Monterey County, California
36 ZIP codes · Avg score 71/100 · Grade B · Updated 2026-06-03
Covering 36 ZIP codes, Monterey County earns a high grade for tap water — most systems report zero health-based violations, and the overall compliance rate comfortably exceeds federal benchmarks.
How Monterey County Compares
How Monterey County Compares
Monterey County scores 2 points below the California state average (73/100) and 3 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Monterey County, California
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 11.6 (asthma 9.6%, diabetes 12.5%)
Estimated additional annual cost per homeowner: $2,686, driven primarily by wildfire
Infrastructure: 0.377% avg pipe failure probability, 25% of ZIPs at high risk
68.7% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
↓ Improving trendEPA violation counts by year across Monterey County water systems. Health-based shown in red, total in blue.
Peak year: 2022 with 42 violations. Past 5 years: 110 total (110 health-based). Health-based violations are declining versus the prior 2-year window.
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
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $2,686
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
143,377 housing units in Monterey 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 Monterey County
Remediation costs are relatively manageable for most homeowners in Monterey 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 Monterey County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Monterey County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Csp-pfeiffer Big Sur | 585 | 48 |
| 2 | Merrill Gardens Iris Canyon Ws | 161 | 48 |
| 3 | The Willows Resort | 57 | 48 |
| 4 | Cal Am Water Company - Monterey | 92,450 | 41 |
| 5 | City of Gonzales, | 8,327 | 29 |
68 total water systems serve Monterey County.
All ZIP Codes in Monterey County
36 ZIP codes tracked in Monterey County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 93922 | Carmel | 83 | B | 1 | — |
| 2 | 93950 | Pacific Grove | 83 | B | 0 | $1129K |
| 3 | 93955 | Seaside | 83 | B | 0 | $694K |
| 4 | 95004 | Aromas | 83 | B | 0 | $914K |
| 5 | 93932 | Lockwood | 81 | B | 1 | $550K |
| 6 | 93960 | Soledad | 81 | B | 2 | $568K |
| 7 | 95039 | Moss Landing | 81 | B | 1 | $441K |
| 8 | 93450 | San Ardo | 78 | B | 2 (1 health) | $427K |
| 9 | 93912 | Salinas | 78 | B | 3 | — |
| 10 | 93915 | Salinas | 78 | B | 3 | — |
| 11 | 93954 | San Lucas | 78 | B | 3 (1 health) | $303K |
| 12 | 93920 | Big Sur | 76 | B | 1 | $1804K |
| 13 | 93901 | Salinas | 74 | B | 3 | $721K |
| 14 | 93902 | Salinas | 74 | B | 3 | — |
| 15 | 93905 | Salinas | 74 | B | 3 | $570K |
| 16 | 93906 | Salinas | 74 | B | 3 | $595K |
| 17 | 93907 | Salinas | 74 | B | 3 | $677K |
| 18 | 93908 | Salinas | 74 | B | 3 | $1071K |
| 19 | 93930 | King City | 73 | B | 0 | $404K |
| 20 | 93942 | Monterey | 73 | B | 12 (2 health) | — |
| 21 | 93943 | Monterey | 73 | B | 12 (2 health) | — |
| 22 | 93944 | Monterey | 73 | B | 12 (2 health) | — |
| 23 | 93451 | San Miguel | 72 | B | 0 | $582K |
| 24 | 93933 | Marina | 72 | B | 0 | $777K |
| 25 | 93940 | Monterey | 70 | B | 12 (2 health) | $1040K |
| 26 | 93426 | Bradley | 69 | C | 10 (5 health) | $472K |
| 27 | 93923 | Carmel | 68 | C | 1 | $1571K |
| 28 | 93924 | Carmel Valley | 66 | C | 1 | $1133K |
| 29 | 93927 | Greenfield | 66 | C | 5 (1 health) | $464K |
| 30 | 93925 | Chualar | 64 | C | 2 (1 health) | $656K |
| 31 | 93921 | Carmel By The Sea | 55 | C | 0 | $2000K |
| 32 | 93953 | Pebble Beach | 55 | C | 0 | $1797K |
| 33 | 93926 | Gonzales | 53 | D | 22 (17 health) | $598K |
| 34 | 93928 | Jolon | 53 | D | 0 | — |
| 35 | 93962 | Spreckels | 53 | D | 0 | $830K |
| 36 | 95012 | Castroville | 53 | D | 22 (21 health) | $630K |
Recommended Buyer Guides for Monterey County
Filtered against EPA monitoring data and CDC lead-exposure guidance, the guides below skip the generic catalog and connect directly to the contaminants and hazards on file here.
- Best Lead Paint Test Kits — 68.7% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best HEPA Air Purifiers for Wildfire Smoke — Wildfire is the top compound risk factor
Deep Dive Reports
Detailed analysis for Monterey County, California
Overview
Monterey County in California covers 36 ZIP codes with an average Home Safety Score of B (71/100).
26 of 36 ZIP codes have recorded EPA violations. 55 health-based violations have been documented.
← Back to California water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.