Williams County, Ohio
9 ZIP codes · Avg score 71/100 · Grade B · Updated 2026-06-03
For households in Williams County, the 9 ZIP codes on record show consistently safe tap water.
How Williams County Compares
How Williams County Compares
Williams County scores 11 points above the Ohio state average (60/100) and 3 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Williams County, Ohio
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 15.3 (asthma 11.1%, diabetes 14.4%)
Estimated additional annual cost per homeowner: $1,462, driven primarily by energy_code_gap
Infrastructure: 0.442% avg pipe failure probability, 67% of ZIPs at high risk
79.4% 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: $1,462
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
16,026 housing units in Williams 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 Williams County
Remediation costs are relatively manageable for most homeowners in Williams 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 Williams 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 Williams County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Williams Company/hillside Country Living | 225 | 4 |
| 2 | West Unity Village | 1,760 | 4 |
| 3 | PIONEER VILLAGE | 1,380 | 2 |
| 4 | Aqua Ohio - Seneca | 750 | 2 |
| 5 | Bryan City | 8,729 | 2 |
9 total water systems serve Williams County.
All ZIP Codes in Williams County
9 ZIP codes tracked in Williams County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 43517 | Edgerton | 83 | B | 1 | $127K |
| 2 | 43554 | Pioneer | 83 | B | 0 | $147K |
| 3 | 43570 | West Unity | 83 | B | 0 | $117K |
| 4 | 43518 | Edon | 81 | B | 1 | $144K |
| 5 | 43543 | Montpelier | 77 | B | 2 (1 health) | $130K |
| 6 | 43506 | Bryan | 76 | B | 2 | $155K |
| 7 | 43501 | Alvordton | 53 | D | 0 | $125K |
| 8 | 43505 | Blakeslee | 53 | D | 0 | $216K |
| 9 | 43531 | Kunkle | 53 | D | 0 | $38K |
Recommended Buyer Guides for Williams County
Eight risk categories drive the selection — PFAS exceedance, lead above EPA action level, pre-1978 housing share, EPA Radon Zone 1, flood-top-risk, wildfire-top-risk, multi-contaminant load, and a baseline fallback — and each category maps to a specific buyer-guide track that surfaces when the county data hits its threshold for that hazard signal.
- Best Lead Paint Test Kits — 79.4% of homes built before 1978
Deep Dive Reports
Detailed analysis for Williams County, Ohio
Overview
Williams County in Ohio covers 9 ZIP codes with an average Home Safety Score of B (71/100).
4 of 9 ZIP codes have recorded EPA violations. 1 health-based violation have been documented.
← Back to Ohio 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.