Well Water in Cook County: What to Test and Why

Cook County's groundwater contains manganese, sulfate, iron, and nitrate. Iron and manganese exceed EPA health standards in this county, which is a concern that deserves attention.

These contaminants come from the rock and soil beneath the county. The surficial aquifer sits in loose sand and sediment near the surface, where water moves freely through it. Iron and manganese dissolve naturally from minerals in the rock as water flows through. Nitrate seeps down from fertilizers and septic systems in the soil above, since the shallow aquifer offers little protection from surface sources.

Groundwater in this county is hard, driven by calcium and magnesium that dissolve from the rock layers below. The sandy and sediment-based geology here allows these minerals to build up in the water over time. Hard water is common across wells throughout Cook County.

Wells in Cook County contain iron, manganese, nitrate, and sulfate at levels above EPA health standards. Iron and manganese can damage your nervous system with long-term exposure. Nitrate is especially dangerous for babies and can prevent their bodies from carrying oxygen properly. Sulfate at high levels can cause digestive problems, particularly in people who are not used to it.

Hard water is common in county wells and can leave spots and scale on dishes, shower doors, and faucets. You might notice a metallic or unpleasant taste in your water. Hard water can also shorten the lifespan of water heaters, dishwashers, and other appliances by causing buildup inside them.

We recommend getting your well tested to find out what is actually in your water. Every well is different, and your well may have higher or lower levels than what is common in the county. A comprehensive metals and minerals panel costs between two and four hundred dollars and is the only way to know what needs treatment. Treatment options like water softeners, iron filters, or reverse osmosis systems can address multiple concerns at once.