Marin County, California
42 ZIP codes · Avg score 100/100 · Grade A · Updated
ZipCheckup grade for Marin County: A.
No federal data flags a major home-safety concern for this ZIP.
Marin County - 42 ZIP codes, above-average safety grade.
How Marin County Compares
How Marin County Compares
Marin County scores 24 points above the California state average (76/100) and 27 points above the national average (73/100).
Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData Last verified:
ZIP Code Risk Map
Water Quality Map: Marin County, California
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 10.8 (asthma 9.4%, diabetes 10.2%)
Estimated additional annual cost per homeowner: $3,981, driven primarily by sea_level
82.3% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
→ Stable trendEPA violation counts by year across Marin County water systems. Health-based shown in red, total in blue.
Peak year: 2021 with 8 violations. Past 5 years: 23 total (23 health-based).
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Modeled area-level indicator, not a failure probability. Sources: Census ACS housing age, EPA DWINS infrastructure needs, EPA SDWIS violations, and EPA lead indicators.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $3,981
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
111,551 housing units in Marin County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Marin County
Remediation costs are relatively manageable for most homeowners in Marin County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Marin County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Marin County
7 community water systems serving Marin County.
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Show all 7 water systems
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Systems with the most violations in Marin County
2 water systems with recorded EPA violations.
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All ZIP Codes in Marin County
42 ZIP codes tracked in Marin County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 94901 | San Rafael | 100 | A | 0 | $1370K |
| 2 | 94903 | San Rafael | 100 | A | 0 | $1149K |
| 3 | 94904 | Greenbrae | 100 | A | 0 | $2000K |
| 4 | 94920 | Belvedere Tiburon | 100 | A | 0 | $2000K |
| 5 | 94924 | Bolinas | 100 | A | 1 | $2000K |
| 6 | 94925 | Corte Madera | 100 | A | 0 | $1702K |
| 7 | 94930 | Fairfax | 100 | A | 0 | $1152K |
| 8 | 94933 | Forest Knolls | 100 | A | 0 | $886K |
| 9 | 94937 | Inverness | 100 | A | 0 | $1537K |
| 10 | 94938 | Lagunitas | 100 | A | 0 | $1005K |
| 11 | 94939 | Larkspur | 100 | A | 0 | $2000K |
| 12 | 94941 | Mill Valley | 100 | A | 0 | $1990K |
| 13 | 94945 | Novato | 100 | A | 0 | $1094K |
| 14 | 94946 | Nicasio | 100 | A | 0 | $2000K |
| 15 | 94947 | Novato | 100 | A | 0 | $995K |
| 16 | 94949 | Novato | 100 | A | 0 | $1076K |
| 17 | 94957 | Ross | 100 | A | 0 | $2000K |
| 18 | 94960 | San Anselmo | 100 | A | 0 | $1589K |
| 19 | 94963 | San Geronimo | 100 | A | 0 | $1221K |
| 20 | 94964 | San Quentin | 100 | A | 0 | — |
| 21 | 94965 | Sausalito | 100 | A | 0 | $1493K |
| 22 | 94973 | Woodacre | 100 | A | 0 | $1111K |
| 23 | 94912 | San Rafael | — | — | — | |
| 24 | 94913 | San Rafael | — | — | — | |
| 25 | 94914 | Kentfield | — | — | — | |
| 26 | 94915 | San Rafael | — | — | — | |
| 27 | 94929 | Dillon Beach | — | — | $1564K | |
| 28 | 94940 | Marshall | — | — | 0 | — |
| 29 | 94942 | Mill Valley | — | — | — | |
| 30 | 94948 | Novato | — | — | — | |
| 31 | 94950 | Olema | — | — | — | |
| 32 | 94956 | Point Reyes Station | — | — | 0 | $2000K |
| 33 | 94966 | Sausalito | — | — | — | |
| 34 | 94970 | Stinson Beach | — | — | 1 | $1458K |
| 35 | 94971 | Tomales | — | — | 0 | $880K |
| 36 | 94974 | San Quentin | — | — | — | |
| 37 | 94976 | Corte Madera | — | — | — | |
| 38 | 94977 | Larkspur | — | — | — | |
| 39 | 94978 | Fairfax | — | — | — | |
| 40 | 94979 | San Anselmo | — | — | — | |
| 41 | 94998 | Novato | — | — | — | |
| 42 | 95950 | Grimes | — | — | 2 | — |
Recommended Buyer Guides for Marin County
While many sites publish identical guide lists across every county they cover, the selection here changes by location - driven by the EPA, NSF, FEMA, and CDC datasets that describe the actual conditions documented for this jurisdiction in the federal record.
- Best Lead Paint Test Kits — 82.3% of homes built before 1978
Deep Dive Reports
Detailed analysis for Marin County, California
Overview
Marin County in California covers 42 tracked ZIP records with an average Home Safety Score of A (100/100) across 22 scored records.
3 of 27 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. The available record reports no health-based violations for this measured scope.
← Back to California Home Safety Profile
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- PFAS screening: EPA UCMR 5
- Radon zones: EPA Map of Radon Zones
- Air quality: EPA AirData annual AQI
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Reporting periods vary by source. Missing data is shown as unavailable, not as zero.