There are a number of reasons why your water supply might have a different taste or smell.  They have simple explanations and are no cause for alarm.

Water is classified according to its source. Groundwater comes from wells and boreholes underground in chalk or sandstone rock.  Surface water comes from rivers and reservoirs.  About 70 per cent of water supplied in our region comes from underground sources.

The source of the water will determine the degree of naturally occurring minerals that can give rise to slightly different tastes.  Sometimes we change the source of your water supply and you may notice a different taste.

Surface water may sometimes have a flat, earthy taste and, in the warmer summer months, a distinctive smell.  This is often caused by the growth of algae on rivers and reservoirs.  Treatment is in place at water supply works to reduce taste and odour associated with surface water.

Click on the headings below for more information about why your water may have a particular taste or smell: 

1. Musty or earthy tastes or smells

   • In the past, various organic materials have been used in domestic plumbing systems, such as grease and fibre washers.  Bacteria can grow in these if the pipework is warm and rarely has water flowing through it. This can cause musty or earthy tastes or smells.  If this problem persists cleaning and disinfecting the plumbing system may be necessary.

2. Metallic tastes

   • If domestic pipes or fittings containing copper or zinc begin to corrode it may increase the concentration of these metals in the water and produce metallic tastes.  

     Metallic tastes can be reduced by running water into a bowl for a short period of time after water has been standing in the pipework for a prolonged period (e.g. overnight).  Do not waste the water - use it on your houseplants or in the garden.

3. Chlorine, antiseptic or TCP-like taste or smell

   • Chlorine is used to treat water to make sure it is safe to drink. Only very small amounts are used, but, on rare occasions, a smell or taste may develop when the water flows through the water mains or while it is stored in underground service reservoirs.

      Unusual flavours may also happen because the chlorine reacts with household fittings. Common examples are anti-splash devices on taps. A sure test is to ask neighbours if they are having the same problem.

     These tastes may vary because they depend on how long the item has been in contact with the water. A good example is a TCP-like taste in the first cup of tea in the morning, perhaps caused by a faulty tap washer which has not been used overnight. The short-term remedy is to run the tap before you use it and to fit a new washer as soon as possible.

     Leaving a jug of water in the fridge overnight will remove any chlorine taste but don't store it for more than 24 hours.

4. Gas or fishy smells

   • These occasionally occur in the hot water system. Dead animals or birds falling into the roof tank are a frequent cause so it is important to protect the tanks with an effective cover.  If this problem persists, cleaning and disinfecting the plumbing system may be necessary.
      

5. Lead pencil or graphite taste

   • A variety of anti-oxidants are used in the manufacture of some types of plastic pipes. The only way to remove this taste is to replace the pipes.
      

6. Miscellaneous

   • Some plastic pipes may be made of material that lets through substances which may affect the taste or smell of your water.  Do not lay plastic pipes close to fuels, bituminous materials or floor sealants.
     
     The rubber or plastic hoses to dishwashers need to be connected to the water system via a non-return valve.  

     Looking after water in your home.