Drinking water quality · 2024
· Verified
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 — 8 sit at or above that limit.
- Reporting year
- 2024
- Contaminants measured
- 15
- Over federal limit
- 8
- Approaching the limit
- 1
- Worst contaminant
- Chlorite
- Service area
- TX
- ChloriteDisinfection byproducts · Reported level2024 mg/Llimit 0.8 mg/L · 2530.0× the limit
- BariumMetals · Reported level2024 mg/Llimit 2 mg/L · 1012.0× the limit
- FluorideInorganic chemicals · Reported level2024 mg/Llimit 4 mg/L · 506.0× the limit
- NitrateInorganic chemicals · Reported level2024 mg/Llimit 10 mg/L · 202.4× the limit
- SeleniumMetals · Reported level2024 ug/Llimit 50 ug/L · 40.5× the limit
- HAA5Disinfection byproducts · Reported level2024 ug/Llimit 60 ug/L · 33.7× the limit
- TTHMDisinfection byproducts · Reported level2024 ug/Llimit 80 ug/L · 25.3× the limit
- CyanideInorganic chemicals · Reported level2024 ug/Llimit 200 ug/L · 10.1× the limit
PFAS — EPA UCMR5 (2023–2025)
2 PFAS compounds 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.
Lithium
● Detected (no federal limit)near national p90 (76.59999999999991 mg/L across detecting U.S. systems)
PFBA
● Detected (no federal limit)above national p90 (18 ng/L across detecting U.S. systems)
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.
Historical readings · EPA Six-Year Review (2012–2019)
2 contaminants historically over EPA limits in Mcallen, TX
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) |
|---|---|---|---|
GROSS BETA worst: 2014 | 6.2 mrem/yr 1.6× | 4 mrem/yr | '12'14'15'17'18 |
TTHM worst: 2012 | 0.123 mg/L 1.5× | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
CHLORITE worst: 2017 | 0.85 mg/L 85% | 1 mg/L | '13'14'15'16'17'18'19 |
CYANIDE worst: 2015 | 0.16 mg/L within above national p90 | 0.2 mg/L | '14'15'17'18'19 |
HAA5 worst: 2015 | 0.0393 mg/L within | 0.06 mg/L | '12'13'14'15'16'17'18'19 |
RADIUM 226 228 worst: 2012 | 2.9 pCi/L within near national p90 | 5 pCi/L | '12 |
DEHP worst: 2013 | 0.002 mg/L within | 0.006 mg/L | '13 |
ARSENIC worst: 2016 | 0.0033 mg/L within below national p90 | 0.01 mg/L | '12'13'14'15'16 |
FLUORIDE worst: 2013 | 1.07 mg/L within | 4 mg/L | '12'13'14'15'16'17'18'19 |
GROSS ALPHA worst: 2017 | 4 pCi/L within | 15 pCi/L | '14'15'17'18 |
CARBON TETRACHLORIDE worst: 2014 | 0.001 mg/L within below national p90 | 0.005 mg/L | '14 |
SELENIUM worst: 2015 | 0.0069 mg/L within | 0.05 mg/L | '12'13'14'15'16'19 |
ANTIMONY worst: 2012 | 0.000592 mg/L within below national p90 | 0.006 mg/L | '12 |
BARIUM worst: 2012 | 0.128 mg/L within near national p90 | 2 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE worst: 2018 | 0.39 mg/L within | 10 mg/L | '12'13'14'15'16'17'18'19 |
METHOXYCHLOR worst: 2014 | 0.0002 mg/L within | 0.04 mg/L | '14 |
THALLIUM worst: 2012 | 0.000009 mg/L within | 0.002 mg/L | '12 |
CHROMIUM worst: 2012 | 0.000412 mg/L within below national p90 | 0.1 mg/L | '12 |
URANIUM worst: 2018 | 0.0027 ug/L within below national p90 | 30 ug/L | '14'15'17'18 |
COPPER worst: 2012 | 0.223 mg/L below national p90 | — | '12'13'14'15'16'17'18 |
MBAA worst: 2012 | 0.0099 mg/L | — | '12'13'14'15'16'17'18'19 |
LEAD worst: 2012 | 0.00553 mg/L | — | '12'15'18 |
DBAA worst: 2012 | 0.0189 mg/L | — | '12'13'14'15'16'17'18'19 |
DCAA worst: 2012 | 0.0054 mg/L | — | '12'13'14'15'16'17'18'19 |
MCAA worst: 2012 | 0.0045 mg/L | — | '12'19 |
TCAA worst: 2012 | 0.0042 mg/L | — | '12'13'14'15'16'18 |
BROMODICHLOROMETHANE worst: 2012 | 0.0248 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMOFORM worst: 2012 | 0.0445 mg/L | — | '12'13'14'15'16'17'18'19 |
CHLOROFORM worst: 2012 | 0.0084 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2012 | 0.0458 mg/L | — | '12'13'14'15'16'17'18'19 |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChloramineA longer-lasting disinfectant made by combining chlorine with ammonia. | 3.22 mg/LAverageNivel promedio | 4 mg/LMRDL | Approaching the limit |
People also ask about Mcallen, TX's water
+Is Mcallen, TX tap water safe to drink in 2024?
The 2024 Consumer Confidence Report for the Mcallen, TX water utility lists 8 contaminants at or above the federal limit: Chlorite, Barium, Fluoride, Nitrate, Selenium, HAA5, TTHM, and Cyanide. 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 Mcallen, TX tap water?
15 contaminants were measured in Mcallen, TX's 2024 Consumer Confidence Report, spanning metals, disinfection byproducts, and inorganic chemicals. 14 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 Mcallen, TX tap water?
8 contaminants in Mcallen, TX's 2024 report sit at or above the federal limit: Chlorite (2530.0× the limit); Barium (1012.0× the limit); Fluoride (506.0× the limit); Nitrate (202.4× the limit); Selenium (40.5× the limit); HAA5 (33.7× the limit); TTHM (25.3× the limit); Cyanide (10.1× 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 Mcallen, TX tap water?
The contaminant with the highest measured value relative to its federal limit in the 2024 report is Chlorite, at 2530.0× the federal threshold. It belongs to the disinfection byproducts family of contaminants.
+Are any contaminants in Mcallen, TX tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: 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.