Hamilton County, Ohio
78 ZIP codes · Avg score 64/100 · Grade C · Updated 2026-06-03
The systems supplying Hamilton County's 78 ZIP codes vary in performance — most meet minimum standards, but violations in select areas are on record.
How Hamilton County Compares
How Hamilton County Compares
Hamilton County scores 4 points above the Ohio state average (60/100) and 4 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Hamilton County, Ohio
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 13.2 (asthma 11.4%, diabetes 13.2%)
Estimated additional annual cost per homeowner: $1,354, driven primarily by flood
Infrastructure: 0.388% avg pipe failure probability, 48% of ZIPs at high risk
77.9% of homes built before 1978 (lead paint era)
Violation History (2024–2025)
→ Stable trendEPA violation counts by year across Hamilton County water systems. Health-based shown in red, total in blue.
Peak year: 2025 with 140 violations. Past 5 years: 142 total (142 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
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $1,354
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
385,556 housing units in Hamilton 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 Hamilton County
Remediation costs are relatively manageable for most homeowners in Hamilton 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 Hamilton 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 Hamilton County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | CINCINNATI PUBLIC WATER SYSTEM | 750,200 | 72 |
| 2 | Indian Hill City Public Water System | 15,000 | 70 |
| 3 | Wyoming City Public Water System | 9,700 | 70 |
| 4 | Chateau Estates Mhp Public Water System | 430 | 70 |
| 5 | Honey Creek Village Mhp Public Water System | 225 | 70 |
16 total water systems serve Hamilton County.
All ZIP Codes in Hamilton County
78 ZIP codes tracked in Hamilton County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 45205 | Cincinnati | 70 | B | 1 | $113K |
| 2 | 45206 | Cincinnati | 70 | B | 1 | $270K |
| 3 | 45209 | Cincinnati | 70 | B | 1 | $387K |
| 4 | 45211 | Cincinnati | 70 | B | 1 | $157K |
| 5 | 45213 | Cincinnati | 70 | B | 1 | $259K |
| 6 | 45214 | Cincinnati | 70 | B | 1 | $102K |
| 7 | 45217 | Cincinnati | 70 | B | 1 | $149K |
| 8 | 45224 | Cincinnati | 70 | B | 1 | $174K |
| 9 | 45225 | Cincinnati | 70 | B | 1 | $108K |
| 10 | 45233 | Cincinnati | 70 | B | 1 | $271K |
| 11 | 45240 | Cincinnati | 70 | B | 1 | $177K |
| 12 | 45248 | Cincinnati | 70 | B | 1 | $206K |
| 13 | 45249 | Cincinnati | 70 | B | 1 | $485K |
| 14 | 45251 | Cincinnati | 70 | B | 1 | $176K |
| 15 | 45252 | Cincinnati | 70 | B | 1 | $313K |
| 16 | 45255 | Cincinnati | 70 | B | 1 | $279K |
| 17 | 45201 | Cincinnati | 66 | C | 1 | — |
| 18 | 45207 | Cincinnati | 66 | C | 1 | $192K |
| 19 | 45212 | Cincinnati | 66 | C | 1 | $229K |
| 20 | 45219 | Cincinnati | 66 | C | 1 | $223K |
| 21 | 45221 | Cincinnati | 66 | C | 1 | — |
| 22 | 45229 | Cincinnati | 66 | C | 1 | $316K |
| 23 | 45234 | Cincinnati | 66 | C | 1 | — |
| 24 | 45235 | Cincinnati | 66 | C | 1 | — |
