The systems supplying Montclair vary in performance across CA benchmarks - most meet minimum federal standards, but documented violations in select areas are on record.

Data: EPA SDWIS

Overview

We track home safety data for 1 ZIP code in Montclair, California (population ~37,515), covering 2 community water systems serving approximately 241,027 people region-wide. The EPA snapshots used for this build directly map water systems to 1 of 1 ZIP codes.

The available EPA record reports 0 violations for 1 ZIP code with a reported violation count.

Home Safety Score

Average Home Safety Score for Montclair: C (58/100)

Model 4.0.0 uses four measured components across three equally weighted domains. If a required domain is unavailable, no score is published:

Factor	What It Measures
Water Quality	EPA violations and compliance history
PFAS MCL Screen	UCMR 5 testing against the covered federal MCLs
Radon Risk	EPA radon zone classification
Annual AQI	EPA AirData county-year median with at least 90 observed days

Water Sources

Montclair water systems draw from: Surface water.

Lead & Copper

• Average lead level (90th percentile): 0.0006 mg/L (EPA action level: 0.015 mg/L)
• 0 of 1 ZIP code with known status exceed the EPA lead action level

Radon Risk

Dominant radon zone: Zone 2 (Moderate Risk)

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

Areas with No Violations

All ZIP Codes in Montclair

• 91763 [C]

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

Reporting periods vary by source. Missing data is shown as unavailable, not as zero.

Housing Age Profile

Heavily weighted toward older construction, Montclair's housing stock carries a median build year of 1961. That profile puts a majority of homes in the era when lead-soldered copper plumbing was standard practice.

1961

Median Year Built

74%

Pre-1986 (Lead Paint Risk)

31%

Pre-1970 (Lead Pipes Risk)

Pre-1970 (31%) 1970–1986 (43%) Post-1986 (26%)

Over half of homes in Montclair 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 Montclair Homeowners

At current valuations, Montclair sits in the low remediation-share tier - the equity impact of fixing documented issues is proportionally minor.

Median Home Value

$550,000

Est. Remediation

$1,000

Remediation as % of home value 0.2%

Remediation costs in Montclair are relatively low compared to home values. The $400–$1,600 estimated range is a small fraction of median property value. Home values are 26% below the California average.

Lead Exposure Risk for Children in Montclair

74%

Homes Built Before 1986

0.0006

mg/L Avg Lead (Limit: 0.015)

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.

When older housing represents 74% of the local inventory or aggregate readings approach the federal action level, an in-home check becomes the standard way to translate citywide averages into the specific reality of an individual Montclair address.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.