Guerneville, CA Water Safety: 67/100 (2026)
1 ZIP code · 6 water systems · Updated 2026-06-03
Across water systems in Guerneville, 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 CA.
How Guerneville Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Guerneville Residents
- Homes built before 1986: 81% — older plumbing may contain lead solder.
- Estimated remediation: $1,200 per household.
- CDC health risk index: 11.32.
Guerneville's Water Providers
Water service in Guerneville, CA is split across 3 utilities out of 6 tracked federally, each operating its own infrastructure and compliance record.
Overview
We track water quality and home safety data for 1 ZIP code in Guerneville, California (population ~4,808), covering 6 community water systems serving approximately 17,773 people region-wide.
No EPA violations recorded across any ZIP codes in Guerneville — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Guerneville: C (67/100)
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
Guerneville water systems draw from: Groundwater.
Lead & Copper
- Lead data: not yet available for Guerneville
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 3 (Low Risk)
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 95446 | C | Sweetwater Springs Cwd - Guerneville | 6,000 |
All ZIP Codes in Guerneville
- 95446 [C]
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.
Guerneville 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
Guerneville Infrastructure Age
With 81% 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
Two dates define the high-risk tiers of residential plumbing from a lead standpoint: 1970, before which lead pipes were commonly installed for service connections, and 1986, before which lead solder was standard in copper plumbing. A median build year of 1952 places Guerneville's housing distribution well within that older risk zone. The bar chart above breaks down how much of the stock falls into each era — and the pre-1986 share alone represents more than half the residential inventory, making plumbing-era risk a defining characteristic of the local water safety picture.
Over half of homes in Guerneville 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 Guerneville
In Guerneville, property values comfortably outpace what documented remediation typically costs — the equity share is proportionally low.
Remediation costs in Guerneville are relatively low compared to home values. The $800–$1,800 estimated range is a small fraction of median property value. Home values are 21% below the California average.
Guerneville: 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.
Although utility-side compliance with federal Lead and Copper requirements remains the system reference, that compliance does not extend down into interior plumbing. With 81% of Guerneville stock built before the solder ban and aggregate readings at or beyond the action mark, a household-level sample becomes the practical way to close that information gap.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Guerneville: Flood History & Water Damage Risk
Measured against the full NFIP dataset, Guerneville's flood record stands out: 3952 claims accumulated over decades and 100% of ZIP codes inside FEMA-designated boundaries add up to a high-exposure profile where water infrastructure has faced recurrent stress.
Guerneville has a significant flood history with 3,952 FEMA flood insurance claims on record, averaging $17,578 per claim. With 100% of ZIP codes in FEMA-designated flood zones, flood risk is a major concern for homeowners and water quality.
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>$1,200</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 Guerneville
- 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 81% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Guerneville, CA