| 25 | 45250 | Cincinnati | 66 | C | 1 | — |
| 26 | 45253 | Cincinnati | 66 | C | 1 | — |
| 27 | 45254 | Cincinnati | 66 | C | 1 | — |
| 28 | 45258 | Cincinnati | 66 | C | 1 | — |
| 29 | 45262 | Cincinnati | 66 | C | 1 | — |
| 30 | 45263 | Cincinnati | 66 | C | 1 | — |
| 31 | 45264 | Cincinnati | 66 | C | 1 | — |
| 32 | 45267 | Cincinnati | 66 | C | 1 | — |
| 33 | 45268 | Cincinnati | 66 | C | 1 | — |
| 34 | 45269 | Cincinnati | 66 | C | 1 | — |
| 35 | 45270 | Cincinnati | 66 | C | 1 | — |
| 36 | 45271 | Cincinnati | 66 | C | 1 | — |
| 37 | 45273 | Cincinnati | 66 | C | 1 | — |
| 38 | 45274 | Cincinnati | 66 | C | 1 | — |
| 39 | 45275 | Cincinnati | 66 | C | 1 | — |
| 40 | 45277 | Cincinnati | 66 | C | 1 | — |
| 41 | 45280 | Cincinnati | 66 | C | 1 | — |
| 42 | 45296 | Cincinnati | 66 | C | 1 | — |
| 43 | 45298 | Cincinnati | 66 | C | 1 | — |
| 44 | 45299 | Cincinnati | 66 | C | 1 | — |
| 45 | 45999 | Cincinnati | 66 | C | 1 | — |
| 46 | 45203 | Cincinnati | 65 | C | 1 | $296K |
| 47 | 45204 | Cincinnati | 65 | C | 1 | $93K |
| 48 | 45208 | Cincinnati | 65 | C | 1 | $491K |
| 49 | 45215 | Cincinnati | 65 | C | 1 | $200K |
| 50 | 45216 | Cincinnati | 65 | C | 1 | $138K |
| 51 | 45218 | Cincinnati | 65 | C | 1 | $170K |
| 52 | 45220 | Cincinnati | 65 | C | 1 | $385K |
| 53 | 45222 | Cincinnati | 65 | C | 1 | — |
| 54 | 45232 | Cincinnati | 65 | C | 1 | $123K |
| 55 | 45236 | Cincinnati | 65 | C | 1 | $219K |
| 56 | 45238 | Cincinnati | 65 | C | 1 | $169K |
| 57 | 45242 | Cincinnati | 65 | C | 1 | $421K |
| 58 | 45243 | Cincinnati | 65 | C | 1 | $617K |
| 59 | 45246 | Cincinnati | 65 | C | 1 | $190K |
| 60 | 45247 | Cincinnati | 65 | C | 1 | $268K |
| 61 | 45001 | Addyston | 61 | C | 2 (1 health) | $122K |
| 62 | 45202 | Cincinnati | 60 | C | 1 | $444K |
| 63 | 45223 | Cincinnati | 60 | C | 1 | $204K |
| 64 | 45227 | Cincinnati | 60 | C | 1 | $256K |
| 65 | 45230 | Cincinnati | 60 | C | 1 | $237K |
| 66 | 45231 | Cincinnati | 60 | C | 1 | $165K |
| 67 | 45237 | Cincinnati | 60 | C | 1 | $159K |
| 68 | 45239 | Cincinnati | 60 | C | 1 | $156K |
| 69 | 45241 | Cincinnati | 60 | C | 1 | $292K |
| 70 | 45244 | Cincinnati | 60 | C | 1 | $346K |
| 71 | 45002 | Cleves | 58 | C | 1 | $281K |
| 72 | 45030 | Harrison | 58 | C | 1 | $235K |
| 73 | 45226 | Cincinnati | 55 | C | 1 | $387K |
| 74 | 45052 | North Bend | 53 | D | 0 | $284K |
| 75 | 45053 | Okeana | 53 | D | 0 | $323K |
| 76 | 45063 | Shandon | 53 | D | 0 | — |
| 77 | 45033 | Hooven | 40 | D | 0 | $81K |
| 78 | 45041 | Miamitown | 40 | D | 0 | — |
Recommended Buyer Guides for Hamilton 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 — 77.9% of homes built before 1978
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
- Best Sump Pumps — Flood is the top compound risk factor
- Best Mold Test Kits — Flood-driven moisture and mold risk
Deep Dive Reports
Detailed analysis for Hamilton County, Ohio
Overview
Hamilton County in Ohio covers 78 ZIP codes with an average Home Safety Score of C (64/100).
73 of 78 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.