Water Quality in Paso Robles, CA: 16 Violations — Grade D
Grade D · Score 50/100 · 5 water systems · Updated 2026-05-03
Paso Robles's water has significant violations. Water testing and filtration are recommended.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
According to EPA filings, Paso Robles, CA has 16 water compliance violations on record — sourced from SDWIS, the federal database that tracks reportable events for every registered public water system in the state.
Water Quality by ZIP Code in Paso Robles
Water quality varies across Paso Robles's 2 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 93447 | D | 48 | 8 | 8 | View report → |
| 93446 | D | 51 | 8 | 8 | View report → |
Violation Trend
EPA violations recorded for water systems serving Paso Robles.
Water Quality Overview
Paso Robles, California receives a water quality grade of D with an overall score of 50 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Paso Robles have accumulated 16 EPA violations, including 16 health-based violations. These violations are tracked across 2 ZIP codes serving approximately 35,658 people.
What Grade D Means
A grade of D indicates significant compliance issues. Paso Robles's water systems have accumulated violations that suggest ongoing water quality challenges. Residents should check their specific ZIP code report and consider water testing or filtration.
Lead Levels
The average 90th percentile lead level across Paso Robles water systems is 0.0058 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 46% of homes built before 1986, Paso Robles 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
Paso Robles is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Paso Robles
Paso Robles is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 35,658 people across 2 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 20 enforcement actions against water systems serving Paso Robles. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Paso Robles
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 Paso Robles Water Systems
The following contaminants have been detected or caused violations across Paso Robles's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 14 | 2 | Yes |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 0.06 mg/L | 2 | 2 | Yes |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Violation Trend Over Time
Year-by-year EPA violations recorded for water systems serving Paso Robles:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2021 | 2 | 2 |
| 2022 | 8 | 8 |
| 2023 | 10 | 10 |
| 2024 | 4 | 4 |
Violations have increased from 2 in 2021 to 4 in 2024. This trend warrants monitoring.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving Paso Robles. Recent actions:
| Date | Action Type |
|---|---|
| 2024-06-19 | State Order Extension |
| 2024-04-15 | State Filed Suit |
| 2024-02-27 | State Filed Suit |
| 2023-10-11 | State Filed Suit |
| 2023-08-14 | State Filed Suit |
| 2023-07-19 | State Order Extension |
| 2023-01-11 | State Filed Suit |
| 2022-11-08 | State Filed Suit |
| 2022-10-04 | State Filed Suit |
| 2022-05-31 | State Filed Suit |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2024-06-19.
Paso Robles vs. Nearby California Cities
How Paso Robles's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Paso Robles | D | 16 | 5 | 35,658 |
| Lakeside | B | 2 | 1 | 35,500 |
| La Crescenta | B | 0 | 1 | 35,841 |
| Verdugo City | C | 0 | 1 | 35,841 |
Common Questions About Paso Robles Water
These are the most common questions residents search for about water quality in Paso Robles, California:
Is Paso Robles water hard or soft? Water hardness varies by source. Paso Robles's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Paso Robles tap water? Paso Robles's water receives a grade of D (50/100). There are 16 health-based violations — consider filtration.
What is the best water filter for Paso Robles? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Paso Robles vs. California Average
Understanding how Paso Robles 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 Paso Robles.
ZIP Codes in Paso Robles
Paso Robles spans 2 ZIP codes. The ZIP with the lowest water quality score is 93446. 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.