Is iron in well water dangerous to drink?

At the levels found in most private wells, no. The EPA's Secondary Maximum Contaminant Level for iron is 0.3 mg/L. That's an aesthetic standard based on taste, odor, and staining, not health effects. Iron at typical well concentrations isn't a recognized health threat for adults. If you're also seeing a sulfur smell or suspect manganese, those are separate issues worth testing for.

Why does my well water stain everything orange?

Orange staining is almost always dissolved ferrous iron that oxidizes when it hits air. The water looks clear when it comes out of the tap, but the iron reacts with oxygen and forms rust-colored particles that settle on porcelain, laundry, and fixtures. The higher your iron concentration, the faster and darker the staining.

What causes iron in well water?

Iron is one of the most abundant elements in the earth's crust. Groundwater picks it up as it moves through iron-bearing rock and soil. Wells drilled into sandstone, shale, or areas with natural iron deposits tend to have higher concentrations. There's no human activity required. It's just geology.

Will a water softener remove iron from my well?

A softener can remove small amounts of dissolved ferrous iron, typically up to 1-2 mg/L depending on the unit and conditions. But iron is hard on softener resin. It coats the resin beads over time, reducing ion-exchange capacity. At higher iron levels, you need a dedicated iron filter before the softener, not instead of it.

How do I know if I have iron bacteria?

Iron bacteria leave a distinct signature: orange, reddish, or brownish slime inside your toilet tank, on the inside of the lid, or around fixtures. The slime has a musty or sometimes sulfur-like smell. It's not a health threat, but it fouls filters and water softeners fast. A lab test can confirm it, but the toilet tank check is usually enough to know.

Iron in Well Water: Orange Stains, Metallic Taste, and What to Do

Orange slime in your toilet tank. Rust-colored rings in the sink that won’t scrub off. Laundry that comes out of the wash looking dingy and stained. A metallic taste in your morning coffee that makes you wonder if something is seriously wrong with your well.

Iron is the most common complaint from private well owners in the US. And while it’s a genuine nuisance, it’s not the health emergency it can feel like when your fixtures look like they’re rusting from the inside out.

The Three Forms of Iron (and Why They Matter)

This is the part most people skip, and it’s the reason a lot of well owners spend money on treatment that doesn’t work. Iron in well water comes in three distinct forms, and they don’t respond to the same treatments.

Ferrous iron (dissolved) is the most common. The water runs perfectly clear straight from the tap. Fill a glass and let it sit. Leave some in a white sink. The water will turn orange or rust-colored as the dissolved iron reacts with oxygen in the air. That oxidation process turns soluble iron into rust particles, and those particles are what leave the stains. Most wells with iron have this form.

Ferric iron (particulate) is already oxidized before it reaches your tap. The water comes out visibly orange or red, sometimes with visible particles floating in it. This form has already gone through the oxidation step somewhere in your well or plumbing. It’s less common than ferrous iron but easier to identify.

Iron bacteria are naturally occurring microorganisms that feed on dissolved iron. They’re not pathogens. They don’t make you sick. But they create orange or reddish slime in your toilet tank, inside pipe joints, and around fixture openings. Check the inside of your toilet tank lid. If there’s orange or rust-colored slime coating the walls, you likely have iron bacteria. They also produce byproducts that create a musty or sulfur-like odor, and they foul water softener resin and filters faster than iron alone.

You can have one form, two forms, or all three at the same time.

What Iron Actually Does to Your Health

Not much, at typical well water concentrations. The EPA’s Secondary Maximum Contaminant Level (Secondary MCL) for iron is 0.3 milligrams per liter (mg/L). Secondary MCLs are not health-based limits. They’re guidance standards for aesthetics: taste, odor, and color. The EPA explicitly notes they are not federally enforceable health regulations.

Iron is an essential nutrient. Adults need 8 to 18 mg per day from food and water combined. Drinking water with 1 or 2 mg/L of iron contributes only a fraction of that. At those levels, you’re more likely to notice the staining than any effect on your body.

