You can also find tips and advice in our short films on
WaterSafe’s YouTube channel.
On rare occasions tap water may become discoloured, appear cloudy, or appear to have very small particles in it.
Discolouration can range from a light straw yellow colour to dark brown. It can be caused by a number of things including:
Naturally occurring substances
Disturbance of mains deposits
Corrosion of service pipes
Internal plumbing issues.
In most cases discoloured water is not harmful and can be cleared by running the first incoming cold water tap (usually in the kitchen) at a trickle until it clears.
Very occasionally water suppliers receive calls about "tiny particles" or "bits" in their tap water. This can be caused by:
Planned or unplanned work to the water supply network which causes sediment in the pipes to shift (quite often this is a dark red, brown colour)
Small dark grey or black particles can occasionally be caused if your pipework is made from lead. This is most likely if your house was built before 1970.
For more information, please contact your water supplier.
Please note: If your water is blue, pink, green or any other colour not described above, please do not drink the water or use it for cooking purposes until you have sought advice from your water supplier.
Blue or green looking water is often due to the presence of new copper pipework, either in new houses or where new pipework has been installed in older properties. This is because these new copper pipes are settling in.
To help prevent this from happening, take the following steps:
Only use lead-free flux
Flush through new pipework thorougly
Drain down plumbing systems which are not used immediately after installation.
Blue water can also be caused by poorly installed toilet cisterns, which allow water from the cisterns to siphon back into the internal plumbing.
For information about how to check your toilet cistern please visit the WRAS website.
If your water is blue please do not drink the water or use it for cooking until you have sought advice from your water supplier.
Sometimes water can look milky or cloudy because it contains tiny bubbles of air. Air is always in water, but it can be more obvious after it has travelled through the mains, if there is a burst mains pipe or if a faulty plumbing fitting has been used.
As well as the change in how it looks, you may also notice knocking or banging noises coming from the internal plumbing.
To check if this is the problem, run a glass of water and allow it to stand for a few moments - the cloudiness should clear from bottom to top. To help fix this, you can try running the cold water tap at the first point of entry in to the property (closest to the internal stop tap) on a slow steady flow. While the tap is running, turn the internal stop tap on/off 4-6 times to help release the air from the pipes.
Cloudy water caused by tiny air bubbles in the water is not harmful to health.
If you've tried this but are still concerned, or you'd like more advice you should contact your water supplier.
In this video from Wessex Water, you can learn more about issues with the appearance of your water, as well as tips for how to improve it.