White discolouration in water can be caused by trapped air and it is completely harmless. Air can occur in your water supply following repair work on the distribution network, by a pocket of air becoming trapped in the internal domestic pipe work during interruptions to your water supply.
Aerated water has a cloudy or milky white appearance. To confirm the cloudiness is caused by trapped air, fill a glass of water from the cold tap at the kitchen sink and watch to see if it clears from the bottom of the glass upwards. It can take up to 10 minutes to clear. Air trapped in the mains pipe should clear within 2 to 3 hours after works are completed.
