Duarte, CA Water Safety: 60/100 (2026)
3 ZIP codes · 4 water systems · Updated 2026-06-03
Water monitoring across Duarte paints a mid-range picture within CA — solid compliance in some service zones, documented concerns in others. Most violations on record are concentrated in specific areas, and the overall grade has held in the middle tier without major shifts in recent monitoring cycles.
How Duarte Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Duarte Water
- Homes built before 1986: 72% — older plumbing may contain lead solder.
- Estimated remediation: $1,600 per household.
- CDC health risk index: 10.71.
Who Supplies Your Water in Duarte
Duarte, CA is covered by 3 major water utilities out of 4 federally tracked systems, each managing its own pipes, treatment processes, and EPA filings. What a household gets from the tap depends on which provider's system serves that address.
Overview
We track water quality and home safety data for 3 ZIP codes in Duarte, California (population ~27,999), covering 4 community water systems serving approximately 199,820 people region-wide.
No EPA violations recorded across any ZIP codes in Duarte — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Duarte: C (60/100)
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
Duarte water systems draw from: Groundwater.
Lead & Copper
- Lead data: not yet available for Duarte
- 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): 3 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 91008 | C | Cal-am Water Company - Duarte | 24,773 |
| 91009 | D | MONROVIA-CITY, WATER DEPT. | 37,931 |
| 91010 | C | Azusa Light and Water | 110,044 |
All ZIP Codes in Duarte
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 Duarte
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
Housing & Infrastructure in Duarte
With 72% 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
When more than half a city's housing predates the 1986 federal ban on lead solder, plumbing-era lead risk becomes a citywide concern rather than an exception. Duarte's median build year of 1969 places it squarely in that category.
Over half of homes in Duarte 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 Duarte Homeowners
Equity impact data for Duarte lands in the favorable tier — remediation claims a small slice of what properties here are worth.
Remediation costs in Duarte are relatively low compared to home values. The $800–$2,533 estimated range is a small fraction of median property value. Home values are 131% above the California average.
Lead Exposure Risk for Children in Duarte
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.
Routinely in Duarte, where 72% of housing predates the solder ban and aggregate utility readings hover near the federal threshold, a faucet-level draw functions as a standard household step for families with small kids.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Duarte
Flood zone coverage in Duarte is limited, and NFIP data confirms that pattern with a modest claim total. Limited flood frequency generally means limited risk of the water-quality disruptions that large flood events can trigger.
Duarte has a relatively low flood history with 11 FEMA claims on record. While risk is limited, severe weather events can still impact water infrastructure.
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.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Duarte
- 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. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 72% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Duarte, CA