Washington County, Maryland
20 ZIP codes · Avg score 57/100 · Grade C · Updated 2026-06-03
Although much of Washington County meets baseline standards, some of its 20 ZIP codes show violations that merit closer attention.
How Washington County Compares
How Washington County Compares
Washington County scores 4 points below the Maryland state average (61/100) and 11 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Washington County, Maryland
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 14.2 (asthma 10.7%, diabetes 13.3%)
Estimated additional annual cost per homeowner: $2,376, driven primarily by sea_level
Infrastructure: 0.357% avg pipe failure probability, 16% of ZIPs at high risk
61.8% of homes built before 1978 (lead paint era)
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: $2,376
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
63,025 housing units in Washington 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 Washington County
Remediation costs are relatively manageable for most homeowners in Washington 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 Washington 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 Washington County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | CITY OF HAGERSTOWN | 92,200 | 19 |
| 2 | Mount Aetna | 688 | 12 |
| 3 | TOWN OF WILLIAMSPORT DISTRIBUTION SYSTEM | 2,400 | 7 |
| 4 | Lakeside Village | 1,575 | 7 |
| 5 | Saint James School | 200 | 7 |
19 total water systems serve Washington County.
All ZIP Codes in Washington County
20 ZIP codes tracked in Washington County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 21783 | Smithsburg | 70 | B | 1 | $330K |
| 2 | 21713 | Boonsboro | 69 | C | 5 (1 health) | $348K |
| 3 | 21741 | Hagerstown | 68 | C | 1 | — |
| 4 | 21782 | Sharpsburg | 65 | C | 0 | $296K |
| 5 | 21746 | Hagerstown | 64 | C | 1 | — |
| 6 | 21747 | Hagerstown | 64 | C | 1 | — |
| 7 | 21748 | Hagerstown | 64 | C | 1 | — |
| 8 | 21749 | Hagerstown | 64 | C | 1 | — |
| 9 | 21740 | Hagerstown | 63 | C | 1 | $242K |
| 10 | 21750 | Hancock | 63 | C | 2 | $213K |
| 11 | 21795 | Williamsport | 59 | C | 6 (1 health) | $276K |
| 12 | 21742 | Hagerstown | 58 | C | 1 | $280K |
| 13 | 21734 | Funkstown | 57 | C | 0 | $242K |
| 14 | 21711 | Big Pool | 53 | D | 0 | $274K |
| 15 | 21720 | Cavetown | 53 | D | 0 | — |
| 16 | 21756 | Keedysville | 53 | D | 0 | $361K |
| 17 | 21722 | Clear Spring | 45 | D | 0 | $298K |
| 18 | 21766 | Little Orleans | 40 | D | 0 | $192K |
| 19 | 21779 | Rohrersville | 40 | D | 0 | $551K |
| 20 | 21719 | Cascade | 32 | F | 2 (1 health) | $231K |
Recommended Buyer Guides for Washington County
Where county records show a lead exceedance or pre-1978 housing concentration, lead-specific filters and test kits move toward the top of the list.
- Best Water Filters for Lead — Lead above EPA action level in 1 ZIP code
- Best Lead Paint Test Kits — 61.8% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Deep Dive Reports
Detailed analysis for Washington County, Maryland
Overview
Washington County in Maryland covers 20 ZIP codes with an average Home Safety Score of C (57/100).
12 of 20 ZIP codes have recorded EPA violations. 3 health-based violations have been documented.
← Back to Maryland 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.