Water Quality in Sunnyvale, CA: No Violations — Grade B
Grade B · Score 74/100 · 1 water system · Updated 2026-05-03
Sunnyvale's water is mostly safe. Minor violations exist but are primarily monitoring-related.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
For households in Sunnyvale, CA, the EPA compliance record offers a straightforward finding: 1 water system are on file, zero violations documented across the entire dataset, and no regulatory actions have been taken against any local utility under the federal Safe Drinking Water Act in any reporting period covered by available SDWIS data.
Water Quality Map: Sunnyvale, CA
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Sunnyvale
Water quality varies across Sunnyvale's 5 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 94088 | B | 72 | 0 | 0 | View report → |
| 94085 | B | 75 | 0 | 0 | View report → |
| 94086 | B | 75 | 0 | 0 | View report → |
| 94087 | B | 75 | 0 | 0 | View report → |
| 94089 | B | 75 | 0 | 0 | View report → |
Water Quality Overview
Sunnyvale, California receives a water quality grade of B with an overall score of 74 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
No EPA violations have been recorded for the 1 water system serving Sunnyvale. This is a positive indicator, though it does not guarantee the absence of all contaminants — some substances (like PFAS) are not yet fully regulated.
What Grade B Means
A grade of B indicates good compliance with EPA drinking water standards. While not perfect, Sunnyvale's water systems meet the vast majority of federal requirements. Minor violations may exist but typically relate to monitoring or reporting rather than health-based standards.
Lead Levels
Lead testing data for Sunnyvale is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
With 62% of homes built before 1986, Sunnyvale 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.
Radon Risk
Sunnyvale is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Sunnyvale
Sunnyvale is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 157,566 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
The EPA has taken 10 enforcement actions against water systems serving Sunnyvale. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Sunnyvale
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
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
EPA Enforcement History
The EPA and state regulators have taken 2 enforcement actions against water systems serving Sunnyvale. Recent actions:
| Date | Action Type |
|---|---|
| 2024-02-28 | State Filed Judgment |
| 2024-02-28 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2024-02-28.
Sunnyvale vs. Nearby California Cities
How Sunnyvale's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Sunnyvale | B | 0 | 1 | 157,566 |
| San Dimas | A | 0 | 5 | 156,943 |
| Rialto | B | 0 | 2 | 158,951 |
| Roseville | B | 3 | 5 | 155,825 |
Recommended Water Filters for Sunnyvale
Based on contaminants detected in Sunnyvale's water supply, these filter types are recommended:
Granular Activated Carbon (GAC, whole-house or under-sink)
- Removes: Disinfectant Residual as Chlorine
- Effectiveness: 95-99%
- Cost range: $100–$600
- Certification: NSF/ANSI 42
- Recommended products:
- Aquasana AQ-5200
- Waterdrop Chubby Pitcher
- Berkey Travel
Granular Activated Carbon (GAC, whole-house POE)
- Removes: Total Trihalomethanes
- Effectiveness: 80-99%
- Cost range: $400–$2000
- Certification: NSF/ANSI 53
- Recommended products:
Granular Activated Carbon (GAC, under-sink or whole-house)
- Removes: Haloacetic Acids
- Effectiveness: 60-80%
- Cost range: $100–$600
- Certification: NSF/ANSI 53
- Recommended products:
Water Quality by ZIP Code in Sunnyvale
Water quality varies across Sunnyvale's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 94088 | 72 | B | 0 | 0 |
| 94085 | 75 | B | 0 | 0 |
| 94086 | 75 | B | 0 | 0 |
| 94087 | 75 | B | 0 | 0 |
| 94089 | 75 | B | 0 | 0 |
Common Questions About Sunnyvale Water
These are the most common questions residents search for about water quality in Sunnyvale, California:
Is Sunnyvale water hard or soft? Water hardness varies by source. Sunnyvale's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Sunnyvale tap water? Sunnyvale's water receives a grade of B (74/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Sunnyvale? Based on detected contaminants, a granular activated carbon (gac, whole-house or under-sink) filter is most recommended. See our Water Filter Matcher for personalized recommendations.
Sunnyvale vs. California Average
Understanding how Sunnyvale 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 Sunnyvale.
ZIP Codes in Sunnyvale
Sunnyvale spans 5 ZIP codes. Each ZIP code has its own water quality profile based on the specific water system serving that area. 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
Updated daily.
Frequently Asked Questions
Your Water is Safe — Here's How to Keep It That Way
Grade B is excellent news. Here's what proactive homeowners do to maintain water quality:
Annual Water Testing
EPA recommends annual testing even with clean water. Home test kits: $20-$50. Catches changes before they become problems.
Maintenance Filtration
A basic carbon filter removes chlorine taste and catches emerging contaminants like PFAS that aren't yet fully regulated.
Plumbing Check
Even safe city water picks up lead from home pipes. If your home was built before 1986, a one-time pipe inspection is recommended.