Drinking water quality · 2024
What's in Columbia, SC tap water
31 contaminants were measured in the Columbia, SC water system's 2024 annual report. Each is shown below against its federal limit — 5 sit at or above that limit.
- Reporting year
- 2024
- Contaminants measured
- 31
- Over federal limit
- 5
- Approaching the limit
- 2
- Worst contaminant
- PFOS
- Service area
- SC
- PFOSPFAS ("forever chemicals") · Average6.8999999999999995 ng/L
- PFOAPFAS ("forever chemicals") · Average5.5 ng/L
- ChloriteDisinfection byproducts · Reported level1.32 mg/Llimit 1 mg/L · 1.3× the limit
- HAA5Disinfection byproducts · Range11–65 ug/L
- ChloramineDisinfectants · Range0.01–4.3 mg/Llimit 4 mg/L · 1.1× the limit
PFAS — EPA UCMR5 (2023–2025)
2 PFAS compounds above EPA limits in Columbia, SC
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.
PFOS (Perfluorooctane sulfonic acid)
● Over EPA limit (2.1×)PFOA (Perfluorooctanoic acid)
● Over EPA limit (1.7×)HFPO-DA (GenX chemicals)
● Approaching limit (92%)PFPeA
● Detected (no federal limit)PFBS
● Detected (no federal limit)PFHxA
● Detected (no federal limit)PFHpA
● Detected (no federal limit)Where your water comes from · EPA SDWIS
Columbia, SC's drinking water comes from surface water, drawn from 2 sources.
Source
- LAKE MURRAY
- BROAD RIVER CANAL
Treatment
- CANAL WTP (A40010)
- LAKE MURRAY WTP (A40011)
Distribution
Compliance history
Federal Safe Drinking Water Act violation & enforcement records (EPA SDWIS). A violation is a regulatory determination by the state or EPA — separate from the measured levels above.
- Maximum contaminant level exceededHealth-based8 violations on record · most recent Dec 2024resolved
- Treatment technique violationHealth-based5 violations on record · most recent Nov 2015resolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Chlorite | 1.32 mg/LReported levelSystem-wide | 1 mg/LMCL | At or above the limit |
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 11–65 ug/LRangeSystem-wide | None set | At or above the limit |
| TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. | 15–67 ug/LRangeSystem-wide | None set | Approaching the limit |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChloramineA longer-lasting disinfectant made by combining chlorine with ammonia. | 0.01–4.3 mg/LRangeSystem-wide | 4 mg/LMCL | At or above the limit |
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 552 ug/LReported levelSystem-wide | None set | Within the limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 6 ug/LReported levelSystem-wide | None set | Within the limit |
| CopperA metal that enters water from corroding household plumbing. | 0.17 mg/LReported levelSystem-wide | None set | Within the limit |
| SeleniumA trace element from natural deposits and industrial discharge. | 3.6 ug/LReported levelSystem-wide | None set | Within the limit |
| CalciumA naturally occurring mineral that contributes to water hardness. | 12.6 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| IronA naturally occurring metal common in groundwater. | 92 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 1.9 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| ManganeseA naturally occurring metal from soil and rock. | 14.6 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 8.1 mg/LAverageSystem-wide | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 0.83 mg/LReported levelSystem-wide | 4 mg/LMCL | Within the limit |
| ChlorideA naturally occurring salt compound. | 10.8 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| SulfateA naturally occurring mineral from rock and soil. | 21.6 mg/LAverageSystem-wide | None set | Detected — no federal limit |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements. | 0.735 pCi/LReported levelSystem-wide | 5 pCi/LMCL | Within the limit |
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | 0.872 pCi/LReported levelSystem-wide | 15 pCi/LMCL | Within the limit |
| Gross Beta Particle ActivityGross beta particle activity — a combined measure of beta-emitting radioactive substances. | 5.36 pCi/LReported levelSystem-wide | None set | Detected — no federal limit |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Nitrate Nitrite | 0.43 mg/LReported levelSystem-wide | 10 mg/LMCL | Within the limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ColorA measure of visible tint in the water. | 0RangeSystem-wide | None set | None detected |
| AlkalinityA measure of the water's capacity to neutralize acids. | 26 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 36 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 8AverageSystem-wide | None set | Detected — no federal limit |
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total ColiformA group of bacteria used as an indicator of overall water-system sanitation. | 0–2.6 %RangeSystem-wide | None set | Detected — no federal limit |
People also ask about Columbia, SC's water
+Is Columbia, SC tap water safe to drink in 2024?
The 2024 Consumer Confidence Report for the Columbia, SC water utility lists 5 contaminants at or above the federal limit: PFOS, PFOA, Chlorite, HAA5, and Chloramine. 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 Columbia, SC tap water?
31 contaminants were measured in Columbia, SC's 2024 Consumer Confidence Report, spanning metals, pfas ("forever chemicals"), and physical & aggregate. 6 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 Columbia, SC tap water?
5 contaminants in Columbia, SC's 2024 report sit at or above the federal limit: PFOS (1.7× the limit); PFOA (1.4× the limit); Chlorite (1.3× the limit); HAA5 (1.1× the limit); Chloramine (1.1× 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 Columbia, SC tap water?
The contaminant with the highest measured value relative to its federal limit in the 2024 report is PFOS, at 1.7× the federal threshold. It belongs to the pfas ("forever chemicals") family of contaminants.
+Are any contaminants in Columbia, SC tap water approaching the federal limit?
2 contaminants are between 80% and 100% of the federal limit in this report: Hexafluoropropylene oxide dimer acid and TTHM. Approaching means measured but not in violation — a margin that can close quickly if conditions change.
+Where does the data on this page come from?
Every value is transcribed from Columbia, SC's 2024 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 Columbia, SC'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 2024 report; a new report will replace it once the utility publishes its next annual update.