Well Water in Washington County: What to Test and Why

Radon, chloride, and arsenic are present in Washington County groundwater and well owners should be aware of them. Chloride and radon exceed EPA health standards in this area, so testing is important for anyone using a private well.

Chloride and radon come from different sources. Chloride enters groundwater from saltwater that sits beneath the sand and clay layers in this region--the underground geology here naturally contains salt deposits from ancient oceans. Radon comes from natural radioactive decay in the rock itself. Arsenic occurs naturally in the sand and clay layers that make up the aquifer system.

Groundwater in Washington County is moderately hard, driven by moderate levels of iron and sodium. The sand and clay layers that hold the water release iron and sodium into the groundwater as water moves through them. These mineral characteristics show up in many wells across the county, though the amount varies from well to well.

Wells in Washington County commonly have chloride and radon at levels that exceed EPA health standards. Radon is a radioactive gas that builds up in homes and increases the risk of lung cancer over time. Chloride at high levels can be a concern for people on sodium-restricted diets and can damage plumbing and appliances. Arsenic has also been detected in some county wells and poses health risks with long-term exposure.

County well water tends to be moderately hard, which means you might notice some staining on fixtures and dishes. Iron in the water can leave orange or brown stains on sinks, tubs, and laundry. Hard water can also make soap less effective and may shorten the lifespan of water heaters and dishwashers over time. The sodium levels are moderate, so this is less of a taste concern than in some areas.

We recommend testing your well to find out what is actually in your water, since every well is different and yours could have higher or lower levels than the county average. A comprehensive panel that checks for metals, minerals, bacteria, and chemicals typically costs between two hundred and four hundred dollars and is the best way to understand your situation. Testing will show you exactly what needs treatment, whether that is a radon mitigation system, a water softener, or another solution. Contact your county health department or a certified lab to arrange testing.