Lancaster, CA: 114 Health Violations — 40/100 (2026)
6 ZIP codes · 14 water systems · Updated 2026-06-03
If you're researching Lancaster, CA tap water quality, the baseline finding is below average — health-based violations are documented in several service areas, and verifying the specific system at your address is the right next step.
How Lancaster Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Lancaster, CA
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
How ZIP codes in Lancaster score across all safety grades.
What You Should Know About Lancaster Water
- Your city's water systems recorded 144 violations in the past 5 years.
- Average lead level: 0.0092 mg/L.
- Estimated remediation: $1,600 per household.
- CDC health risk index: 10.71.
Who Supplies Your Water in Lancaster
Structurally, Lancaster, CA's water supply is divided. Federal data identifies 14 water systems in the area, with 3 providers serving the bulk of residential connections. These utilities operate independently, meaning rate-setting authority and EPA compliance accountability are distributed rather than centralized.
Overview
We track water quality and home safety data for 6 ZIP codes in Lancaster, California (population ~194,781), covering 14 community water systems serving approximately 367,558 people region-wide.
6 of 6 ZIP codes (100%) have recorded EPA violations. 114 health-based violations documented.
Home Safety Score
Average Home Safety Score for Lancaster: D (40/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Lancaster water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0092 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 6 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Barium | Inorganic | 126 | 6 |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 14 | 6 |
| Total Coliform | Microbiological | 7 | 6 |
| Stage 1 DBP Rule | Treatment Technique | 7 | 6 |
| Consumer Confidence Report Rule | Reporting | 7 | 6 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 93534 | D | 24 | 19 | Land Projects Mutual Water Company |
| 93535 | D | 24 | 19 | Averydale Mwc |
| 93536 | D | 24 | 19 | Land Projects Mutual Water Company |
| 93539 | F | 24 | 19 | Land Projects Mutual Water Company |
| 93584 | F | 24 | 19 | Land Projects Mutual Water Company |
| 93586 | F | 24 | 19 | Land Projects Mutual Water Company |
All ZIP Codes in Lancaster
- 93534 [D] — 24 violations ⚠
- 93535 [D] — 24 violations ⚠
- 93536 [D] — 24 violations ⚠
- 93539 [F] — 24 violations ⚠
- 93584 [F] — 24 violations ⚠
- 93586 [F] — 24 violations ⚠
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
Updated daily.
Health Outcomes in Lancaster
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Top Contaminants in Lancaster Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Cost Context: What Remediation Means for Lancaster Homeowners
Equity impact data for Lancaster lands in the favorable tier — remediation claims a small slice of what properties here are worth.
Remediation costs in Lancaster are relatively low compared to home values. The $700–$3,200 estimated range is a small fraction of median property value. Home values are 54% below the California average.
Lead Exposure Risk for Children in Lancaster
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Lead risk in Lancaster appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Lancaster
The National Flood Insurance Program captures decades of claims at the local level, building a record of cumulative community flood exposure. For Lancaster, that record documents 43 claims and 50% of ZIP codes inside FEMA-designated flood zones. What makes those numbers relevant to water quality is the set of mechanisms flooding activates: heavy precipitation that floods treatment intake zones can introduce contaminants upstream of normal filtration; well casings in low-lying areas can be infiltrated by floodwaters carrying bacteria, sediment, and chemical residue; and distribution system pressure changes during flooding can create backflow conditions. These effects become more probable as flood frequency and magnitude increase — and the NFIP record indicates both are meaningful factors locally.
Lancaster has a moderate flood history with 43 FEMA claims averaging $12,093 per payout. 50% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,600</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Lancaster
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Barium can reduce the most common contaminant found in Lancaster's water.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Lancaster, CA