Cloudy or milky-looking water from a faucet is often caused by dissolved air in the water supply. This phenomenon, known as entrained air, occurs when air becomes trapped in the water, giving it a cloudy appearance. The water is generally safe to drink, and the cloudiness typically dissipates as the air escapes.
The presence of dissolved air is often harmless, and it is more common in colder months when the water is colder and can hold more air. Changes in pressure within the water distribution system can also contribute to this temporary cloudiness. Historically, concern arose due to the potential association with more serious issues, but generally, it’s a readily explainable and temporary cosmetic problem.