El Sobrante, CA Water Safety: 66/100 (2026)
2 ZIP codes · 2 water systems · Updated 2026-06-03
El Sobrante, CA: middle-tier water safety by the latest federal monitoring.
How El Sobrante Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About El Sobrante Water
- Estimated remediation: $2,300 per household.
- CDC health risk index: 10.72.
Who Supplies Your Water in El Sobrante
Across El Sobrante, CA, residential water comes from 2 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 2 water systems in the area, with these top providers accounting for the majority of residential connections.
Overview
We track water quality and home safety data for 2 ZIP codes in El Sobrante, California (population ~27,588), covering 2 community water systems serving approximately 1,442,951 people region-wide.
No EPA violations recorded across any ZIP codes in El Sobrante — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for El Sobrante: C (66/100)
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
El Sobrante water systems draw from: Groundwater.
Lead & Copper
- Lead data: not yet available for El Sobrante
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 3 (Low Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 2 ZIP codes
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 94803 | C | EAST BAY MUD | 1,442,800 |
| 94820 | C | SONOMA RANCH MUTUAL WATER COMPANY | 151 |
All ZIP Codes in El Sobrante
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.
Health Outcomes in El Sobrante
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
Cost Context: What Remediation Means for El Sobrante Homeowners
The household financial picture for El Sobrante homeowners is proportionally favorable — addressing documented issues claims a small slice of equity, and the cost-to-value ratio puts this area well within the manageable tier.
Remediation costs in El Sobrante are relatively low compared to home values. The $1,500–$3,300 estimated range is a small fraction of median property value. Home values are 1% below the California average.
Flood & Climate Risk in El Sobrante
40 FEMA flood insurance claims are on file for El Sobrante, and 50% of local ZIP codes fall within federally designated flood zones — enough to put flood exposure on the planning radar, though short of the concentrated-risk threshold where treatment-system vulnerability becomes a primary consideration.
El Sobrante has a moderate flood history with 40 FEMA claims averaging $21,892 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>$2,300</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 El Sobrante
- 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. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for El Sobrante, CA