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Temporary Change in Disinfectant
What Does This Mean for Prosper Residents?
Water Maintenance is from March 3 to March 31, 2025. Residents of the Town of Prosper receive their water supply from the North Texas Municipal Water District (NTMWD). You might observe a more noticeable chlorine scent in your tap water. Rest assured that the water is still safe for both use and consumption.
To uphold public health and guarantee the safety of water distributed to 2 million North Texans, the NTMWD employs dependable and effective disinfection methods. As a vital precaution to preserve the purity of Prosper's water, the NTMWD introduces an annual, temporary disinfection adjustment spanning a 2,200-square-mile service region, crucial for ensuring the water's safety on its journey to your faucet.
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 ensures water remains disinfected and safe for drinking as it travels long distances through pipes to the tap. Most of the year, NTMWD disinfects its water using a combination of ozone and chlorine (first step) and then chloramine, which combines 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 before distribution may utilize several 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 of 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, NTMWD temporarily changes the disinfectant used in the second water treatment step for about one month. 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 to the tap as it travels long distances. Chlorine levels in the water are consistent with year-round operations. However, ammonia's discontinuation can make chlorine's presence 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 chloramine water providers 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, which is consistent with normal year-round operations.