The concern people sometimes raise is iron overload, a condition called hemochromatosis. That’s a genetic disorder affecting iron metabolism, not something caused by drinking water with elevated iron levels.

One thing worth clarifying: manganese often shows up in the same wells as iron, and manganese does have a health advisory from the EPA. But that’s a separate contaminant with different treatment requirements. If your water has iron, get it tested for manganese too. See manganese in well water for what to know about that problem.

What Iron Does to Your House

This is where iron earns its reputation. High iron well water is hard on everything.

Orange and rust-colored staining on toilets, sinks, tubs, and showers. The staining gets worse over time and becomes harder to remove as it builds up. Some fixtures need replacement because the stains have permanently penetrated the surface.

Laundry. Iron in the wash water leaves rust-colored stains on white clothes and dingy discoloration on other fabrics. Standard detergent won’t fix it. Chlorine bleach can actually make iron staining worse by oxidizing dissolved iron onto the fabric.

Appliances and irrigation. Iron deposits build up inside dishwashers, ice makers, and water heaters. Irrigation heads clog. Drip systems fail. The particulate iron that causes these problems is often so fine it passes through coarse screens.

Water softener resin fouling is one of the more expensive consequences. Iron coats the resin beads in a softener, blocking the ion exchange sites that make the softener work. A softener running on high-iron water without pre-treatment will lose capacity faster and need more frequent regeneration. Eventually the resin needs replacement. If you have a softener, protecting it from iron is one of the main arguments for adding an iron filter upstream.

If you’re also getting a sulfur or rotten egg smell, that often points to iron bacteria or a separate hydrogen sulfide problem. The two frequently co-occur. Hydrogen sulfide in well water covers that issue separately.

How to Test for Iron

A basic home test strip can tell you roughly whether iron is present and at what approximate concentration. That’s useful for a quick sanity check.

But a certified lab test is what you actually need before buying any equipment. Here’s why: the form of iron matters as much as the concentration. A lab test can distinguish between ferrous and ferric iron, detect iron bacteria, and measure manganese and other co-occurring contaminants. Without knowing what form you’re dealing with, you’re guessing at treatment.

Collect a water sample according to the lab’s instructions and mail it in. Results typically take a week. The well water testing guide walks through what to test for, which labs to use, and how to read the results.

Treatment in Brief

Treatment depends entirely on which form of iron you have. This is why the lab test matters.

For ferrous dissolved iron, oxidizing filters are the standard approach. Air injection systems, greensand filters, and Birm media all work by oxidizing dissolved iron to particulate form and then filtering out the particles. The right choice depends on your iron concentration, pH, and whether manganese is also present.

For ferric particulate iron, a sediment filter may be enough if concentrations are moderate. Higher levels typically need a more capable filtration stage.

For iron bacteria, shock chlorination of the well and plumbing is the first step. You can’t filter your way out of iron bacteria without killing the organisms first. After chlorination, a filtration system handles any remaining iron. Some systems require periodic chlorine injection to keep bacteria from re-establishing.

For a full treatment guide: How to Remove Iron from Well Water. For equipment: Best Iron Filters for Well Water.

One Recommendation Before You Buy Anything

If you’re seeing orange staining, get a lab test first.

This is the advice most people skip because they want to solve the problem right now. But iron treatment equipment is expensive. Oxidizing filters, air injection systems, and whole-house setups can run $800 to $3,000 or more depending on the system. Buying the wrong one means spending that money and still having orange water. A sediment filter won’t touch dissolved ferrous iron. A standard filter won’t solve an iron bacteria problem.

The lab test costs $50 to $150. It tells you exactly what you’re dealing with. That’s worth doing first.

WaterAnswer.com provides general information only. This page is not a substitute for water quality testing by a certified laboratory or guidance from a licensed water treatment professional.