Cloudy water is caused by tiny air bubbles in the water which make it appear white. They’re not harmful and quickly clear, rising from the bottom of the glass upwards.

Depending on the length of time you have been affected, the cause will be one of two things. 

  • if the cloudy water has been present for a few hours or days, it’s likely to be due to something which has happened in the water mains 
  • if the cloudy water has been present for longer, a few weeks or months, it’s likely to be caused by something inside your property.

Tap water that’s been cloudy for a few hours or days

Quick check list

My tap water: 

  • looks bubbly, cloudy or white
  • clears from the bottom upwards if I fill a glass of water
  • clears after I run the tap for a while
  • may have been turned off recently
  • may be a lower pressure than normal
  • is cloudy at all taps in my house
  • is cloudy in my house and at my neighbour’s.

What causes it?

We may have been working on your water mains network, perhaps fixing a burst main, and a pocket of air has become trapped and dissolved into the water. If this is the reason, it’s normally short- lived and shouldn’t last more than 24 hours.

What can I do?

As the cloudy water’s already in the pipe, you need to let it work its way through the system. 

  • Try running the taps for 30 minutes or more
  • Check out In Your Area to see if there’s been any activity in your neighbourhood
  • If it’s longer than 24 hours, we may need to flush the water mains to help it along its way. Give us a call and we’ll endeavour to fix the problem.
  • Sometimes internal plumbing can cause cloudy water, see below for more information.

Have you flushed your taps to remove cloudy water? If you’re on a meter call us and we’ll give you a £2 flushing credit towards your next bill - this equates to the cost of filling five bathtubs. If you run off any water from your taps, don’t waste it, collect and use for watering houseplants or in the garden. 

Tap water that’s been cloudy for a few weeks or months

Quick check list 

My tap water: 

  • looks bubbly, cloudy or white
  • clears from the bottom upwards if I fill a glass of water
  • looks clearer after I run the tap for a few seconds
  • runs slightly warm at first
  • is only cloudy at one tap
  • is cloudy in my house but ok at my neighbour’s.

What causes it?

Heat from hot water pipes or boilers can sometimes heat up your cold water and make it look cloudy. This is why when you first run the water, it is sometimes warm. Leaving the stop tap or another valve partially  shut may also cause the water to be cloudy.

What can I do?

Sometimes a quick plumbing check can solve the problem:

  • lag your pipes to prevent cold water being warmed by hot pipes
  • if there’s cloudy water from all taps, ensure your internal and external stop taps are both fully open
  • if only one tap’s affected, check your isolation valve under the sink is fully open
  • if you still have trouble fixing the problem, get some advice from an Approved Plumber
  • If you run off any water from your taps, don’t waste it, collect and use for watering houseplants or in the garden. Still stuck? Try our self diagnosis tool to help solve the problem
  • If you’re a business customer, contact your provider for more information.