Orange or black stains from your well: iron, manganese, or both

Which metal makes which stain

A common clue: water that comes out of the tap clear, then turns orange or forms black specks after it sits. That means the metal was dissolved and is reacting with air. If particles are visible right away, the metal is already in solid (oxidized) form.^[source] That difference matters a lot for choosing treatment, so note what you see before you test.

Not every stain is iron or manganese. Blue-green stains usually point to copper from corroding pipes, which is a separate problem often linked to acidic water.^[source] Our low pH and pinhole leaks guide covers that one.

Three different thresholds, and why reports disagree

You'll see different numbers for "too much" iron and manganese depending on who's measuring. They're not contradictory; they answer different questions.

• EPA secondary standards (0.3 mg/L iron, 0.05 mg/L manganese) are non-enforceable guidelines for taste, color and staining. EPA says contaminants with secondary standards aren't considered a health risk at those levels.^[source] Above them, you'll likely notice stains.
• EPA's manganese health advisory (0.3 mg/L) is a separate, non-enforceable level set because of concerns about neurological effects from regularly drinking water above it.^[source] This is why manganese deserves a real number, not just a stain check.
• North Carolina's 2L groundwater standards use 0.3 mg/L for iron and 0.05 mg/L for manganese.^[source]

The UNC Superfund Research Program's county tables use higher cutoffs on purpose: 2,500 µg/L (2.5 mg/L) for iron, an NC DEQ level, and 300 µg/L (0.3 mg/L) for manganese, the EPA health advisory.^[source] So their percentages count wells well above the point where staining starts.

How common iron and manganese are in local wells

Very common. These figures describe wells tested through North Carolina's state lab between 1998 and 2019, not every well, and they use the higher UNC cutoffs above:^[source]

At the lower staining thresholds, the share is higher still. NC DWR found 19.0% of Union County samples above 0.3 mg/L iron and 26.5% above 0.05 mg/L manganese between 2000 and 2011.^[source] Your county's page in our service areas lists the local figures; for example, Cabarrus County.

How to test

1. Step 1

   Check your new-well report

   Iron and manganese are both required tests for new private wells in North Carolina,^[source] so you may already have numbers. Our new-well test guide explains how to read them.

2. Step 2

   Get a current certified-lab panel

   Include iron, manganese, pH and hardness. pH and hardness change which treatments will work. Our water testing service sets this up.

3. Step 3

   Note the form

   Tell the lab or your dealer whether water comes out clear and stains later, or comes out cloudy. That points to dissolved vs. already-oxidized metal.

Treatment categories (chosen after the test)

Because iron and manganese stain everything the water touches, they're usually treated where water enters the home.^[source] Penn State Extension describes these main approaches, each suited to a different range of results:^[source]

• Water softener: can remove dissolved iron and small amounts of manganese, but generally only when pH is above about 6.7, the water is moderately hard, and dissolved iron is under about 5 mg/L. Oxidized iron fouls the resin.
• Oxidizing filters (greensand or birm): oxidize and filter in one tank. Greensand handles moderate levels of both metals with regular regeneration; birm needs enough dissolved oxygen and higher pH, and is less reliable for manganese.
• Oxidation plus filtration: a feed pump adds an oxidant (often chlorine) ahead of a filter. Used for high combined levels; may need carbon afterward for taste.
• Aeration or catalytic carbon: other options that can work in the right conditions, each with its own requirements.

If your well is also acidic, a neutralizer often goes first, because pH affects how well the next stage works. Our iron and manganese treatment page explains how we put a system together, and our water softener page covers when a softener alone is enough.

These are whole-house systems that tie into plumbing. Clear Bridge Water supplies and sizes the equipment; here's how licensed installation works.

Every option above needs upkeep: backwashing, regenerant or media refills, and an annual check. A Care Plan covers that along with a retest to confirm it's still working.