In current CA EPA data, San Anselmo's tap water sits in the high-safety tier.

Data: EPA SDWIS

Overview

We track home safety data for 2 ZIP codes in San Anselmo, California (population ~15,891), covering 1 community water system serving approximately 186,895 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 Anselmo: A (100/100)

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 Anselmo water systems draw from: 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 3 (Low Risk)

• Zone 1 (High): 0 ZIP codes
• Zone 2 (Moderate): 0 ZIP codes
• Zone 3 (Low): 2 ZIP codes

Areas with No Violations

All ZIP Codes in San Anselmo

• 94960 [A]
• 94979

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 Anselmo: Remediation Cost in Perspective

In San Anselmo, the equity impact of remediation is proportionally small - not the kind of financial commitment that rises to the level of a genuine planning constraint, but a minor share of what most properties here are worth.

Median Home Value

$1.6M

Est. Remediation

$1,500

Remediation as % of home value 0.1%

Remediation costs in San Anselmo are relatively low compared to home values. The $1,000–$2,150 estimated range is a small fraction of median property value. Home values are 115% above the California average.

Historical Flood-Claim Evidence for San Anselmo

317

Total FEMA Flood Claims

$50,564

Avg Reported Sum With Payment Data

100%

A/V Share of Claim-Record ZIPs

Historical NFIP data for San Anselmo contains 317 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $50,564. Among ZIP codes with claim records, 100% 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>$1,500</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.