Why Does My Well Water Have So Much Iron?
By Geoffrey Sperring
March 06, 2025
Have you had the unpleasant experience of opening the faucet in a remote cabin or rural area only to discover the water has a strange color and taste? Chances are the water contains iron and manganese, some of the more abundant metals in the earth. Read on to discover what causes iron in well water for the 43 million Americans who rely on it for drinking water.
This May Also Interest You: How Much Do Home Water Filtration Systems Cost?
Signs of Too Much Iron in Well Water
It's relatively easy to detect the presence of iron in drinking water from its color, taste and smell. Typical signs of high iron in water include:
Color. Water running from a faucet may have a red, brown or yellowish color.
Stains. You'll see yellow, red or brown stains on plumbing fixtures, dishes and your laundry.
Taste. The water has a strong metallic taste.
Slime. The water has a brown, red or yellow slime that clogs pipes, faucets, washing machines and water heaters.
Smell. Sometimes, the water has the odor of rotten eggs.
Sediment. Rust-colored particles settle when water is left standing, such as in a glass.
What Causes Iron in Well Water?
The soils and rocks in many parts of the country have minerals that contain high levels of iron and also manganese. As it rains or snow melts, water seeps into the ground. When it comes into contact with these minerals, it can dissolve iron. Depending on the part of the country, the number of wells contaminated with iron varies; for example, in North Carolina, the percentage is 27%.
Why Is There so Much Iron in My Well Water?
Wells located close to iron-contaminated groundwater typically contain high iron levels. While rarely toxic, these amounts commonly exceed the EPA water standard of 0.3 milligrams per liter.
Types of Iron Commonly Found in Well Water
There are four main types of iron liable to be discovered in well water:
Ferrous iron. A soluble iron called ferrous carbonate, it comes from deep groundwater sources where there's little oxygen.
Ferric iron. Known as clear water iron, it's an insoluble powder with red particles that settle out of the water.
Organic iron. Often found in shallow wells, it’s a compound formed when a natural organic acid dissolves iron. It's typically yellow or brown and leaves a black residue.
Bacterial iron. Certain bacteria feed on iron, leaving a red, slimy residue that’s harmless but that may support unhealthy organisms.
More Related Articles:
Is It Safe to Drink Well Water With Iron in It?
Yes, it's usually safe to drink well water containing iron, provided the concentration is below 10 milligrams per liter. Iron and manganese are essential metals for good health and are safe as long as the amounts are below action levels. In Minnesota, drinking water iron levels below 10 milligrams per liter are considered safe, while the Connecticut action level for manganese in water supplies is 0.3 milligrams per liter.
What Can Be Done About It?
It's possible to remove iron from well water using specialized iron removal water treatments such as:
Filtration. Ferrous and ferric iron can be removed using a manganese greensand oxidizing filter or an activated carbon filter. It's important to take note of the correct time to replace these filters.
Water softener to remove iron. Water softeners that use ion exchange resin beds can remove iron, calcium and magnesium from the water for amounts of up to 10 milligrams per liter.
Chemical oxidation. This process uses chlorine or hydrogen peroxide to precipitate dissolved iron, which is then removed by filtration. These chemicals are dangerous, and the process requires expert supervision, but it's appropriate for removing high levels of iron and manganese.
Aeration. Suitable for high concentrations, aeration by injecting air or using calcium or sodium hypochlorite converts soluble iron into ferric iron that's removable by filtration.
Professional Well Water Services
You may need expert help to understand what causes high iron in well water. Professional water testing services can identify the type and concentration of iron and manganese in your well water. According to the CDC, you should also use a state-certified laboratory to test your well water for coliform bacteria, nitrates and acidity at least once a year.
View Plans in Your Area
Popular


Apr 01, 2024


Apr 26, 2021
Get the latest news, tips and promotional messages, including special offers.