Drinking water quality · 2025
· Verified
What's in Columbus, OH tap water
53 contaminants were measured in the Columbus, OH water system's 2025 annual report. Each is shown below against its federal limit — 11 sit at or above that limit.
- Reporting year
- 2025
- Contaminants measured
- 53
- Over federal limit
- 11
- Approaching the limit
- 0
- Worst contaminant
- Cadmium
- Service area
- OH
- CadmiumMetals · Reported level2025 mg/Llimit 0.005 mg/L · 405000.0× the limit
- BariumMetals · Reported level2025 mg/Llimit 2 mg/L · 1012.5× the limit
- AtrazineVOCs & pesticides · Reported level2025 ug/Llimit 3 ug/L · 675.0× the limit
- ChlorineDisinfectants · Reported level2025 mg/Llimit 4 mg/L · 506.3× the limit
- FluorideInorganic chemicals · Reported level2025 mg/Llimit 4 mg/L · 506.3× the limit
- SimazineVOCs & pesticides · Reported level2025limit 4 · 506.3× the limit
- BromateDisinfection byproducts · Reported level2025 ug/Llimit 10 ug/L · 202.5× the limit
- NitrateInorganic chemicals · Reported level2025 mg/Llimit 10 mg/L · 202.5× the limit
- HAA5Disinfection byproducts · Reported level2025 ug/Llimit 60 ug/L · 33.8× the limit
- TTHMDisinfection byproducts · Reported level2025 ug/Llimit 80 ug/L · 25.3× the limit
- pHPhysical & aggregate · Reported level7.8limit 6.5 · 1.2× the limit
PFAS — EPA UCMR5 (2023–2025)
1 PFAS compound detected in Columbus, OH
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
Lithium
● Detected (no federal limit)below national p90 (76.59999999999991 mg/L across detecting U.S. systems)
Where your water comes from · EPA SDWIS
Columbus, OH's drinking water comes from ground water, drawn from 3 sources.
Source
- WELL · 3
Treatment
- COLUMBUS GROVE VILLAGE
Distribution
Historical readings · EPA Six-Year Review (2012–2019)
13 historically-detected contaminants in Columbus, OH
Every U.S. public water system reports compliance-monitoring data to EPA. The Six-Year Review releases the 2012–2019 window as a single dataset — here's what your system reported, year by year. Values shown are the highest detection per analyte per year, compared to the federal MCL.
| Contaminant | Worst detection | EPA limit | Years (2012–2019) |
|---|---|---|---|
TTHM worst: 2013 | 0.0509 mg/L within | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
FLUORIDE worst: 2013 | 1.21 mg/L within | 4 mg/L | '13'16'19 |
HAA5 worst: 2013 | 0.018 mg/L within | 0.06 mg/L | '12'13'14'15'16'17'18 |
BARIUM worst: 2016 | 0.079 mg/L within below national p90 | 2 mg/L | '13'16'19 |
COPPER worst: 2012 | 1.4 mg/L above national p90 | — | '12'13'14'15'16'17'18'19 |
LEAD worst: 2012 | 0.04 mg/L | — | '12'13'14'15 |
DBAA worst: 2012 | 0.0017 mg/L | — | '12'13'14'15'17 |
DCAA worst: 2012 | 0.0076 mg/L | — | '12'13'14'15'16'17'18 |
TCAA worst: 2012 | 0.0032 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMODICHLOROMETHANE worst: 2012 | 0.0096 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMOFORM worst: 2012 | 0.0006 mg/L | — | '12'13'14'15'16'17'18'19 |
CHLOROFORM worst: 2012 | 0.0132 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2012 | 0.0052 mg/L | — | '12'13'14'15'16'17'18'19 |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Cadmium | 2025 mg/LReported levelWhen we checked | 0.005 mg/LMCL | At or above the limit |
+By source (4)— When we checked, Hap Cremean Water Plant, Columbus Water +1 more
| |||
| AluminumA common element sometimes used as a treatment coagulant. | 0.016Reported levelColumbus Water | 0.05MCL | Within the limit |
| ZincA naturally occurring metal that can also enter water from corroding pipes. | 0.256Reported levelColumbus Water | 5MCL | Within the limit |
| Antimony | Not detectedReported levelColumbus Water | 0.006MCL | None detected |
| ArsenicA naturally occurring element that also enters water from industry and agriculture. | Not detectedReported levelColumbus Water | 0.01MCL | None detected |
| Beryllium | Not detectedReported levelColumbus Water | 0.004MCL | None detected |
| Chromium, TotalTotal chromium — the sum of all chromium forms, from natural deposits and industrial discharge. | Not detectedReported levelColumbus Water | 0.1MCL | None detected |
| IronA naturally occurring metal common in groundwater. | Not detectedReported levelColumbus Water | None set | None detected |
| MercuryA toxic metal from erosion of natural deposits and industrial runoff. | Not detectedReported levelColumbus Water | 0.002MCL | None detected |
| NickelA metal from natural deposits and industrial discharge. | Not detectedReported levelColumbus Water | None set | None detected |
| SeleniumA trace element from natural deposits and industrial discharge. | Not detectedReported levelColumbus Water | 0.05MCL | None detected |
| Thallium | Not detectedReported levelColumbus Water | 0.002MCL | None detected |
| CalciumA naturally occurring mineral that contributes to water hardness. | 34Reported levelColumbus Water | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 8Reported levelColumbus Water | None set | Detected — no federal limit |
| PotassiumA naturally occurring mineral from rock and soil. | 4.2Reported levelColumbus Water | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 58Reported levelColumbus Water | None set | Detected — no federal limit |
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| AtrazineA widely used agricultural herbicide that reaches water through runoff. | 2025 ug/LReported levelWhen we checked | 3 ug/LMCL | At or above the limit |
+By source (5)— When we checked, Dublin Road Water Plant, Hap Cremean Water Plant +2 more
