Groundwater in San Patricio County contains arsenic, chloride, uranium, and fluoride among other contaminants. Several of these exceed EPA health standards, making them a concern for well owners.
The coastal location and underlying rock layers naturally contain these elements. Saltwater from the Gulf of Mexico seeps into the groundwater in this low-lying area, raising chloride levels. Arsenic and uranium occur naturally in the rock itself and dissolve into water as it moves underground.
Water in this county is very hard, driven by elevated calcium and magnesium in the groundwater. The coastal plain's sandy and clay layers allow minerals to accumulate as water filters downward. These characteristics appear in most wells across the county.
Wells in San Patricio County can contain arsenic, uranium, fluoride, and manganese at levels that exceed EPA health standards. Arsenic and uranium are radioactive elements that can increase cancer risk with long-term exposure. Fluoride at high levels can affect bone and tooth development, especially in children. Manganese can harm the nervous system with prolonged exposure.
The county's water is very hard and contains high sodium levels. Very hard water leaves white scale buildup inside pipes, on fixtures, and in appliances like water heaters and dishwashers, which can shorten their lifespan. The high sodium gives the water a salty taste that some people notice right away. Hard water also makes it harder to get soap to lather and can leave spots on dishes.
We recommend testing your well water with a comprehensive metals and minerals panel, since multiple contaminants exceed health standards in this county. Your individual well 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 panel runs between $200 and $400. Treatment options like reverse osmosis systems or water softeners can address multiple concerns at once.
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 ⓘ |
|---|---|---|---|---|---|
| Chloride | 61 | 75% | Moderate | High | |
| Uranium | 18 | 22% | Moderate | High | |
| Arsenic | 51 | 18% | Moderate | High | |
| Iron | 68 | 15% | Moderate | Moderate | |
| Manganese | 53 | 6% | Moderate | Moderate | |
| Sulfate | 60 | 5% | Moderate | Moderate | |
| Fluoride | 212 | 0% | High | Low | |
| HFPO-DA (GenX) ⓘ municipal | 34 | 0% | Moderate | Safe | |
| Lead | 50 | 0% | Moderate | Low | |
| Nitrate | 65 | 0% | Moderate | Low | |
| PFHxS ⓘ municipal | 34 | 0% | Moderate | Safe | |
| PFNA ⓘ municipal | 34 | 0% | Moderate | Safe | |
| PFOA ⓘ municipal | 34 | 0% | Moderate | Safe | |
| PFOS ⓘ municipal | 34 | 0% | Moderate | Safe | |
| Hardness | 61 | — | Moderate | Low | |
| PFBS ⓘ municipal | 34 | — | Moderate | Low | |
| pH | 56 | — | Moderate | Low | |
| Sodium | 11 | — | Low | 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.
Loading recent water news…