Drinking water quality · 2024
What's in Mcallen, TX tap water
15 contaminants were measured in the Mcallen, TX water system's 2024 annual report. Each is shown below against its federal limit.
- Reporting year
- 2024
- Contaminants measured
- 15
- Over federal limit
- 0
- Approaching the limit
- 2
- Service area
- TX
PFAS — EPA UCMR5 (2023–2025)
1 PFAS compound detected in Mcallen, TX
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.
PFBA
● Detected (no federal limit)Where your water comes from · EPA SDWIS
Mcallen, TX's drinking water comes from surface water, drawn from 3 sources.
Source
- INTAKE 1 - PLANT SITE / SOUTH
- INTAKE 3 - NORTH PLANT
- 1 - SWTP
Treatment
- SW SWTP - 2500 W EXPWY 83
- SW PLANT - EXPANSION
- SWTP - NORTH / 8313 N BENTSEN RD
- + 1 more
Distribution
Also buys water from CITY OF EDINBURG, CITY OF HIDALGO WATER SYSTEM, and 2 more.
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. | 18.5–69.2 ug/LRangeRange of Individual Samples | None set | Approaching the limit |
| Chlorite | 0.503 mg/LReported levelSystem-wide | 0.8 mg/LMCLG | Within the limit |
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 29.4 ug/LReported levelSystem-wide | None set | Within the limit |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChloramineA longer-lasting disinfectant made by combining chlorine with ammonia. | 3.22 mg/LAverageSystem-wide | 4 mg/LMCL | Approaching the limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Cyanide | 100 ug/LReported levelSystem-wide | None set | Within the limit |
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 0.63 mg/LReported levelSystem-wide | 4 mg/LMCLG | Within the limit |
| NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits. | 0.12 mg/LReported levelSystem-wide | 10 mg/LMCLG | Within the limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ArsenicA naturally occurring element that also enters water from industry and agriculture. | 3.8 ug/LReported levelSystem-wide | 0 ug/LMCLG | Within the limit |
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 0.0023 mg/L90th percentileAt the tap | 0.015 mg/LAction level | Within the limit |
| CopperA metal that enters water from corroding household plumbing. | 0.1122 mg/L90th percentileAt the tap | 1.3 mg/LMCLG | Within the limit |
| BariumA metal from erosion of natural deposits and industrial discharge. | 0.094 mg/LReported levelSystem-wide | 2 mg/LMCLG | Within the limit |
| SeleniumA trace element from natural deposits and industrial discharge. | Not detected ug/LReported levelSystem-wide | None set | None detected |
| LithiumA naturally occurring element found in some groundwater. | 45 ug/LAverageSystem-wide | None set | Detected — no federal limit |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| UraniumA naturally occurring radioactive metal from erosion of natural deposits. | 2.3 ug/LReported levelSystem-wide | 0 ug/LMCLG | Within the limit |
| Gross Beta Particle ActivityGross beta particle activity — a combined measure of beta-emitting radioactive substances. | 7.2 pCi/LReported levelSystem-wide | 0 pCi/LMCLG | Detected — no federal limit |
People also ask about Mcallen, TX's water
+Is Mcallen, TX tap water safe to drink in 2024?
Every one of the 15 contaminants measured in Mcallen, TX'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 Mcallen, TX tap water?
15 contaminants were measured in Mcallen, TX's 2024 Consumer Confidence Report, spanning metals, disinfection byproducts, and inorganic chemicals. 10 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 Mcallen, TX tap water approaching the federal limit?
2 contaminants are between 80% and 100% of the federal limit in this report: TTHM and Chloramine. 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 Mcallen, TX'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 Mcallen, TX'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.