What's in the Water in Columbia, MD?
Monitoring data for Columbia, Maryland shows 2 distinct contaminants detected in the public water supply — Combined Filter Effluent, Total Coliform (TCR). None exceeded the EPA Maximum Contaminant Level in the reported samples.
Contaminants Detected in Columbia
| Contaminant | Detected | EPA Limit (MCL) | Status |
|---|---|---|---|
| Combined Filter Effluent | 0.5 NTU | 1 NTU | Within limit |
| Total Coliform (TCR) | 2.5 % positive | 5 % positive | Within limit |
Detected levels are the highest reported across Columbia 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 | 80/100 (B worst) |
| Public Water Systems | 1 |
| Population Served | 286,158 |
| Health Violations | 0 |
| Monitoring Violations | 0 |
| Contaminant Exceedances | 0 |
| Enforcement Actions | 7 |
Frequently Asked Questions
Monitoring data for Columbia, Maryland shows 2 distinct contaminants detected in the public water supply — Combined Filter Effluent, Total Coliform (TCR). None exceeded the EPA Maximum Contaminant Level in the reported samples.
The 1 public water system serving Columbia, Maryland (population 286,158) average a Water Safety Score of 80/100, with a worst grade of B. These systems have no health-based violations on record.
Columbia, Maryland is served by 1 public water system, together supplying water to roughly 286,158 people. The worst safety grade among them is B.
No. In the reported monitoring data for Columbia, no detected contaminant exceeded its EPA Maximum Contaminant Level (MCL).
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 Columbia
Monitoring data for Columbia, Maryland shows 2 distinct contaminants detected in the public water supply — Combined Filter Effluent, Total Coliform (TCR). None exceeded the EPA Maximum Contaminant Level in the reported samples.
This answer pulls from the EPA Safe Drinking Water Information System (SDWIS), the authoritative federal source for U.S. public drinking-water safety. The headline number above is the direct answer; what follows is the additional context most readers need to use the answer for a real decision rather than just a fact lookup.
A practical caveat: the headline answer above reflects the most recent the EPA Safe Drinking Water Information System (SDWIS) vintage; underlying data is often revised for months after first publication, and the right reference for any specific decision is whichever vintage is current at the time of the decision. The as-of date is stamped on every page.
Source: EPA Ground Water and Drinking Water, 2026.