It may surprise you to hear this, but there is actually no such thing as completely clean drinking water; at least not from our taps in any case. Just like the air we breathe and the food we eat, tap water is not 100% sterile and never will be. Do not fear, this does not mean that our drinking water is dangerous; it is of course free from pathogens and all other microorganisms that are capable of causing disease. But tap water is never going to be completely clean – despite how clean your taps are. Why is this?
Chemistry in the Pipes
At the treatment plant, water is treated in order to remove any pathogens and anything else present that is hazardous to human health. Our water is disinfected before eventually leaving the treatment works into the water pipe network. Before leaving the plant works, a tiny residual amount of chlorine is kept in the water in order to maintain its quality whilst it makes its way through our vast network of water mains and pipework. It is within these pipes where the water begins to pick up bacteria and all sorts of biological life.
In fact, more chemistry happens within the pipes than it does at the actual treatment plant. Think about it – there are literally millions of miles of pipework underground that are bound to become dirty over time. It is virtually impossible to clean and maintain every single pipe in the network at the same time; so therefore we have to expect some loss of water quality between the treatment works and our homes.
So whilst we know that tap water is never 100% clean, it’s also useful to know that brown water is actually usually harmless. Yes that’s right, brown water or any form of water discolouration is often caused by something extremely simple and relatively safe. Discoloration may be caused by a number of things, such as naturally occurring substances found in the raw H2O used to produce drinking water. Water from various sources can contain higher levels of iron, manganese or other organic materials which may give a brown or yellow tint to drinking water. Discolouration may also be caused by:
Mains deposits – over long periods of time natural deposits of manganese and iron can build up within our water pipe network. Discolouration is caused when these deposits are disturbed and re-suspended into the water flow. This is usually a temporary issue and is solved by running the tap for an extended period of time.
Pipe corrosion – over time our cast iron pipes begin to rust and corrode away. When rust is introduced to our drinking water it can give it an orange-brown tint. Sometimes the service pipes which connect our houses to the water mains in the street can corrode too; flakes of dark material could indicate that your service pipes are made of lead and are beginning to corrode.
Air in the water – air can often become trapped under pressure in the pipe network, causing the water to have a milky white appearance. This can happen following the repair of fractured water mains and can be easily remedied by running the tap for a few minutes until the air escapes.
Better to be Safe than Sorry
These are just a few common reasons why you may be experiencing water discolouration, but there are many more hazardous reasons too. If your water seems dirtier than usual and none of the descriptions/recommendations above accurately cover what you are experiencing; then make sure to contact your water provided and let them know what is happening. Remember, water is never 100% sterile but that does not mean you should drink absolutely anything! If you’re water is blue, green, pink or any other colour other than described above – contact your water provider immediately and refrain from drinking any of it! If in doubt – always ask! It is better to be safe than sorry!