St. Mary's County, Maryland
28 ZIP codes · Home Safety Score unavailable · 0 of 28 tracked ZIP records scored
Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData
ZIP Code Risk Map
Water Quality Map: St. Mary's County, Maryland
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 12.5 (asthma 10.7%, diabetes 11.4%)
Modeled additional annual cost estimate per homeowner: $2,759, largest modeled factor: Sea Level
30% of homes built before 1980 (lead paint was banned for residential use in 1978)
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 DWINSA infrastructure needs, EPA SDWIS violations, and EPA lead indicators.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $2,759
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
45,306 housing units in St. Mary's 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 St. Mary's County
Modeled remediation costs in St. Mary's County can be compared with the median property value; actual costs vary by property.
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 St. Mary's County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems mapped to St. Mary's County ZIP codes
8 community water systems mapped to St. Mary's County ZIP codes; EPA may list more systems serving the county.
Show all 8 water systems
19 water systems mapped to St. Mary's County ZIP codes in our data; EPA may list more systems serving the county.
Systems with the most violations in St. Mary's County
5 water systems with violations in EPA records.
All ZIP Codes in St. Mary's County
28 ZIP codes tracked in St. Mary's County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 20606 | Abell | — | — | $464K | |
| 2 | 20609 | Avenue | — | — | $475K | |
| 3 | 20618 | Bushwood | — | — | $292K | |
| 4 | 20619 | California | — | — | 12 (1 health) | $364K |
| 5 | 20620 | Callaway | — | — | 1 | $369K |
| 6 | 20621 | Chaptico | — | — | 4 | $563K |
| 7 | 20624 | Clements | — | — | 3 | $424K |
| 8 | 20626 | Coltons Point | — | — | — | |
| 9 | 20627 | Compton | — | — | — | |
| 10 | 20628 | Dameron | — | — | $412K | |
| 11 | 20630 | Drayden | — | — | 1 | $585K |
| 12 | 20634 | Great Mills | — | — | 9 (1 health) | $335K |
| 13 | 20635 | Helen | — | — | — | |
| 14 | 20636 | Hollywood | — | — | 11 | $470K |
| 15 | 20650 | Leonardtown | — | — | 13 | $464K |
| 16 | 20653 | Lexington Park | — | — | 19 (3 health) | $342K |
| 17 | 20656 | Loveville | — | — | 2 | — |
| 18 | 20659 | Mechanicsville | — | — | 11 | $388K |
| 19 | 20660 | Morganza | — | — | — | |
| 20 | 20667 | Park Hall | — | — | 5 | — |
| 21 | 20670 | Patuxent River | — | — | 7 | — |
| 22 | 20674 | Piney Point | — | — | $399K | |
| 23 | 20680 | Ridge | — | — | $392K | |
| 24 | 20684 | Saint Inigoes | — | — | $376K | |
| 25 | 20686 | Saint Marys City | — | — | — | |
| 26 | 20687 | Scotland | — | — | $772K | |
| 27 | 20690 | Tall Timbers | — | — | $559K | |
| 28 | 20692 | Valley Lee | — | — | 2 | $382K |
Recommended Buyer Guides for St. Mary's County
Selection follows a fixed set of rules applied to local records: signals such as PFAS detections, lead action-level exceedances on record, a large share of pre-1978 housing, EPA Radon Zone 1, or a top flood or wildfire risk each add a related guide, and when none applies, general water testing and filtration guides are shown instead.
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
Deep Dive Reports
Detailed analysis for St. Mary's County, Maryland
Overview
St. Mary's County in Maryland covers 28 tracked ZIP records. No Home Safety Score is published because the required model evidence is incomplete for every tracked record; missing evidence is not treated as zero.
14 of 14 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. 3 health-based violations appear in the available health breakdown.
← Back to Maryland 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.