| |||
| Simazine | 2025Reported levelWhen we checked | 4MCL | At or above the limit |
+By source (5)— When we checked, Dublin Road Water Plant, Hap Cremean Water Plant +2 more
| |||
| Benzene | Not detectedReported levelColumbus Water | 0.005MCL | None detected |
| Dichloromethane | Not detectedReported levelColumbus Water | 0.005MCL | None detected |
| Ethylbenzene | Not detectedReported levelColumbus Water | 0.7MCL | None detected |
| TetrachloroethyleneAn industrial solvent (PCE) used in dry cleaning and degreasing. | Not detectedReported levelColumbus Water | 0.005MCL | None detected |
| Toluene | Not detectedReported levelColumbus Water | 1MCL | None detected |
| TrichloroethyleneAn industrial solvent (TCE) used in metal degreasing. | Not detectedReported levelColumbus Water | 0.005MCL | None detected |
| XylenesA group of industrial solvents found in gasoline and paint. | Not detectedReported levelColumbus Water | 10MCL | None detected |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 2025 mg/LReported levelWhen we checked | 4 mg/LMCL | At or above the limit |
+By source (4)— When we checked, Dublin Road Water Plant, Hap Cremean Water Plant +1 more
| |||
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| BromateA disinfection byproduct formed when bromide-containing water is treated with ozone. | 2025 ug/LReported levelWhen we checked | 10 ug/LMCL | At or above the limit |
+By source (4)— When we checked, Dublin Road Water Plant, Columbus Water +1 more
| |||
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits. | 2025 mg/LReported levelWhen we checked | 10 mg/LMCL | At or above the limit |
+By source (5)— When we checked, Dublin Road Water Plant, Hap Cremean Water Plant +2 more
| |||
| SulfateA naturally occurring mineral from rock and soil. | 130.5Reported levelColumbus Water | 250MCL | Within the limit |
| ChlorideA naturally occurring salt compound. | 52Reported levelColumbus Water | 250MCL | Within the limit |
| Ammonia | Not detectedReported levelColumbus Water | None set | None detected |
| Cyanide | Not detectedReported levelColumbus Water | 0.2MCL | None detected |
| BromideA naturally occurring salt found in source water. | 0.055Reported levelColumbus Water | None set | Detected — no federal limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| pHA measure of how acidic or basic the water is. | 7.8Reported levelColumbus Water | 6.5MCL | At or above the limit |
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 313Reported levelColumbus Water | 500MCL | Within the limit |
| AlkalinityA measure of the water's capacity to neutralize acids. | 48Reported levelColumbus Water | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 115Reported levelColumbus Water | None set | Detected — no federal limit |
| Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content. | 512Reported levelColumbus Water | None set | Detected — no federal limit |
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 2025Reported levelWhen we checked | None set | Detected — no federal limit |
+By source (4)— When we checked, Hap Cremean Water Plant, Dublin Road Water Plant +1 more
| |||
| TurbidityA measure of cloudiness from suspended particles in the water. | 0.68 NTUReported levelHap Cremean Water Plant | None set | Detected — no federal limit |
+By source (3)— Columbus Water, Hap Cremean Water Plant, Dublin Road Water Plant
| |||
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Cryptosporidium | Not detectedReported levelColumbus Water | None set | None detected |
| Giardia lamblia | Not detectedReported levelColumbus Water | None set | None detected |
| Total ColiformA group of bacteria used as an indicator of overall water-system sanitation. | 0Reported levelColumbus Water | None set | None detected |
People also ask about Columbus, OH's water
+Is Columbus, OH tap water safe to drink in 2025?
The 2025 Consumer Confidence Report for the Columbus, OH water utility lists 11 contaminants at or above the federal limit: Cadmium, Barium, Atrazine, Chlorine, Fluoride, Simazine, Bromate, Nitrate, HAA5, TTHM, and pH. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.
+What contaminants are in Columbus, OH tap water?
53 contaminants were measured in Columbus, OH's 2025 Consumer Confidence Report, spanning metals, vocs & pesticides, and disinfection byproducts. 33 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Which contaminants exceed federal limits in Columbus, OH tap water?
11 contaminants in Columbus, OH's 2025 report sit at or above the federal limit: Cadmium (405000.0× the limit); Barium (1012.5× the limit); Atrazine (675.0× the limit); Chlorine (506.3× the limit); Fluoride (506.3× the limit); Simazine (506.3× the limit); Bromate (202.5× the limit); Nitrate (202.5× the limit); HAA5 (33.8× the limit); TTHM (25.3× the limit); pH (1.2× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.
+What is the worst contaminant in Columbus, OH tap water?
The contaminant with the highest measured value relative to its federal limit in the 2025 report is Cadmium, at 405000.0× the federal threshold. It belongs to the metals family of contaminants.
+Where does the data on this page come from?
Every value is transcribed from Columbus, OH's 2025 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.
+How often is Columbus, OH's water quality data updated?
Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2025 report; a new report will replace it once the utility publishes its next annual update.