Compared to top-scoring cities in OH, Cincinnati lands in the middle tier - some water systems meet standards cleanly, others carry documented violations, and performance can vary significantly across service areas.

Data: EPA SDWIS, FEMA NFIP, Census ACS Last verified: 2026-07-19

Water Quality in Cincinnati

We track water quality and home safety data for 71 ZIP codes in Cincinnati, Ohio, covering 12 community water systems serving approximately 814,555 people.

71 of 71 ZIP codes (100%) have recorded EPA violations - 71 total, including no health-based violations.

Average Home Safety Score: C (66/100)

Water sources: Groundwater, Surface water.

Top Contaminants

Lead Risk

• Average lead level (90th percentile): 0.0020 mg/L
• 79% of housing built before 1986 (when lead solder was banned)
• 35% of housing built before 1950 (when lead pipes were standard)
• Median year built: 1951
• Most common estimated pipe material: Galvanized Steel or Copper
• Lead exposure risk score: 61/100
• Estimated lead service line probability: 24%
• 44 ZIP codes classified as high or very high lead risk

With 79% of homes built before the 1986 lead solder ban, Cincinnati residents - especially those in older neighborhoods - should consider testing their tap water for lead. Homes built before 1950 are at the highest risk of having lead service lines.

Housing Age Distribution

376,596 total housing units across 71 ZIP codes:

Flood Risk

FEMA National Flood Insurance Program data for Cincinnati:

• 1,659 flood insurance claims on record
• $31,718,384 total paid out
• $19,119 average claim payout
• Dominant FEMA flood zone: AE (High risk)
• 23 of 71 ZIP codes in high-risk flood zones (A/V)

Radon Risk

Dominant EPA radon zone: Zone 1 (High Risk)

• Zone 1 (High): 70 ZIP codes
• Zone 2 (Moderate): 1 ZIP codes
• Zone 3 (Low): 0 ZIP codes

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

Neighborhoods by Safety Score

Safest Areas

Areas Needing Attention

What Cincinnati Residents Can Do

Test Your Water

• Order a certified lab test - home test kits cost $20–50 and cover lead, bacteria, and common contaminants
• Request your utility's CCR (Consumer Confidence Report) - your water provider must publish this annually
• Check your ZIP code - each area in Cincinnati has different water systems and risk levels

Filter Your Water

• NSF-certified pitcher filter removes chlorine taste and some contaminants ($20–40)
• NSF 53-certified filter for lead - recommended for homes built before 1986
• Reverse osmosis system removes 95%+ of contaminants including lead, PFAS, and nitrates ($150–400)

Test for Radon

• Cincinnati is in a high-risk radon area
• Short-term radon test kits cost $10–25
• If levels exceed 4 pCi/L, EPA recommends professional mitigation

Stay Informed

• Visit your ZIP code report for detailed, address-level data
• Sign up for EPA water quality alerts
• Review the annual water quality report from your local utility

All ZIP Codes in Cincinnati

• 45201 [C] - 1 violation
• 45202 [C] - 1 violation
• 45203 [C] - 1 violation
• 45204 [C] - 1 violation
• 45205 [B] - 1 violation
• 45206 [B] - 1 violation
• 45207 [C] - 1 violation
• 45208 [C] - 1 violation
• 45209 [B] - 1 violation
• 45211 [B] - 1 violation
• 45212 [C] - 1 violation
• 45213 [B] - 1 violation
• 45214 [B] - 1 violation
• 45215 [C] - 1 violation
• 45216 [C] - 1 violation
• 45217 [B] - 1 violation
• 45218 [C] - 1 violation
• 45219 [C] - 1 violation
• 45220 [C] - 1 violation
• 45221 [C] - 1 violation
• 45222 [C] - 1 violation
• 45223 [C] - 1 violation
• 45224 [B] - 1 violation
• 45225 [B] - 1 violation
• 45226 [C] - 1 violation
• 45227 [C] - 1 violation
• 45229 [C] - 1 violation
• 45230 [C] - 1 violation
• 45231 [C] - 1 violation
• 45232 [C] - 1 violation
• 45233 [B] - 1 violation
• 45234 [C] - 1 violation
• 45235 [C] - 1 violation
• 45236 [C] - 1 violation
• 45237 [C] - 1 violation
• 45238 [C] - 1 violation
• 45239 [C] - 1 violation
• 45240 [B] - 1 violation
• 45241 [C] - 1 violation
• 45242 [C] - 1 violation
• 45243 [C] - 1 violation
• 45244 [C] - 1 violation
• 45245 [B] - 1 violation
• 45246 [C] - 1 violation
• 45247 [C] - 1 violation
• 45248 [B] - 1 violation
• 45249 [B] - 1 violation
• 45250 [C] - 1 violation
• 45251 [B] - 1 violation
• 45252 [B] - 1 violation
• 45253 [C] - 1 violation
• 45254 [C] - 1 violation
• 45255 [B] - 1 violation
• 45258 [C] - 1 violation
• 45262 [C] - 1 violation
• 45263 [C] - 1 violation
• 45264 [C] - 1 violation
• 45267 [C] - 1 violation
• 45268 [C] - 1 violation
• 45269 [C] - 1 violation
• 45270 [C] - 1 violation
• 45271 [C] - 1 violation
• 45273 [C] - 1 violation
• 45274 [C] - 1 violation
• 45275 [C] - 1 violation
• 45277 [C] - 1 violation
• 45280 [C] - 1 violation
• 45296 [C] - 1 violation
• 45298 [C] - 1 violation
• 45299 [C] - 1 violation
• 45999 [C] - 1 violation

