Well Water in Rockingham County: What to Test and Why

Groundwater in Rockingham County contains radon, chloride, and sulfate at levels high enough to exceed EPA health standards. These contaminants appear in enough wells that well owners should test their water and understand where they come from.

Radon enters groundwater naturally from radioactive rock in the Valley and Ridge formation beneath the county. Chloride and sulfate also come from the bedrock itself--these minerals dissolve slowly as water moves through the ground layers. The rock type in this area releases these salts into water more readily than softer rock would.

Groundwater in Rockingham County is soft, with low iron and low sodium, which means it stays clean-tasting and does not carry heavy mineral loads. The soft water here results from the specific rock layers that make up the Valley and Ridge aquifers in this region. Most wells in the county show this same soft-water pattern, though radon, chloride, and sulfate levels vary from well to well.

Wells in Rockingham County can have chloride, radon, and sulfate above EPA health standards. Radon is a radioactive gas that builds up in lungs over time and increases cancer risk. Chloride at elevated levels can be harmful to people with heart disease or high blood pressure. Sulfate in drinking water can cause digestive problems, especially in children and infants.

The good news is that the mineral content in county wells is generally low, so you probably won't see staining from iron or the white scale buildup that hard water causes on fixtures and inside pipes. Your water should taste clean without strange flavors or odors from minerals. Appliances like water heaters and dishwashers should not wear out prematurely from mineral buildup.

We recommend testing your well water since every well is different and yours could have higher or lower levels than what is common in the county. Testing is the only way to know what is actually in your water so you can treat it properly. A comprehensive panel that checks for metals and minerals costs between $200 and $400 and will give you a complete picture. Radon can be treated with aeration systems, and chloride or sulfate issues can be addressed with appropriate filtration.