Water Quality in Redwood City, CA: No Violations - Grade N/A
5 water systems · 4 directly mapped ZIP records
Available EPA records report no violations across 4 directly mapped ZIP records with known counts for Redwood City. This does not cover unavailable records or guarantee a specific tap is contaminant-free.
Data: EPA Safe Drinking Water Information System (SDWIS)
Water Quality by ZIP Code in Redwood City
This table shows typed EPA water evidence only. Missing violation counts are displayed as N/A, not zero.
| ZIP Code | Violations | Health | |
|---|---|---|---|
| 94061 | 0 | 0 | View report → |
| 94062 | 0 | 0 | View report → |
| 94063 | 0 | 0 | View report → |
| 94065 | 0 | 0 | View report → |
Water Quality Overview
Redwood City, California has directly mapped EPA water-system data for 4 ZIP codes. This page reports typed compliance facts and does not relabel the multi-source Home Safety Score as a drinking-water grade.
The available EPA records report no violations across 4 directly mapped ZIP records with reported counts for Redwood City. This does not guarantee the absence of contaminants.
Lead Levels
The average 90th percentile lead level across Redwood City water systems is 0.0035 mg/L - within EPA limits. No exceedances appear among the 4 ZIP records with known lead status.
With 69% of homes built before 1986, Redwood City has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Water Systems Serving Redwood City
Redwood City is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 109,628 people across 5 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
How to Check Your Water in Redwood City
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels and violation history
Request your CCR - your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test - certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration - NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories - monitor your local utility website and local news for boil water advisories or system alerts
Redwood City vs. Nearby California Cities
How Redwood City's water quality compares to similar cities in California:
| City | Direct EPA ZIPs | Violations | Systems | Population |
|---|---|---|---|---|
| Redwood City | 4 | 0 | 5 | 109,628 |
| Merced | 3 | 2 | 3 | 109,664 |
| San Leandro | 3 | 0 | 3 | 109,055 |
| West Covina | 3 | 1 | 9 | 109,033 |
Water Quality by ZIP Code in Redwood City
EPA coverage and recorded violations can differ across Redwood City's ZIP codes. Missing counts are shown as unavailable, not zero:
Common Questions About Redwood City Water
These are the most common questions residents search for about water quality in Redwood City, California:
Is Redwood City water hard or soft? Water hardness varies by source. Redwood City's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Redwood City tap water? City-level EPA records cannot determine safety at a specific tap. No health-based violations are recorded across 4 directly mapped ZIP records with known counts, but this is not a property-level safety guarantee.
What is the best water filter for Redwood City? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Redwood City vs. California Average
Understanding how Redwood City compares to the broader California average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below - water quality can vary significantly even within Redwood City.
ZIP Codes in Redwood City
Redwood City spans 5 ZIP codes. EPA water-system coverage is available for 4 directly mapped ZIP codes. Check each ZIP code for detailed contaminant data, violation history, and system information.
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
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Source reporting periods vary. See each cited source for its publication schedule.