Chloramination FAQs

What is chloramination?

Chloramination is the process of adding ammonia to drinking water, which already has chlorine added as a disinfectant. The ammonia combines with the existing chlorine, which is called free chlorine to create chloramines.

Are chloramines new?

No. Many cities in the U. S. and Canada have used chloramines for decades. Denver, Colorado, for instance, has used chloramines since 1917.

Why is my water supplier making the change to chloramines?

Illinois American Water has decided to use chloramines for their ability to last in the distribution system, for their lack of taste and odor and for their safety. It has been shown that chloramines help deliver water to you with the lowest possible levels of Disinfection By-Products (DBPs).

What are Disinfection By-Products (DBPs)?

DBPs are chemical compounds that are formed when chlorine mixes with naturally occurring organics in water. The Environmental Protection Agency (EPA) has conducted tests, which determined that some DBPs are carcinogenic when consumed by laboratory animals in large quantities over a prolonged period of time, and are suspected carcinogens for people.

Are chloramines safe?

Yes. Chloramines have been used safely in the U. S. and Canada for many years. EPA accepts chloramines as a disinfectant and as a way to avoid DBP formation. Drinking water requires some type of disinfectant due to disease-causing organisms such as typhoid and cholera that could be carried in your drinking water. Chloraminated water is safe for bathing, drinking, cooking and all uses we have for water every day. However, there are some groups of people who need to take special care with chloraminated water: kidney dialysis patients, fish owners and industrial users.

Why do kidney dialysis patients have to take special precautions?

In the dialysis process, water comes in contact with the blood across a permeable membrane. Chloramines in that water would be toxic, just as chlorine is toxic, and must be removed from water used in kidney dialysis machines. There are two ways to do that - either by adding ascorbic acid or using granular activated carbon treatment. Medical centers that perform dialysis are responsible for purifying the water that enters the dialysis machines.

Do medical centers, hospitals, and clinics that perform kidney dialysis know about the change to chloramines?

Yes. All medical facilities have been notified of the change. All dialysis systems already pretreat their source water: some will have to modify their equipment before the change to the new type of disinfectant. If you have any doubt, please ask your physician.

What should people with home dialysis machines do to remove chloramines?

You should first check with your physician who will probably recommend the appropriate type of water treatment. Often, home dialysis service companies can make the needed modifications. But you should check with your physician to be certain. 

If chloramines are toxic, how can people and pets safely drink the water?

Chloraminated water is no different than chlorinated water for all of the normal uses we have for water, and is totally safe to drink.  The digestive process neutralizes the chloramines before they reach the bloodstream. Chloramines are only harmful when they go directly into the bloodstream - as in kidney dialysis or in a fish's gill structure.  In these instances, chloramines must be removed.  Even kidney dialysis patients can drink, cook, and bathe in chloraminated water.

Won't letting water sit for a few days remove chloramines from tank or pond water?

No. Unlike chlorine, which dissipates when water sits for a few days, chloramines may take weeks to disappear. If you don't want to use a dechloraminating chemical, the next best solution is to install a granular activated filter and allow sufficient contact time. 

If only a small amount of water is added to an aquarium or pond to make up for evaporative loss, do chloramines still have to be remove?

This will depend on the amount of water added in relation to the size of the aquarium or pond and the time period over which it's added. An alternative is to monitor for a total chlorine residual in the aquarium or pond while adding the chloraminated water rather than a free chlorine residual. For both chlorine and chloramine residuals, the total chlorine in the water used to keep fish should be kept below 0.1 mg/L. Total chlorine test kits are available from pet stores, pool supply stores and chemical supply houses.

Are both salt and fresh water fish affected by chloramines?

Chloramines will have to be removed if the water used to make salt water solution comes from a chloraminated supply. Chloramines affect salt water fish just as they effect fresh water fish. 

Can Koi assimilate chloramines unlike other fish?

No. Koi are just as susceptible to chloramines as any other fish.  

