Drinking water quality · 2024
What's in Mesa, AZ tap water
23 contaminants were measured in the Mesa, AZ water system's 2024 annual report. Each is shown below against its federal limit.
- Reporting year
- 2024
- Contaminants measured
- 23
- Over federal limit
- 0
- Approaching the limit
- 1
- Service area
- AZ
PFAS — EPA UCMR5 (2023–2025)
1 PFAS compound approaching EPA limits in Mesa, AZ
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.
PFHxS (Perfluorohexane sulfonic acid)
● Approaching limit (93%)PFBS
● Detected (no federal limit)PFHxA
● Detected (no federal limit)Where your water comes from · EPA SDWIS
Mesa, AZ's drinking water comes from ground water, drawn from 33 sources.
Source
- WL-55-629618 - CITY
- WL-55-508798 - CITY
- WL-55-511595 - DESERT
- WL-55-517843 - CITY
- + 29 more
Treatment
- TP001 - CLO2, BROWN CAP
- TP004 - CL2, AS
- TP003 - CL2
- + 3 more
Distribution
Also buys water from PHOENIX CITY OF.
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-based3 violations on record · most recent Jan 2003resolved
- Other1 violation on recordresolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ArsenicA naturally occurring element that also enters water from industry and agriculture. | 8.37 ug/LReported levelSystem-wide | None set | Approaching the limit |
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 0.00501 mg/L90th percentileAt the tap | 0.015 mg/LAction level | Within the limit |
| Chromium, TotalTotal chromium — the sum of all chromium forms, from natural deposits and industrial discharge. | 24.7 ug/LReported levelSystem-wide | None set | Within the limit |
| CopperA metal that enters water from corroding household plumbing. | 0.17 mg/L90th percentileAt the tap | 1.3 mg/LAction level | Within the limit |
| SeleniumA trace element from natural deposits and industrial discharge. | 3 ug/LReported levelSystem-wide | None set | Within the limit |
| BariumA metal from erosion of natural deposits and industrial discharge. | 0.114 mg/LReported levelSystem-wide | 2 mg/LMCL | Within the limit |
| SodiumA naturally occurring salt component. | 210 mg/LReported levelSystem-wide | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits. | 7.88 mg/LReported levelSystem-wide | 10 mg/LMCL | Within the limit |
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 1.11 mg/LReported levelSystem-wide | 4 mg/LMCL | Within the limit |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. | 51 ug/LRunning annual avgSystem-wide | None set | Within the limit |
| BromateA disinfection byproduct formed when bromide-containing water is treated with ozone. | 5.8 ug/LRunning annual avgSystem-wide | None set | Within the limit |
| Chlorite | 0.36 mg/LAverageSystem-wide | 1 mg/LMCL | Within the limit |
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 18 ug/LRunning annual avgSystem-wide | None set | Within the limit |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | 5.4 pCi/LReported levelSystem-wide | 15 pCi/LMCL | Within the limit |
| Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements. | 0.9 pCi/LReported levelSystem-wide | 5 pCi/LMCL | Within the limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| TurbidityA measure of cloudiness from suspended particles in the water. | 0.3 NTUHighest single sampleSystem-wide | 1 NTUTreatment technique | Within the limit |
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 1.6Running annual avgSystem-wide | None set | Detected — no federal limit |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Dehp | 1.7 ug/LReported levelSystem-wide | None set | Within the limit |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 0.71 mg/LRunning annual avgSystem-wide | 4 mg/LMCL | Within the limit |
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| TetrachloroethyleneAn industrial solvent (PCE) used in dry cleaning and degreasing. | 0.62 ug/LReported levelSystem-wide | 5 ug/LMCL | Within the limit |
| DBCP1,2-dibromo-3-chloropropane — a banned soil fumigant pesticide. | 24 ng/LReported levelSystem-wide | None set | Within the limit |
| TrichloroethyleneAn industrial solvent (TCE) used in metal degreasing. | 0.54 ug/LReported levelSystem-wide | 5 ug/LMCL | Within the limit |
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total ColiformA group of bacteria used as an indicator of overall water-system sanitation. | 4Reported levelSystem-wide | None set | Detected — no federal limit |
People also ask about Mesa, AZ's water
+Is Mesa, AZ tap water safe to drink in 2024?
Every one of the 23 contaminants measured in Mesa, AZ's 2024 Consumer Confidence Report is below its federal limit. "Safe" under the EPA's drinking-water standards is health-based, not aesthetic — but by those standards, no measured contaminant in this report exceeds its enforceable threshold. Individual health concerns (e.g. immunocompromised, infant, pregnancy) may warrant additional filtering regardless of compliance.
+What contaminants are in Mesa, AZ tap water?
23 contaminants were measured in Mesa, AZ's 2024 Consumer Confidence Report, spanning metals, disinfection byproducts, and vocs & pesticides. 12 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Are any contaminants in Mesa, AZ 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 Mesa, AZ'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 Mesa, AZ'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.