Frequently Asked Questions

Is the tap water safe to drink in Cincinnati, OH?

Cincinnati has an average Home Safety Score of 66/100 (grade C) across 71 ZIP codes. There are 71 recorded EPA violations, 0 of which are health-based. Safety varies by neighborhood - check your specific ZIP code report for details.

Does Cincinnati have lead in the water?

The average 90th-percentile lead level across Cincinnati is 0.0020 mg/L, below the EPA action level of 0.015 mg/L. No ZIP codes currently exceed the EPA lead action level. About 79% of housing was built before 1986, when lead solder was banned.

Is Cincinnati at risk for flooding?

FEMA data shows 1,659 flood insurance claims in Cincinnati ZIP codes, with an average payout of $19,119. 23 of 71 ZIP codes are in high-risk FEMA flood zones (A or V).

Are there lead pipes in Cincinnati homes?

79% of Cincinnati housing was built before 1986, when lead solder was common in plumbing. 35% was built before 1950, when lead pipes were standard. The most common estimated pipe material is Galvanized Steel or Copper. The estimated probability of lead service lines is 24%. We recommend testing your water if your home was built before 1986.

What contaminants have been found in Cincinnati water?

The most common contaminants by violation count are Surface Water Treatment Rule. Across 71 ZIP codes, 71 have recorded EPA violations. Check your ZIP code report for the specific contaminants in your area.

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Housing age: U.S. Census Bureau American Community Survey
• Flood data: FEMA National Flood Insurance Program
• Lead exposure: Composite risk score based on housing age, water lead levels, and service line estimates
• Radon: EPA Map of Radon Zones

Updated daily.

Housing Age Profile

Housing age matters for water quality because lead solder was widely used in plumbing until the 1986 federal ban. Cincinnati's median build year of 1951 suggests a majority of homes were constructed under the newer standard - a meaningful factor when assessing household-level lead risk from tap water.

1951

Median Year Built

0%

Pre-1986 (Lead Paint Risk)

0%

Pre-1970 (Lead Pipes Risk)

Most homes in Cincinnati were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.

Source: U.S. Census Bureau ACS B25034.

Lead Exposure Risk for Children in Cincinnati

0.002

mg/L Avg Lead (Limit: 0.015)

Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.

Lead risk in Cincinnati appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.

Flood & Climate Risk in Cincinnati

Across the NFIP's long tracking period, Cincinnati shows 1659 claims and 0% of ZIP codes within FEMA-designated flood zones - figures that place it in moderate flood exposure territory. At this level, the water-quality implications of flooding - contaminated wells, stressed treatment intake, distribution backflow - move from theoretical edge cases to genuine periodic risks, particularly during higher-severity events.

1,659

Total FEMA Flood Claims

~83

Est. Claims/Year

Cincinnati has a moderate flood history with 1,659 FEMA claims. Flood events can contaminate drinking water and overwhelm treatment systems.

How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure.

Residents in flood-prone areas should consider flood insurance even outside FEMA zones - over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.

Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.