Downey, CA: 4 Violations — 82/100 (2026)
4 ZIP codes · 7 water systems · Updated 2026-06-03
Throughout Downey and across its water systems, EPA compliance data for CA shows above-average performance — violations are minimal, none of the tracked systems have recorded repeated MCL exceedances in recent cycles, and the safety picture has held steady across multiple reporting periods.
How Downey Compares
Data: EPA SDWIS Last verified: 2026-06-03
Downey Water: The Quick Version
- Your city's water systems recorded 4 violations in the past 5 years.
- Average lead level: 0.0019 mg/L.
- Homes built before 1986: 89% — older plumbing may contain lead solder.
- Estimated remediation: $2,225 per household.
- CDC health risk index: 10.71.
Water Systems Serving Downey
Residential water service in Downey, CA is divided among 3 separate utilities, drawn from 7 systems on file with federal regulators.
Overview
We track water quality and home safety data for 4 ZIP codes in Downey, California (population ~111,793), covering 7 community water systems serving approximately 371,400 people region-wide.
4 of 4 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Downey: B (82/100)
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
Downey water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0019 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): 4 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 |
|---|---|---|---|
| Lead | Inorganic | 5 | 4 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 90239 | B | 1 | 0 | Downey - City, Water Department |
| 90240 | B | 1 | 0 | Downey - City, Water Department |
| 90241 | B | 1 | 0 | Downey - City, Water Department |
| 90242 | B | 1 | 0 | Downey - City, Water Department |
All ZIP Codes in Downey
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.
CDC Health Data for Downey
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
Key Contaminants Detected in Downey
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Old Is Downey's Housing Stock?
With 89% 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
While newer cities carry lower aggregate plumbing risk from lead-era construction, Downey sits firmly in the older category. The median build year of 1951 indicates that more than half the housing stock was built before 1986, when lead solder was still legally used in residential copper plumbing — and a substantial portion likely predates 1970, when lead pipes were still commonly installed for service lines. These two thresholds together define the elevated plumbing risk environment that older housing cities carry, independent of what the municipal water supply delivers to the meter.
Over half of homes in Downey 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.
Downey: Remediation Cost in Perspective
When remediation costs are measured against Downey home values, the resulting ratio is in the low tier — addressing documented water and safety issues here claims only a minor fraction of typical equity, and most homeowners are in a position where the financial commitment is straightforward rather than a material burden on their household budget.
Remediation costs in Downey are relatively low compared to home values. The $1,250–$3,475 estimated range is a small fraction of median property value. Home values are 3% above the California average.
Protecting Children from Lead in Downey
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.
Households with kids in the home — for whom CDC guidance places particular weight on minimizing exposure — face a specific local picture in Downey. 89% of homes here come from the pre-rule era, and aggregate utility samples either approach or cross 0.015 mg/L. A baseline draw-test kit and certified lead-removal filtration are available via retailer networks for households confirming conditions at a specific tap.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Downey
Downey's flood exposure sits in the moderate range: 20 NFIP claims on record and 75% of ZIP codes within FEMA-designated flood zones. Residents with private wells or older infrastructure have reasonable grounds to factor flood timing into their water quality awareness.
Downey has a moderate flood history with 20 FEMA claims averaging $62,488 per payout. 75% 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>$2,225</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 Downey, CA