The water systems supplying San Marino show a track record of above-average compliance with federal standards - consistently among the better performers in CA.

Data: EPA SDWIS

Overview

We track home safety data for 2 ZIP codes in San Marino, California (population ~12,464), covering 3 community water systems serving approximately 237,591 people region-wide. The EPA snapshots used for this build directly map water systems to 1 of 2 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 San Marino: B (75/100)

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

San Marino water systems draw from: Groundwater, Surface water.

Lead & Copper

• Average lead level (90th percentile): 0.0000 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)

• 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.

Areas with No Violations

All ZIP Codes in San Marino

• 91108 [B]
• 91118

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.

San Marino: Remediation Cost in Perspective

How much of a San Marino home's value does documented remediation represent? A small fraction - the equity share here is in the low tier, and from a household financial perspective, most property owners are considering a commitment that fits comfortably within standard planning rather than a decision that rises to the level of a material budget event or significant equity consideration.

Median Home Value

$2.0M

Est. Remediation

$2,300

Remediation as % of home value 0.1%

Remediation costs in San Marino are relatively low compared to home values. The $1,500–$3,300 estimated range is a small fraction of median property value. Home values are 171% above the California average.

Historical Flood-Claim Evidence for San Marino

3

Total FEMA Flood Claims

0%

A/V Share of Claim-Record ZIPs

Historical NFIP data for San Marino contains 3 flood insurance claims. Among ZIP codes with claim records, 0% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.

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. The <strong>$2,300</strong> remediation estimate shown here excludes flood insurance and is not derived from NFIP claim count.

Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.

Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.