November 7, 2014

Recently, the city has received a number of phone calls reporting water that appears cloudy or milky. Do not be alarmed; the water is safe to drink. Sometimes water fresh from the tap can appear cloudy. Within a minute or two, the cloudiness rises toward the top of a glass and before long the whole glass is crystal clear. This is caused by excess oxygen escaping from the water. Changes in water temperature and pressure can cause the oxygen dissolved in it to reach a “supersaturated” state, where there is more oxygen in the water than it can hold. When the water passes through a faucet, the disturbance is enough to knock the oxygen out of the water, forming microscopic bubbles. The bubbles are so tiny that it takes them a long time to rise up through the water. No harm will come from using oxygenated water and you need not take any corrective action if you experience it.

Other events that can increase water velocity include: hydrant use by firefighters, main breaks, hydrant maintenance, and water or street cleaning trucks filling their tanks at a hydrant. If you happen to turn on your cold water right after such an event, you may draw some of the stirred-up water into your pipes. We welcome your calls if you have any concerns about cloudy water or if your water remains cloudy for an extended period of time.