In the winter months, many people notice a milky or cloudy appearance to their tap water. This is caused by air bubbles trapped in the water. It is harmless and will disappear on its own if left out for a few minutes.
This phenomenon occurs more often in the winter due to the colder temperatures. Cold water can trap and hold larger amounts of dissolved oxygen than warm water. Most of our water comes from the Mississippi River, which then travels through a chain of lakes before arriving at our plant. This surface water is much colder in the winter months. Not only is the water cold coming into our treatment plant, but the pipes that deliver the water to your home from the plant are cold as well.
In addition, water in the pipe is under pressure. That pressure makes it impossible for the air in the water to get out while it is still in the pipes. Once it comes out of your faucet, it is no longer pressurized and the air begins to escape, like opening a pop can. The warmer room temperature also contributes to the release of air bubbles, as warmer water cannot hold as much air. As the air escapes and the bubbles rise to the surface, it looks cloudy. Sometimes there are enough bubbles that it looks like there is debris or small particles swirling around your glass. As the air dissipates, the water clears from the bottom of the glass to the top. Bubbles may attach to the sides of the glass as the water clears.
Trapping air is a natural phenomenon associated with cold water, and it does not affect water quality. If you have questions or concerns, you can always call our office at 651-266-6350.