Webb County groundwater contains radon, arsenic, chloride, sulfate, fluoride, uranium, lead, and manganese. Several of these contaminants exceed EPA health standards at levels that warrant attention from well owners.
These contaminants come from the rocks and minerals deep underground in this region. The Texas coastal uplands aquifer system here contains naturally occurring uranium, radon, and arsenic in the rock layers. Saltwater intrusion from the nearby coast adds chloride and other salts to the groundwater, while sulfate dissolves from minerals in the surrounding rock.
Groundwater in this county is not hard, but it is very high in sodium and sulfate, driven by the salty geology and coastal influence of the area. These minerals dissolve naturally from the rocks and accumulate as water moves slowly through the ground. These characteristics are common across wells throughout Webb County.
Wells in Webb County commonly have arsenic, lead, uranium, and radon above EPA health standards. Arsenic and uranium can damage your kidneys and bones over time and raise cancer risk. Lead harms children's brain development and learning. Radon is a radioactive gas that increases lung cancer risk when you breathe it in.
Wells here also contain very high sodium and sulfate levels that affect how your water tastes and feels. Sodium gives water a salty taste that some people notice right away. Sulfate can create a rotten egg smell and may cause loose stools if you drink a lot of it. The county's water is soft, so you won't see scale buildup, but the other minerals still matter for your health and comfort.
We recommend testing your well water right away with a comprehensive panel since multiple contaminants exceed health standards in this county. Every well is different--yours could have higher or lower levels than what is common here. Testing is the only way to know what is actually in your water so you can treat it properly. A comprehensive metals and minerals panel runs between $200 and $400. Treatment options like reverse osmosis filters or activated carbon can remove many of these contaminants.
Not sure if your well is affected? Get certified results in 5–7 days.
Test Your Well Water with Tap Score →| Contaminant | Samples ⓘ | % Above MCL ⓘ | Distribution ⓘ | Confidence ⓘ | Risk ⓘ |
|---|---|---|---|---|---|
| Radon | 1 | 100% | Low | High ⓘ | |
| Chloride | 37 | 68% | Moderate | High | |
| Sulfate | 37 | 65% | Moderate | High | |
| Arsenic | 203 | 14% | High | Moderate | |
| Iron | 181 | 14% | High | Moderate | |
| Manganese | 173 | 9% | High | Moderate | |
| Uranium | 71 | 7% | Moderate | Moderate | |
| Fluoride | 271 | 2% | High | Low | |
| Lead | 164 | 1% | High | Low | |
| HFPO-DA (GenX) ⓘ municipal | 12 | 0% | Low | Safe | |
| Nitrate | 72 | 0% | Moderate | Low | |
| Nitrite | 36 | 0% | Moderate | Low | |
| PFHxS ⓘ municipal | 12 | 0% | Low | Safe | |
| PFNA ⓘ municipal | 12 | 0% | Low | Safe | |
| PFOA ⓘ municipal | 12 | 0% | Low | Safe | |
| PFOS ⓘ municipal | 12 | 0% | Low | Safe | |
| Sodium | 37 | — | Moderate | Low | |
| pH | 37 | — | Moderate | Low | |
| PFBS ⓘ municipal | 12 | — | Low | Safe | |
| Hardness | 37 | — | Moderate | Low |
MCL = Maximum Contaminant Level (EPA limit for public water; used as benchmark for private wells). Distribution shows % of sampled wells in each concentration band. Methodology.
* Microbial contaminants (E. coli, coliform) reflect only samples from the last 10 years.
Data shows potential risk — a certified test confirms whether your water is affected.
Order a Tap Score Test →Population-level CDC data. Not individual risk prediction.
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