Drinking water quality · 2024
What's in Billings, MT tap water
18 contaminants were measured in the Billings, MT water system's 2024 annual report. Each is shown below against its federal limit — 2 sit at or above that limit.
- Reporting year
- 2024
- Contaminants measured
- 18
- Over federal limit
- 2
- Approaching the limit
- 1
- Worst contaminant
- TTHM
- Service area
- MT
Where your water comes from · EPA SDWIS
Billings, MT's drinking water comes from surface water, drawn from 2 sources.
Source
- INTAKE 1 YELLOWSTONE RIVER
- INTAKE 2 EMERGENCY
Treatment
- TREATMENT PLANT FOR YELLOWSTONE RIVER
- TREATMENT PLANT CHAPPLE CHLORINE BOOSTER
- TREATMENT PLANT STAPLES CHLORINE BOOSTER
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.
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. | 17–91 ug/LRangeof Levels | None set | At or above the limit |
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 17–66 ug/LRangeof Levels | None set | At or above the limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ArsenicA naturally occurring element that also enters water from industry and agriculture. | 8.87 ug/LReported levelSystem-wide | 0 ug/LMCLG | Approaching the limit |
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 5 ug/L90th percentileAt the tap | 0 ug/LMCLG | Within the limit |
| CopperA metal that enters water from corroding household plumbing. | 0.192 mg/L90th percentileAt the tap | 1.3 mg/LMCLG | Within the limit |
| AluminumA common element sometimes used as a treatment coagulant. | 0–59.5 ug/LRangeRange Detected | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 0–13.6 mg/LRangeRange Detected | None set | Detected — no federal limit |
| PotassiumA naturally occurring mineral from rock and soil. | 1.23–3.34 mg/LRangeRange Detected | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 0–24 mg/LRangeRange Detected | None set | Detected — no federal limit |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Chlorine Free | 1.99 mg/LReported levelSystem-wide | 4 mg/LMRDLG | Within the limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 0.51 mg/LReported levelSystem-wide | 4 mg/LMCLG | Within the limit |
| NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits. | 0.55 mg/LReported levelSystem-wide | 10 mg/LMCLG | Within the limit |
| ChlorideA naturally occurring salt compound. | 7.46–12.7 mg/LRangeRange Detected | None set | Detected — no federal limit |
| SulfateA naturally occurring mineral from rock and soil. | 19.2–71.5 mg/LRangeRange Detected | None set | Detected — no federal limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| AlkalinityA measure of the water's capacity to neutralize acids. | 44–172 mg/LRangeRange Detected | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 52–165 mg/LRangeRange Detected | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 7.44–8.29RangeRange Detected | None set | Detected — no federal limit |
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 102–354 mg/LRangeRange Detected | None set | Detected — no federal limit |
People also ask about Billings, MT's water
+Is Billings, MT tap water safe to drink in 2024?
The 2024 Consumer Confidence Report for the Billings, MT water utility lists 2 contaminants at or above the federal limit: TTHM and HAA5. 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 Billings, MT tap water?
18 contaminants were measured in Billings, MT's 2024 Consumer Confidence Report, spanning metals, inorganic 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 Billings, MT tap water?
2 contaminants in Billings, MT's 2024 report sit at or above the federal limit: TTHM (1.1× the limit); HAA5 (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 Billings, MT tap water?
The contaminant with the highest measured value relative to its federal limit in the 2024 report is TTHM, at 1.1× the federal threshold. It belongs to the disinfection byproducts family of contaminants.
+Are any contaminants in Billings, MT tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: Arsenic. 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 Billings, MT'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 Billings, MT'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.