2020 Water Maintenance

What Does This Mean for Little Elm residents? 

As Little Elm gets its water from the NTMWD, you may notice a more distinct chlorine smell to your tap water, however, water remains safe for use and consumption.

Even at very low concentrations, some people may be more sensitive to taste, smell, and skin contact with chlorine. Here are some simple steps to help minimize those effects:

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Download the NTMWD Spring 2019 Maintenance information here

Common FAQs

What is NTMWD’s routine water treatment process?

Disinfection of water is typically a two-step process. The first step is to inactivate or kill microorganisms, such as bacteria, parasites and viruses, during treatment. The second step makes sure water remains disinfected and safe for drinking as it travels long distances through pipes all the way to the tap. Most of the year, NTMWD disinfects its water using a combination of ozone and chlorine (first step) and then chloramine, which is the combination of ammonia and chlorine (second step).

Why do you use chlorine/chloramine to disinfect water?

Chlorine is the most widely used water disinfectant in the world. Only chlorine-based disinfectants (including chloramine) are approved by the U.S. Environmental Protection Agency (EPA) for the second step of water disinfection. According to the Texas Commission on Environmental Quality (TCEQ): “Treatment prior to distribution may utilize a number of different disinfectants, but a public water system is required to use either chlorine or chloramine in the distribution system.”

EPA requires water treatment facilities to maintain a minimum chlorine level of 0.5 milligrams per liter (mg/l)—or parts per million (ppm)—during normal operations and a maximum running average 0.5 of 4 mg/l (or 4 ppm). These levels are safe for use or consumption.

Why is the temporary change in disinfectant necessary?

Each spring for about one month, NTMWD temporarily changes the disinfectant used in the second step of water treatment. This is necessary to help maintain the system and high water quality year-round. During this time, ammonia is temporarily suspended and only chlorine is used to maintain water disinfection from the time it leaves the treatment plant as it travels long distances to the tap. Chlorine levels in the water are consistent with year-round operations. However, the discontinuation of ammonia can make the presence of chlorine more noticeable. Cities may help with this process by flushing water out of fire hydrants during this time, which helps move the chlorine through the system faster. The EPA estimates up to 40 percent of water providers who use chloramine conduct this process.

Does NTMWD add more chlorine during this period?

No, test results verified by the TCEQ show chlorine levels during the temporary change in the disinfectant process are consistent with normal year-round operations.

Get more answers here




Why do you use chlorine/chloramine to disinfect water?

Chlorine is the most widely used water disinfectant in the world. Only chlorine-based disinfectants (including chloramine) are approved by the U.S. Environmental Protection Agency (EPA) for the second step of water disinfection. According to the Texas Commission on Environmental Quality (TCEQ): “Treatment prior to distribution may utilize a number of different disinfectants, but a public water system is required to use either chlorine or chloramine in the distribution system.”


EPA requires water treatment facilities to maintain a minimum chlorine level of 0.5 milligrams per liter (mg/l)—or parts per million (ppm)—during normal operations and a maximum running average 0.5 of 4 mg/l (or 4 ppm). These levels are safe for use or consumption.