Cary/Apex Water Treatment Facility to Begin Annual Disinfection Process Change

• In accordance with state and federal recommendations, the Cary/Apex Water Treatment Facility will temporarily stop adding ammonia to its water treatment disinfection process beginning Friday, February 27, 2026.
• Citizens who use water for kidney dialysis machines, fish aquariums, or other chlorine-sensitive uses should be aware that varying concentrations of chlorine and ammonia may be present at the beginning and end of this process as treated water moves through the system.
• This annual process is recommended for municipal water systems and is being conducted in conjunction with other municipalities in the area.

Cary, NC - In accordance with state and federal recommendations, the Cary/Apex Water Treatment Facility will temporarily stop adding ammonia to its water treatment disinfection process beginning Friday, February 27, 2026. Citizens who use water for kidney dialysis machines, fish aquariums or other chlorine-sensitive uses should be aware that water may contain chlorine, or a mixture of chlorine and ammonia, at the beginning and end of the process. This annual process is recommended for municipal water systems and is being conducted in conjunction with other municipalities in the area. The water treatment facility will resume adding ammonia to the water treatment process on Monday, April 6, 2026. The Cary/Apex Plant provides treated water to Cary, Apex, Morrisville, the Raleigh-Durham International Airport and the Wake County portion of Research Triangle Park.

To help keep drinking water safe, Cary uses a combination of chlorine and ammonia to disinfect water. The State of North Carolina recommends all water systems with the chlorine/ammonia process to cleanse their systems annually by switching to free chlorine and flushing the systems.

"This annual disinfectant conversion is a standard and important practice that helps us maintain the long-term health of our water distribution system," said Utilities Director Jamie Revels. "While most residents will notice a minor increase in chlorine odor, in some cases, water may appear slightly discolored." Revels noted that any minor changes are temporary and a normal part of the annual process.

Primary Contacts

If you have specific questions, visit carync.gov/311, dial 311 anywhere in Cary, (919) 469-4000 outside Town limits, or email [email protected].

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