Merced, CA: 5 Health Violations — 81/100 (2026)
5 ZIP codes · 5 water systems · Updated 2026-06-03
Compared to statewide averages in CA, Merced scores well — health violations are below the norm and systems generally operate within federal standards.
How Merced Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Merced, CA
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
How ZIP codes in Merced score across all safety grades.
What You Should Know About Merced Water
- Your city's water systems recorded 25 violations in the past 5 years.
- Average lead level: 0.0069 mg/L.
- Homes built before 1986: 56% — older plumbing may contain lead solder.
- Estimated remediation: $1,620 per household.
- CDC health risk index: 12.06 — above typical levels.
Who Supplies Your Water in Merced
5 water systems are tracked federally in Merced, CA. The top 3 providers collectively serve most residential addresses, but because they operate independently, infrastructure maintenance standards and compliance histories differ from one service zone to another.
Overview
We track water quality and home safety data for 5 ZIP codes in Merced, California, covering 5 community water systems serving approximately 109,664 people.
5 of 5 ZIP codes (100%) have recorded EPA violations. 5 health-based violations documented.
Home Safety Score
Average Home Safety Score for Merced: B (81/100)
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
Merced water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0069 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 3 (Low Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 5 ZIP codes
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 2 DBP Rule | Treatment Technique | 12 | 5 |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 6 | 5 |
| Stage 1 DBP Rule | Treatment Technique | 6 | 5 |
| Consumer Confidence Report Rule | Reporting | 6 | 5 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 95340 | B | 5 | 1 | City of Merced |
| 95341 | B | 5 | 1 | City of Merced |
| 95343 | A | 5 | 1 | City of Merced |
| 95344 | A | 5 | 1 | City of Merced |
| 95348 | B | 5 | 1 | City of Merced |
All ZIP Codes in Merced
- 95340 [B] — 5 violations ⚠
- 95341 [B] — 5 violations ⚠
- 95343 [A] — 5 violations ⚠
- 95344 [A] — 5 violations ⚠
- 95348 [B] — 5 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 Merced
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 Merced Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Housing & Infrastructure in Merced
With 56% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
For residents trying to assess tap water risk in Merced, the median build year of 1981 is the starting context. It signals that a majority of homes were constructed before 1986 — the year federal rules prohibited lead solder in new plumbing — and that a significant share likely predates 1970, when lead pipes were still a common choice for residential service connections. Neither risk tier is rare in this housing inventory.
Over half of homes in Merced were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Merced Homeowners
Placing remediation in the context of Merced's property market, the equity share is low — most homeowners here are weighing a financial commitment that fits comfortably within routine property planning, far from the threshold where remediation becomes a material equity decision rather than a standard upkeep consideration.
Remediation costs in Merced are relatively low compared to home values. The $1,030–$2,440 estimated range is a small fraction of median property value. Home values are 52% below the California average.
Lead Exposure Risk for Children in Merced
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.
Before the federal solder ban, lead solder was a routine plumbing material, and 56% of the Merced inventory was built in that earlier era — a share large enough to move household-level reads onto the standard list.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Merced
Flood exposure in Merced is meaningful by NFIP measures — 408 claims on record and 60% of ZIP codes carrying FEMA flood zone designations. That level of activity makes flood history a relevant factor when evaluating local water quality over time.
Merced has a moderate flood history with 408 FEMA claims averaging $22,816 per payout. 60% 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>$1,620</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.
Deep Dive Reports
Detailed analysis for Merced, CA