What's in the Water in Columbus, OH?
Monitoring data for Columbus, Ohio shows 1 distinct contaminant detected in the public water supply — Nitrate. Of these, 1 exceeded the EPA Maximum Contaminant Level.
Contaminants Detected in Columbus
| Contaminant | Detected | EPA Limit (MCL) | Status |
|---|---|---|---|
| Nitrate | 10.5 mg/l | 10 mg/l | Exceeds limit |
Detected levels are the highest reported across Columbus systems for each contaminant. MCL = EPA Maximum Contaminant Level, the legal safety ceiling. Source: EPA SDWIS monitoring data.
Safety & Violations
| Metric | Value |
|---|---|
| Average Safety Score | 40/100 (F worst) |
| Public Water Systems | 1 |
| Population Served | 1,305,946 |
| Health Violations | 3 |
| Monitoring Violations | 0 |
| Contaminant Exceedances | 3 |
| Enforcement Actions | 4 |
Frequently Asked Questions
Monitoring data for Columbus, Ohio shows 1 distinct contaminant detected in the public water supply — Nitrate. Of these, 1 exceeded the EPA Maximum Contaminant Level.
The 1 public water system serving Columbus, Ohio (population 1,305,946) average a Water Safety Score of 40/100, with a worst grade of F. These systems have 3 health-based violations and 3 contaminant exceedances on record.
Columbus, Ohio is served by 1 public water system, together supplying water to roughly 1,305,946 people. The worst safety grade among them is F.
Yes. 1 contaminant exceeded the EPA Maximum Contaminant Level (MCL) in Columbus: Nitrate. An exceedance means a detected level was higher than the legal safety limit at least once during monitoring.
The Water Safety Score (0-100, graded A-F) weighs health-based violations (40%), contaminant exceedances (30%), enforcement history (20%), and monitoring violations (10%), using EPA Safe Drinking Water Information System (SDWIS) data from the last 10 years.
Request your utility's annual Consumer Confidence Report (CCR), consider an independent test from a state-certified lab, and use an NSF-certified filter targeting any contaminant of concern. For lead specifically, run cold water 30 seconds before drinking.
More about Columbus
Monitoring data for Columbus, Ohio shows 1 distinct contaminant detected in the public water supply — Nitrate. Of these, 1 exceeded the EPA Maximum Contaminant Level.
The data source behind this answer is the EPA Safe Drinking Water Information System (SDWIS). Every figure on the page traces back to that source; the methodology page describes the inputs and the refresh cadence in full detail.
For readers turning this answer into action: cross-reference against the underlying the EPA Safe Drinking Water Information System (SDWIS) record before acting on time-sensitive decisions. The site renders the data as it was published; subsequent revisions can shift the picture, and the live federal data is always the authoritative current reference.
Source: EPA Ground Water and Drinking Water, 2026.