Average Home Safety Score for Sonoma: C (69/100)
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
Sonoma water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average of reported 90th-percentile lead results: 0.0027 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
1 of 1 ZIP records with known zones is in EPA Radon Zone 3.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Lead and Copper Rule Revisions | Treatment Technique | 14 | 1 |
| Arsenic | Inorganic | 2 | 1 |
| Revised Total Coliform Rule | Microbiological | 2 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 95476 | C | 9 | 3 | Valley of the Moon Water District |
All ZIP Codes in Sonoma
- 95476 [C] - 9 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.
CDC Health Data for Sonoma
Source: CDC PLACES (County-level estimates). County health indicators are shown for context only and are not linked to this area's water records.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Key Contaminants Detected in Sonoma
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Old Is Sonoma's Housing Stock?
With 69% of homes built before 1986, lead solder in plumbing is a potential concern. Federal law banned lead solder in drinking-water plumbing in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Plumbing risk in older housing is tied to the period before 1986, when lead pipes and lead solder were still permitted in new plumbing. Sonoma's median build year is 1973, and properties from before that year might still contain lead-bearing joints or pipes. Much of that risk sits inside individual properties, which city-level water quality averages don't capture.
Over half of homes in Sonoma were built before 1986, when federal law began restricting lead solder in drinking-water plumbing. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Sonoma: Remediation Cost in Perspective
Measured against the median home value, the estimated cost of fixing the issues flagged for Sonoma lands in the lowest of the three tiers this page uses.
Estimated remediation costs in Sonoma can be compared with local home values. The $600–$2,300 estimated range can be set against the median property value; actual costs vary by home. Home values are 19% above the California average.
Protecting Children from Lead in Sonoma
Why children are most at risk: The CDC states that no safe blood lead level in children has been identified. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
If you have young children or are pregnant, consider testing your home's water - especially if your home was built before 1986.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Historical Flood-Claim Evidence for Sonoma
Historical NFIP data for Sonoma contains 93 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $34,985. 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 $1,100 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 Sonoma
- Test your water at home. City-level data shows averages - your tap may differ. Check the certification, price and turnaround time of any water test kit or lab service.
- Install a certified water filter. For Lead and Copper Rule Revisions, listed in the water-quality records for Sonoma: if it is a rule or reporting requirement rather than a contaminant, ask your utility what the record involved; for bacteria, follow any boil-water notice from your utility; for a specific chemical contaminant, check whether a filter is certified to reduce it. Not every contaminant has a consumer filter certification.
- Check your home's plumbing. With 69% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Sonoma, CA