10/16/2026
Did you know air in a water distributing system can reduce the effectiveness of chlorine and your chlorine residual? The Hydrant Air eXhaust valve is simple and effective way to get air out of our water pipes.
https://smpl.is/akq03
Details:
Yes, air in a water distribution system can directly impact chlorine levels, causing residual chlorine to deplete faster and altering its effectiveness as a disinfectant.
The interaction between trapped air and chlorine occurs through several mechanisms:
Off-Gassing: Chlorine is volatile. When air bubbles are introduced into a chlorinated water system—or when water is exposed to trapped pockets of air in high points of the piping—the chlorine begins to transform from a liquid to a gas and evaporates into the air pocket. This loss reduces the overall chlorine residual.
Increased Water Age & Stagnation: Accumulated air blocks the smooth flow of water. This restriction creates dead-end zones and pockets of stagnant, aged water. In aged water, chlorine has more time to react with organic matter and pipe walls, causing the residual to decay much more rapidly. [1, 2, 3]
pH Level Shifts: Aeration (the continuous mixing of air and water) releases carbon dioxide gas, which generally increases the water's pH. When pH rises, chlorine shifts its molecular balance, transforming into hypochlorite ions (\(OCl^{-}\)) rather than hypochlorous acid (\(HOCl\)). Because hypochlorous acid is the much more potent and destructive form of disinfectant, this pH shift renders the remaining chlorine less effective at killing bacteria.
