How To Know Iron Is In Your Water – Color, Stains And Tests

Water that contains iron can appear reddish (insoluble iron), yellowish-brown (organic iron) or clear with red particles that settle at the bottom (soluble iron). A metallic taste, clogged pipes, yellow teeth and laundry stains also indicate iron in water. Iron test kits and certified laboratory testing can determine the amount and type of iron in water.

Iron makes up about 5% of the earth’s crust, and is one of the most abundant resources on earth. When rain falls or snow melts, it dissolves iron and seeps it into rivers, lakes and underground water sources.

Let’s take a more detailed look into the different methods you can use to determine if there is iron in your water. We’ll also go through lots of helpful information about iron in water such as its good and bad effects, and the types of iron that could be in your water.

  • High concentrations of iron can give water a metallic taste and odor, while also creating a reddish-brown or yellowish color.
  • Water that contains high levels of iron over long periods of time can stain appliances and clog pipes.
  • Home DIY test kits and laboratory tests are the best methods to determine how much iron is in your water, and which type of iron.

Iron In Your Water

Three forms of iron can be present in tap water:

1. Ferrous Iron: this is also known as soluble iron and is clear and colorless.

However, after standing for a while, the water becomes reddish as the ferrous iron oxidizes into the ferric iron particles that settle at the bottom of the glass.

2. Ferric Iron: this is also known as insoluble iron.

It gives water a reddish-brown color similar to rust.

3. Organic Iron: organic iron is formed when iron reacts with organic acids, which are widespread.

Organic iron is usually yellow or brown and, in some cases, it may be completely colorless. It’s mostly found in shallow wells or wells that are affected by surface water.

There are a few ways to confirm that there is iron in your water. Each of these methods has pros and cons, and some are more accurate than others.

Ways to test for iron in water. A metallic taste, reddish-brown stains on clothing and dishes, clogged pipes and reddish-brown or even yellow water indicate iron is present. DIY home test kits, or accredited laboratory testing can also be conducted.
How to know iron is in you water. Image created for

1. Water Aesthetics – taste, color and smell

When present in high enough concentrations, iron can cause your tap water to have an unpleasant metallic taste, smell, and even color.

The aesthetics of your tap water is usually an early hint of the presence of iron in your water.

Iron in water also gives your food and beverages that same metallic taste and sometimes, it can cause these drinks and meals to have an unpleasant dark black color.

Green leafy veggies boiled in iron-containing tap water can wilt and turn dark, while tea and coffee can turn black from tannins reacting with organic iron.

If the iron present in your tap water is ferrous iron, the water will initially be colorless when it first comes out of the tap. However, after letting it stand for a while, the ferrous iron will react with the oxygen in the air and become ferric iron which is reddish and insoluble.

After standing for a while, the particles will settle to the bottom of the container. Here are some easy color tests you can do at home:

How to test for the different types of iron in water. Water with ferrous or soluble iron will appear clear, but red or brown particles will settle when left to stand. Ferric or insoluble iron will make tap water appear reddish brown. Iron oxidizing bacteria will cause reddish slime and organic iron leads to yellow or brown water,
The types of iron in water, and how to test and treat them.


  • Cheap identification method
  • Easy and quick


  • Unreliable
  • Does not indicate the quantity or type of iron in the water

2. Iron Test Kits

Using an at-home water test kit is an easy way of detecting the presence of iron in your tap water.

If there is iron in your water, the iron test kit will also give you an estimate of the amount of iron in mg/l or parts per million (PPM).

The iron test kit contains some test strips – which are strips of paper or plastic impregnated with some chemical substances that change color when they react with iron – as well as a color chart. How to use an iron test kit depends on the specifications of the manufacturer. However, the procedure is typically straightforward.

  • Simply dip one of the test strips into a sample of your tap water for a few seconds.
  • Remove the strip from the water and wait for a few more seconds for the test strip color to change.
  • Compare the color of the strip to the color chart to get an estimate of the amount of iron that is present in your water.

The home water test kit tells you if there’s iron present in your tap water and gives you an estimate of how much iron there is.

However, this test doesn’t tell you what form the iron is in – whether the ferric form or the ferrous form.


  • Affordable
  • Gives relatively accurate estimates of iron levels in water
  • Easy to use


  • Does not differentiate the forms of iron present in the water.

3. Red, brown or yellow stained laundry and dishes

Iron in water can become oxidized and form iron oxides. These iron oxides, such as rust, easily attach themselves to the fibers of clothing or to the surfaces of dishes and fittings.

This type of staining can be an indication of iron in your water, but it can also simply be a sign that one of your appliances is corroding. For example, if you are only seeing signs of iron-staining on your dishes then your dishwasher (or the pipes that connect to it) may have begun to corrode.


  • Simple identification method.


  • Does not identify the form or amount of iron
  • Can be misleading and identify iron from an appliance rather than the water supply.

4. Certified Laboratory Testing

Getting your tap water tested by an accredited or certified laboratory is a much better way of detecting and quantifying iron in your tap water than doing it yourself using home iron test kits.

Usually, when you order a test, the laboratory will send you a kit that comes with instructions on how to collect samples to be sent back to the lab.

This test gives you a more detailed report of the iron in your water. It can give you information about the forms of iron – whether ferric or ferrous – that is present in your water and the amount of iron in your water.

