Glendora, CA: 2 Violations — 83/100 (2026)
2 ZIP codes · 5 water systems · Updated 2026-06-03
Although water quality varies across any metro, Glendora's systems collectively post above-average compliance scores for CA — and documented violations are few.
How Glendora Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Glendora Residents
- Your city's water systems recorded 2 violations in the past 5 years.
- Average lead level: 0.0035 mg/L.
- Homes built before 1986: 85% — older plumbing may contain lead solder.
- Estimated remediation: $2,500 per household.
- CDC health risk index: 10.71.
Glendora's Water Providers
Federal drinking water records identify 5 systems in Glendora, CA. The leading 3 providers serve the largest share of residential connections, each operating as a separate entity with its own rate authority, infrastructure management, and EPA compliance obligations — so service conditions are not uniform city-wide.
Overview
We track water quality and home safety data for 2 ZIP codes in Glendora, California (population ~52,326), covering 5 community water systems serving approximately 221,765 people region-wide.
2 of 2 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Glendora: B (83/100)
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
Glendora water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0035 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): 2 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 |
|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | 3 | 2 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 91740 | B | 1 | 0 | Glendora-city, Water Department |
| 91741 | B | 1 | 0 | Glendora-city, Water Department |
All ZIP Codes in Glendora
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.
Glendora Community Health Snapshot
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
What's in Glendora's Water?
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Glendora Infrastructure Age
With 85% 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
Viewed through the lens of construction era, Glendora is predominantly an older city — a median build year of 1966 puts most of the residential inventory in the range where pre-1986 plumbing materials were the standard.
Over half of homes in Glendora 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.
How Remediation Costs Compare in Glendora
Setting Glendora remediation figures against its property market, the resulting ratio sits comfortably in the low tier — a classification that reflects the kind of household financial position where most homeowners can identify documented issues, schedule the work, and absorb the cost without it registering as a significant budget disruption.
Remediation costs in Glendora are relatively low compared to home values. The $1,400–$3,750 estimated range is a small fraction of median property value. Home values are 25% above the California average.
Glendora: Lead Risk & Vulnerable Populations
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.
Practically, the structural drivers in Glendora — 85% pre-rule stock and citywide monitoring at or beyond the regulatory benchmark — make an in-home draw the practical way to translate aggregate averages into the specific conditions at one address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Glendora: Flood History & Water Damage Risk
Flood exposure in Glendora is meaningful by NFIP measures — 9 claims on record and 100% 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.
Glendora has a moderate flood history with 9 FEMA claims averaging $14,980 per payout. 100% 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>$2,500</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 Glendora, CA