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About Chloramines

Chloramines are disinfectants added to the water for public health protection and are most commonly formed when ammonia is added to chlorine to treat drinking water. Chloramines provide long-lasting protection, as chloramines are more stable than free chlorine.

There are different types of chloramines, including monochloramine, dichloramine, trichloramine and organic chloramine. Monochloramine is the most common form used to disinfect drinking water and is the form that will be used in Tulsa's water distribution system.

The Environmental Protection Agency (EPA) approves the use of chloramines as a disinfectant in drinking water. The maximum concentration of chloramine allowed in drinking water is 4 ppm (mg/l).

Chloramine History and Usage

Chloramine has a long history of effective use in city water treatment systems. Here are a few facts:

  • Chloramine has been used as a disinfectant in water systems since 1917 - more than 90 years (chlorine has been in use since 1908).
  • Chloramine is currently used by approximately 29% of community water systems. Due to the implementation of the EPA's stricter D/DBP2 standards in 2012, it's projected that a large number of other cities will be making similar conversions to meet the new standards and that approximately 55% of U.S. surface water systems will be using chloramine as a disinfectant.
  • The EPA has determined that chloramine is more stable than chlorine in the distribution system.
  • Chloramine is effective for controlling bacterial growth.
  • Chloramine forms lower levels of regulated disinfection byproducts.