Treatment for iron in well water
Treatment for iron in well water is a common occurrence if you live in the northeastern states where iron is liberally deposited in the granite strata. Iron is the most common metal found in the universe, and comprises at least 5% of the earth‘s crust. Thus, it stands to reason that some iron will eventually find its way into all the water on earth. This includes your well water.
Heavy rains dissolve iron particles that then enter underground aquifers. Melting snow also helps iron enter into well water. If you have a well, at some point, you’ll have some iron deposits enter the water. Nature makes it unavoidable. Iron in well water treatment is an option to remove that element from your drinking and bathing water.
If beverages made with water from your well start to taste weird, or if you notice a drop in water pressure or appliances that use water start to discolor, you may have iron in your well water. Also, if you notice a yellow/brown staining or discoloration in your water that affects laundry, toilets, tubs, appliances, fixtures or any other water-using system, you likely have iron in your water.
Fortunately, there are a variety of effective water treatment systems for the removal of iron. Determining the most effective system requires proper diagnosis of the type of iron.
How do you know which iron is in your well water?
There are telltale signs of the most-common four types of iron in well water listed below. Keep in mind more than one type of iron may be present in a single sample of water. All four types of iron cause staining, metallic taste, and fouling of pipes and plumbing.
A significant amount of iron in well water presents a challenge for water conditioning, as different removal methods need to be applied to reduce the iron to acceptable levels.
Ferrous iron
This is also called clear iron because it invisibly dissolves in water. Ferrous iron is common in well water. The slight acidity of rainwater causes the iron to dissolve into solution. If you draw a glass of water containing ferrous iron, the water will appear clear possibly for a day or more. Ferrous iron tends to stain fixtures a reddish-brown color as it is exposed to oxygen, or whenever it comes in contact with oxidizing chemicals such as soaps and detergents.
Ferric iron
This is iron that has already oxidized (rusted) and is therefore insoluble. A glass of water containing ferric iron quickly develops a film of orange on the bottom as the particles settle out of solution. Ferric iron causes staining of fixtures, laundry and the dishwasher, as well as fouling plumbing. This form is very common in our region’s groundwater.
Organic iron
Disclaimer: organic iron and colloidal iron are extremely uncommon and can only be determined by a water professional.
This is ferrous iron that has been metabolized by iron bacteria as part of their diet. These organisms form jelly-like deposits of ferric iron and can be identified by clumps of iron scum in water and an oily sheen on the surface of water, especially in toilet tanks. Organic iron or bacterial iron is challenging to filter out of water.
Colloidal iron
This iron is composed of extremely fine particles (smaller than 1 micron), and due to their size and electrical charge, the particles remain in suspension. A glass containing colloidal iron will have a reddish-pink tinge to it. These iron particles are so tiny they have a specific gravity similar to water. It can take a very long time for them to finally settle out of solution.
Treatment for iron in well water
The two most effective methods for removal of ferrous iron is ion exchange (softening), which pulls the iron molecules out of water by electrochemical attraction, as well as oxidation and filtration. The latter method uses air or a chemical oxidizer to convert the ferrous iron to ferric particles, which can then be mechanically filtered out.
Organic iron is more difficult to remove, as the biological mass that encapsulates the scum tends to protect the iron from traditional removal methods. The incoming water can be treated by a chemical feed system utilizing a strong oxidizer to destroy the biomass. Then the residue can be mechanically filtered out. Organic iron is difficult to treat under most circumstances; thankfully it is a rare occurrence.
Colloidal iron also presents a serious challenge for residential filtration, as the most effective removal involves injecting an adhesive agent such as alum to bind the tiny particles together into large enough clumps that they fall out of solution and can be mechanically trapped. Fortunately, this problem is quite rare.
Secondwind Water’s water treatment professionals have decades of experience in treating well water with iron contamination. Contact one of our certified water specialists for proper testing and treatment of your well water.