Water Quality in Boulder Creek, CA: 7 Violations — Grade C
Grade C · Score 65/100 · 5 water systems · Updated 2026-05-03
Boulder Creek's water has moderate compliance issues. Residents in affected areas should consider filtration.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
EPA monitoring has flagged 7 reportable events for water systems in Boulder Creek, CA.
Water Quality by ZIP Code in Boulder Creek
Water quality varies across Boulder Creek's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 95006 | C | 65 | 7 | 2 | View report → |
Water Quality Overview
Boulder Creek, California receives a water quality grade of C with an overall score of 65 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Boulder Creek have accumulated 7 EPA violations, including 2 health-based violations. These violations are tracked across 1 ZIP codes serving approximately 25,972 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Boulder Creek's water systems have some violations that warrant attention. While the water may still be safe for most people, residents in affected ZIP codes should consider additional testing or filtration.
Lead Levels
The average 90th percentile lead level across Boulder Creek water systems is 0.0043 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 82% of homes built before 1986, Boulder Creek 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
Boulder Creek is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Boulder Creek
Boulder Creek is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 25,972 people across 1 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 Boulder Creek. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Boulder Creek
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
Contaminants Detected in Boulder Creek Water Systems
The following contaminants have been detected or caused violations across Boulder Creek's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Stage 2 DBP Rule | Treatment Technique | N/A | 4 | 1 | Yes |
| Surface Water Treatment Rule | Treatment Technique | N/A | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving Boulder Creek. Recent actions:
| Date | Action Type |
|---|---|
| 2025-02-19 | State Filed Suit |
| 2024-12-11 | State Order Extension |
| 2023-10-19 | State Filed Suit |
| 2023-04-20 | State Order Extension |
| 2023-03-20 | State Filed Suit |
| 2022-11-08 | State Order Extension |
| 2022-04-08 | State Order Extension |
| 2022-03-24 | State Filed Suit |
| 2022-03-03 | State Filed Suit |
| 2021-11-16 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-02-19.
Boulder Creek vs. Nearby California Cities
How Boulder Creek's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Boulder Creek | C | 7 | 5 | 25,972 |
| Oakdale | B | 2 | 5 | 25,595 |
| Windsor | B | 0 | 1 | 25,561 |
| Landers | D | 0 | 1 | 26,411 |
Common Questions About Boulder Creek Water
These are the most common questions residents search for about water quality in Boulder Creek, California:
Is Boulder Creek water hard or soft? Water hardness varies by source. Boulder Creek's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Boulder Creek tap water? Boulder Creek's water receives a grade of C (65/100). There are 2 health-based violations — consider filtration.
What is the best water filter for Boulder Creek? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Boulder Creek vs. California Average
Understanding how Boulder Creek 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 Boulder Creek.
ZIP Codes in Boulder Creek
Boulder Creek spans 1 ZIP code. The ZIP with the lowest water quality score is 95006. 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.