Our recommended laboratory test for iron is the Tap Score Iron Water Test.

Once you get the test kit, collect samples of your drinking water into the available containers according to the instructions in the manual.

This test has a turnaround time of about 5 days and you will get a detailed report about the iron present in your water.


  • The results are very accurate. It is the most accurate method of checking for the presence of iron in the water.


  • Slower than other methods.

5. Yellow teeth

Drinking water high in iron can cause tooth enamel to change color, usually yellow. In fact, studies have also found that iron can absorb onto dentin, the part of the tooth that lies beneath the enamel.

Identifying yellowing of your teeth, and your family members can be a sign there are high concentrations of iron in your water.


  • Simple, easy method.


  • Inaccurate – the staining may be the result of other minerals, food etc.
  • Slow method, as teeth stains take considerable time to develop.

6. Clogged Pipes

Some bacteria thrive in the presence of iron, and are called iron-oxidizing bacteria (or ‘iron-bacteria’ for short).

While these bacteria may not be directly harmful to health, they feed on iron and leave behind slimy iron waste deposits.

The resulting sludge has a foul odor and can accumulate over time and block your plumbing supply pipes. It can also affect your appliances like dishwashers and washing machines.


  • An easy, but indirect method of identifying iron in water.


  • Inaccurate – the staining may be the result of other minerals, food etc.
  • Slow method, as teeth stains take considerable time to develop.

If you get your water from a public water system and not a private one, you should contact your utility provider.

This will tell you whether the excess iron in your water is from the public water supply or if the issue is from your home’s plumbing system. 

The Effects of Excess Iron in Water

The presence of iron in water doesn’t usually affect our body’s health negatively. So, a large amount of iron is considered a secondary contaminant, affecting just the taste, smell, and look of water.

However, drinking water with more than 0.3mg/l iron can put you at risk of health issues, such as iron overload, poor skin, and dental cavities.

Poor skin 

When you drink water containing too much iron, it can affect the health of your skin by increasing your risk of cellulitis, a type of bacterial skin infection.

Excess iron in the body can also increase the formation of free radicals in your body. Free radicals are highly reactive molecules that can damage previously healthy cells. When free radicals attack skin cells, early signs of ageing such as skin wrinkling and thinning will begin to appear.

Iron overload

This is when there is too much iron in the body.

This excess iron can form deposits on organs, causing them to malfunction. Iron overload is not a common side effect of excess iron in drinking water.

It usually only occurs when someone has hemochromatosis, a rare inherited illness, caused by a genetic mutation that leads to an abnormal increase of iron absorption from the intestine.

Dental Issues 

Drinking water containing excess iron can lead to dental health problems such as discolored or stained teeth, gum infections such as periodontitis, and even dental cavities.

In normal quantities, iron is an element that acts as a very important mineral in the body where it is used in the formation of blood and the transport of oxygen to the various parts of the body. 

The body finds it a bit difficult to absorb iron from water, so most of the iron the body uses is gotten from iron-containing foods such as meat, spinach, and other leafy greens.

What Is The Acceptable Level of Iron in Drinking Water?

Iron is a widespread element and is very likely present in your tap water.

The EPA has set the maximum acceptable level of iron in tap water at 0.3mg/l. However, some wells are likely to contain higher quantities of iron, particularly in regions that have high levels of iron in their soil and rocks.

U.S. Environmental Protection Agency

When iron is present in higher quantities than this, it begins to affect the water aesthetics (e.g. its taste, smell, and appearance) and may even be dangerous to health.

Apart from the health and aesthetic concerns, excess iron in water also affects your plumbing, appliances, and laundry.                                              

How does iron get into tap water?

Iron enters our tap water from the dissolution of iron-bearing minerals in rocks and soil over time, and from surface runoff after rain. Corrosion of pipes can also cause iron to enter our water supply.

If you live in an area where the rocks and soil have high iron content, then rain and melted snow can dissolve the iron and seep it into your well water. This is called surface runoff.

Also, if the pipes supplying water to your house from your well are made of iron, continuous exposure of these pipes to water and oxygen can cause them to rust and deteriorate.

As water runs through the rusted pipes, the rust flakes off and falls into the water and then into your appliances.

Can I contact my utility provider to know the amount of iron in my water?

Your utility provider is required to publish a report, at least once every year, on the type and amount of substances in the water they supply. However, the quantity of iron stated in this report may not reflect that of your tap water because iron may be introduced into your water supply via old iron pipes as they transport the water to its point of use.

Contacting your utility provider may not be the go-to option to find out the iron content of your tap water because iron could enter your water through old iron pipes or other parts of your home’s plumbing

However, after using any of the methods explained in the article to confirm if there is iron in your water, you can contact your community utility provider to help you figure out the source of the iron.

What Do I Do If My Well Water Has Excess Iron?

If your well water has excess iron, you can try to bypass the iron-rich water by extending your well casing or screen deeper into the ground. However, this will only be effective if you are able to reach a different aquifer that is not within rocks of high iron content.

Digging a new well depends on the presence of a suitable, accessible underground aquifer, preferably at a location with soil that is possibly less iron-rich.

Theresa Orr

Theresa Orr is an Earth Scientist who specializes in determining past climates from rocks using geochemistry. Her passion for clean water drives her to breakdown the science to provide easy to understand information that everyone can read.

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