Water Quality in Los Angeles, CA: 190 Violations — Grade B
Grade B · Score 77/100 · 5 water systems · Updated 2026-05-03
Los Angeles'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
Tracked under the EPA Safe Drinking Water program, Los Angeles, CA shows 190 water violations on file — findings that span multiple violation categories and are detailed system by system in the data grid further down the page.
Water Quality Map: Los Angeles, CA
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Los Angeles
Water quality varies across Los Angeles's 95 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 90046 | C | 64 | 2 | 1 | View report → |
| 90049 | C | 64 | 2 | 1 | View report → |
| 90077 | C | 64 | 2 | 1 | View report → |
| 90016 | C | 69 | 2 | 1 | View report → |
| 90019 | C | 69 | 2 | 1 | View report → |
| 90035 | C | 69 | 2 | 1 | View report → |
| 90047 | C | 69 | 2 | 1 | View report → |
| 90048 | C | 69 | 2 | 1 | View report → |
| 90068 | C | 69 | 2 | 1 | View report → |
| 90004 | B | 74 | 2 | 1 | View report → |
| 90005 | B | 74 | 2 | 1 | View report → |
| 90008 | B | 74 | 2 | 1 | View report → |
| 90014 | B | 74 | 2 | 1 | View report → |
| 90024 | B | 74 | 2 | 1 | View report → |
| 90025 | B | 74 | 2 | 1 | View report → |
Water Quality Overview
Los Angeles, California receives a water quality grade of B with an overall score of 77 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Los Angeles have accumulated 190 EPA violations, including 95 health-based violations. These violations are tracked across 95 ZIP codes serving approximately 4,028,484 people.
What Grade B Means
A grade of B indicates good compliance with EPA drinking water standards. While not perfect, Los Angeles'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
The average 90th percentile lead level across Los Angeles water systems is 0.0039 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 80% of homes built before 1986, Los Angeles 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
Los Angeles is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Los Angeles
Los Angeles is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 4,028,484 people across 95 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 95 enforcement actions against water systems serving Los Angeles. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Los Angeles
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 Los Angeles Water Systems
The following contaminants have been detected or caused violations across Los Angeles's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Stage 2 DBP Rule | Treatment Technique | N/A | 190 | 95 | Yes |
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 1 enforcement action against water systems serving Los Angeles. Recent actions:
| Date | Action Type |
|---|---|
| 2024-12-16 | EPA Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2024-12-16.
Los Angeles vs. Nearby California Cities
How Los Angeles's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Los Angeles | B | 190 | 5 | 4,028,484 |
| Studio City | D | 0 | 2 | 3,981,169 |
| Sherman Oaks | D | 0 | 2 | 3,875,648 |
| Culver City | C | 0 | 1 | 3,875,566 |
Water Quality by ZIP Code in Los Angeles
Water quality varies across Los Angeles's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 90046 | 64 | C | 2 | 1 |
| 90049 | 64 | C | 2 | 1 |
| 90077 | 64 | C | 2 | 1 |
| 90016 | 69 | C | 2 | 1 |
| 90019 | 69 | C | 2 | 1 |
| 90035 | 69 | C | 2 | 1 |
| 90047 | 69 | C | 2 | 1 |
| 90048 | 69 | C | 2 | 1 |
| 90068 | 69 | C | 2 | 1 |
| 90004 | 74 | B | 2 | 1 |
| 90084 | 79 | B | 2 | 1 |
| 90078 | 79 | B | 2 | 1 |
| 90071 | 79 | B | 2 | 1 |
| 90063 | 79 | B | 2 | 1 |
| 90062 | 79 | B | 2 | 1 |
Common Questions About Los Angeles Water
These are the most common questions residents search for about water quality in Los Angeles, California:
Is Los Angeles water hard or soft? Water hardness varies by source. Los Angeles's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Los Angeles tap water? Los Angeles's water receives a grade of B (77/100). There are 95 health-based violations — consider filtration.
What is the best water filter for Los Angeles? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Los Angeles vs. California Average
Understanding how Los Angeles 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 Los Angeles.
ZIP Codes in Los Angeles
Los Angeles spans 95 ZIP codes. The ZIP with the lowest water quality score is 90001. 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.