Frequently Asked Questions

Chloramine and Tulsa’s Drinking Water

When is the City of Tulsa making a change from chlorine to chloramine as the disinfectant used for its drinking water?

The City of Tulsa announced in June, 2010 that it is beginning an 18-month process to convert the disinfectant used in the distribution system to treat Tulsa’s drinking water from chlorine to chloramine.

Why is this change being made?

  • To meet new and stricter Environmental Protection Agency (EPA) standards going into effect in 2012 (Stage 2 Disinfectants and Disinfection Byproducts Rule), the City of Tulsa needs to change the secondary disinfectant from chlorine to chloramine to meet the drinking water standard for disinfectant byproducts.
  • After years of studying disinfection byproduct control, Tulsa’s Public Works Department has determined that chloramine, used as a secondary disinfectant in the city’s water distribution system, is the most cost-effective disinfectant method that will allow the City to comply with the new, stricter federal standards.

What exactly are chloramines?

  • Chloramine, a common alternative to chlorine, is a disinfectant used to treat drinking water. Specifically, chloramines are formed when ammonia is added to chlorine to treat drinking water.
  • The typical purpose of chloramine is to provide longer-lasting water treatment as the water moves through pipes to consumers. This is called “secondary disinfection.”

Are chloramines safe?

  • Chloramine has been used in water supplies as a disinfectant for almost 90 years, and it is currently used in almost half of the city water systems throughout the South and Southwest.
  • Chloramine has been shown to be an effective secondary disinfectant based on decades of use in the United States, Canada and Great Britain.

What other cities use chloramines in their water supplies?

  • Communities such as Oklahoma City, Sand Springs, Norman, Lawton, Dallas, Fort Worth, Arlington and Denver are just a few that have used chloramine to treat their water supplies for years.
  • Chloramine use has increased in recent years across the United States due in part to new, stricter drinking water regulations.

So will the EPA not allow the City of Tulsa to use chlorine any more?

Chlorine is still a very effective disinfectant and the City will continue to use chlorine at the water treatment plants as the primary disinfectant. But studies show that if the City continues to use chlorine as its secondary disinfectant, Tulsa’s drinking water quality will not meet the new, stricter EPA drinking water standards.

Why is chloramine a more effective secondary disinfectant than chlorine?

Chloramine is more chemically stable than chlorine, which makes it longer lasting and a more effective secondary disinfectant than chlorine because it doesn’t break down as quickly in water pipes.

When will the Tulsa conversion take place?

  • The 18-month conversion to chloramine is expected to be completed by fall 2011.
  • The conversion project will begin immediately with engineering studies conducted by CH2M HILL, an international engineering firm with offices here in Tulsa.

How will the change to chloramine affect Tulsa water?

  • The change will reduce the accumulation of undesired byproducts and help Tulsa meet all of the EPA’s primary drinking water quality standards.
  • A noticeable improvement may occur in the odor and taste of Tulsa’s drinking water.
  • No noticeable change in service to residents is anticipated.

Will anyone need to change how they use Tulsa’s water?

  • Kidney dialysis patients and renal center staff must be attentive when testing water during and after the transition. The city of Tulsa will work closely with these water customers to ensure they have the information they need to make the conversion and that treatment centers and patients are prepared for the change prior to the conversion.
  • Fish owners may need to change the way they de-chlorinate the water in fish tanks and ponds.

How will the City pay for the conversion from chlorine to chloramine?

The operation, maintenance and capital improvements required to provide water to the City of Tulsa are funded entirely by water rates. The City of Tulsa has been studying and evaluating this change for many years, and funding for this project will be provided through the TMUA capital budget. Money for the engineering study and design was provided in the FY10 water capital budget. The remaining funding for the installation of the required improvements will be provided in the FY11 water budget.

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