How about washing an open wound, such as a cut, with chloraminated water?

Certainly. Even large amounts of water used in cleaning a cut would have no effect because virtually no water actually enters the bloodstream that way.

Can people with kidney ailments, on low-sodium diets, or with diabetes use chloraminated water?

Yes. People with those medical problems can use chloraminated water for all purposes.

The digestive process neutralizes the chloramines before they reach the blood stream. Even kidney patients can drink and bathe in chloraminated water. 

Can pregnant women and children drink chloraminated water?

Yes. Everyone can drink water that contains chloramines.

What about people who are sensitive to chemicals?

The amount of chloramines will be no more than 4 parts per million parts of water. If you are concerned that this concentration might cause problems for you, check with your physician. The predominant type of chloramines will be monochloramine NH2Cl) and will be approximately in the ratio of 5 parts chlorine to one part ammonia-nitrogen.

Will chloramines change the pH of the water?

No. The pH of the water will remain the same as before.

What will water taste like with chloramines?

If you notice any change at all, you may find the water has less of a chlorine odor or taste

Do home water softeners remove chloramines?

Most water softeners are not designed to remove chloramines.

Does bottled water have chloramines?

It could. If the bottled water company uses water supplied by a water district that uses chloramines, then the water it provides will have chloramines in it, unless the company takes special steps to remove them.

Will chloramines affect swimming pools?

No. You will still need a free chlorine residual to retard algae and bacteria growth. The chlorine chemicals and test kits you currently use can still be used with confidence. Contact your local pool supply store for any specific questions.

Will a carbon filter remove chloramines?

Yes. However, it must contain high quality granular activated carbon and you must permit sufficient contact time.

Will reverse osmosis remove chloramines?

No. Salts can be caught by the permeable membranes but chloramines pass through easily.

Will chloramines be removed by boiling the water?

No. Boiling is not an effective method of removing chloramines from water. The only practical methods for removing chloramines from water are using a water conditioner which contains a de-chlorination chemical or by using granular activated carbon.

How do chloramines affect fish?

Chloramines are toxic to fish and must be removed from water, just as chlorine is toxic and must be removed. Chloramines affect salt-water fish just as they effect fresh water fish. You may not have had to remove chlorine from your aquarium water, however, because it disappears rapidly on its own. This is not the case with chloramines and steps should be taken to remove chloramines. Most pet stores sell de-chlorinating agents and generally have recommendations on how to use them. The chemicals used to remove chlorine should work just as well for chloramines. Several manufacturers have been adding chloramine information to the labels on their products.

How much of a de-chloraminating agent or what type of granular activated filter should be used?

Ask your pet supplier or read the instructions on the container or equipment.

What are the effects of ammonia on fish?

Ammonia can be toxic to fish, although all fish produce some ammonia as a natural byproduct. Ammonia is also released when chloramines are chemically removed. Although ammonia levels may be tolerable in individual tanks or ponds, commercial products are available at pet supply stores to remove excess ammonia. Biological filters, natural zeolites, and pH control methods are effective in reducing the toxic effects of ammonia.

Mosquito control agencies sometimes use fish to eat mosquito larvae. Will these fish be affected?

They would be affected if the water in the channels or ponds is chloraminated. Most water that runs into channels, however, would be agricultural, landscaping or storm water drainage. After water has been used for one purpose, it probably would not have enough residual chloramines to affect the fish.

Will chloraminated water used for agricultural purposes have any effect on fish in adjacent streams?

Most water which runs into streams and ponds would be agricultural, landscaping, or storm water drainage. After water has been used for one purpose, it probably would not have enough residual chloramine to affect fish.

How about using chloraminated water on ornamental plants, vegetables or fruit and nut trees? Will beneficial soil bacteria be harmed?

The small amount of chloramines should have no effect on plants of any type. Beneficial bacteria will generally be protected by the soil in which they live. Chloramines will be removed by the high chlorine demand in the soil.

For more information, visit the United States Environmental Protection Agency Chloramines page.