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- Free Chlorine Conversion 2023
Free Chlorine Conversion 2023
There will be a temporary change in the way we treat your water.
The city will temporarily convert the disinfectant used in the water treatment process from chloramine to free chlorine. The duration of the free chlorine conversion will be approximately 30 days and will begin on April 4, 2023. The city will return to chloramine disinfection on May 2, 2023.
This change only applies to the main city water system that receives treated surface water. It will not affect customers in Riverpark, Greatwood, or New Territory, as those water systems are independent and already on free chlorine at all times.
What to expect during the temporary change
Generally, there are no noticeable changes in water quality as a result of this temporary conversion. However, some individuals may notice taste and odor changes and a slight discoloration to the water, primarily during the transition period. Noticeable water quality changes associated with conversions are normally short-lived and are not public health risks.
Is the water safe during this change?
The water will be safe for people and animals to drink, for cooking and bathing, watering the garden, and for all other common uses.
However, people and businesses that normally take special precautions to remove chloramines from tap water, such as dialysis centers, medical facilities, and aquatic pet owners, should confirm whether pretreatment adjustments are necessary during the temporary switch from chloramines to free chlorine.
At the conclusion of the conversion period, which will occur on May 2, the city of Sugar Land will convert its disinfection process back to chloramines.
Why is this necessary?
Sugar Land’s main water system currently uses chloramines (a combination of free chlorine and ammonia) to disinfect its drinking water supply prior to customer distribution. This is a reliable disinfection process that has been recommended by the Texas Commission on Environmental Quality (TCEQ) for systems treating surface water such as the city’s main water system.
It is standard industry practice to periodically convert chloramines back to free chlorine to improve and maintain the highest water quality standards. In addition, the Environmental Protection Agency (EPA) and the TCEQ support this process as a necessary and effective measure for maintaining water quality.
The city will implement directional flushing, combined with routine water quality monitoring to maintain the highest water quality for customers during the conversion.
Water quality data during the conversion
During the chlorine conversion, city staff will test samples throughout the main water system for free chlorine. The city's target free chlorine residual is between 0.5 to 3.5 milligrams per liter(mg/L).
Chlorine Levels Map Coming Soon!
A map that will enable you to check current chlorine levels in your area is coming soon.
Frequently Asked Questions and Answers
- What is the purpose and/or benefit of a free chlorine conversion?
The city of Sugar Land’s Main water system uses chloramines for disinfection. Chloramines are a better long-term choice for systems on surface water because they produce lower levels of disinfectant byproducts like trihalomethanes when chlorine mixes with natural organic substances in water. However, prolonged use of chloramine coupled with other factors that can affect water quality, such as high temperatures, may result in the growth and/or persistence of organic matter within the pipes of the distribution system. Though harmless when consumed by humans, this organic matter can introduce unwanted taste and odor, and hinder the ability to maintain an adequate disinfectant residual. A temporary conversion to free chlorine, partnered with flushing activities, clears distribution pipes of this organic matter and improves the quality of your water overall.
- How long will the free chlorine conversion last?
The duration of the free chlorine conversion will be just under 30 days. The conversion will begin on April 4, 2023, and the City will return to chloramine disinfection on May 2, 2023.
- What is chloramine?
Chloramine is a disinfectant used in drinking water to inactivate bacteria and viruses. It is typically used for water systems sourced from surface water. The city of Sugar Land uses chloramine as a disinfectant in its Main water system. Refer to the service area map.
- What is free chlorine?
Free chlorine is a disinfectant used in drinking water to inactivate bacteria and viruses. It is typically used for water systems sourced from groundwater. The City of Sugar Land uses free chlorine as a disinfectant in its RiverPark, Greatwood, and New Territory water systems. Refer to the service area map.
- What is a free chlorine conversion?
A free chlorine conversion is a process by which a water system temporarily switches its disinfection process from chloramines (a combination of chlorine and ammonia) to free chlorine (chlorine only) in order to improve the long-term quality of its drinking water.
- Are free chlorine conversions a common practice among water systems?
Yes. Free chlorine conversions are a common industry practice for preventative maintenance in drinking water distribution systems. Many utilities throughout the state and country that use chloramines for their primary distribution disinfectant periodically convert back to free chlorine to improve and maintain the highest water quality standards. The Environmental Protection Agency (EPA) and the Texas Commission on Environmental Quality (TCEQ) endorse and support this procedure.
Additional educational resources
Hear from the H2O Pros
Back in 2021, Public Works Director Brian Butscher (formerly Deputy Director) and Surface Water Plant Manager John Bailey explained the city's temporary conversion of the disinfectant used in the water treatment process from chloramine to free chlorine.
This video was recorded in 2021, however, the discussion and information provided is relevant to the 2023's free chlorine conversion process.