Common water complaints

Unfortunately, there is nothing we can do to the drinking water supply to prevent the growth of biofilms within customer’s properties.

The best way to prevent growth is to improve ventilation, to allow these damp areas in kitchens and bathrooms to dry rapidly, and the only way to keep on top of them is regular cleaning of all affected surfaces.

It is also important to reduce the amount of food available for the bacteria and fungi. Food sources can include shampoo, soaps, propellants from hairspray and deodorants.

Black slime associated with tap fittings can be removed by cleaning the inside of the tap or around the base of the tap with a small brush dipped in a mild solution of bleach.

The tap should be thoroughly flushed immediately afterwards. If a tap has a plastic insert or any other detachable fitting attached to it, the fitting should be regularly removed, cleaned and disinfected.

All water distribution networks are susceptible to biofilm growth. Biofilms are kept to a minimum in the distribution network (prior to entering customer’s properties) via the following:

• maintenance of adequate residual chlorine levels throughout the distribution system
• comprehensive networks maintenance programme, including regular mains flushing and pipe replacement
• service reservoir maintenance, including regular cleaning programme
• adequate filtration and disinfection of raw water sources, prior to release from the water treatment works

The efficacy of the above is monitored through our comprehensive sampling regime at water treatment works, service reservoirs and customer’s taps. In addition to this, we also sample mains following renewals, repairs and shutdowns. All of these samples are analysed for the presence of coliforms, a key indicator to the presence of pathogenic microorganisms.

We add chlorine at our water treatment works in very small concentrations to protect your drinking water against bacterial growth. Some consumers who receive a supply shortly after it leaves the water treatment works may notice a stronger smell and taste of chlorine in their drinking water. Those at the end of the supply system are unlikely to be affected as the chlorine is absorbed as it makes its way through the mains system.

You may notice that the taste or smell of chlorine is stronger at different times of the day; don't worry, this is perfectly normal and could be due to:

• your distance from the treatment works
• the time the water spends travelling to your house
• water temperature
• where your water is sourced from
• time of day – first thing in the morning and early evening more people are using the water
• water travelling quickly through the mains, for example, when a main has burst in your area or emergency services have drawn water from a hydrant

Putting an uncovered jug of water in the fridge for a few hours will reduce the taste and smell.

Filters can be purchased to remove chlorine. These vary in price and quality and we recommend you check and clean them regularly. Keep in mind that it is better to have water with chlorine in it, as at least this way you are protected from bacteria and the water is safe to drink.

Chlorine can react with plastic or rubber in your plumbing, causing disinfectant, TCP and metallic tastes and smells. These materials can be found in kettles, appliance hoses and tap washers. The tastes aren't harmful although, we agree, they don't taste very nice!

If you notice this taste or smell in hot drinks you can try boiling water in a saucepan to see if your kettle is the cause.

If it's not the kettle, one of the hoses connecting pipework and appliances could be causing the taste. You can try disconnecting your washing machine and dishwasher hoses overnight, and changing tap washers to an approved type. 

If you don't think it is a hose or the kettle causing the problem or if you've had new taps fitted recently, it may be one of the tap washers causing the taste. If the water tastes unpleasant at all the taps check the washer on your internal stop tap.

Spillages of fuels, oils and solvents can seep through plastic water pipes and contaminate your drinking water, which can be extremely harmful to your health.

There are a few simple steps you can take to protect your drinking water. We recommend that you:

• check your oil tank for signs of leakage especially older metal ones.
• take care when using fuels and chemicals around your home and clean up any spillages quickly and dispose of waste correctly.

If you think your water supply may have been affected by a fuel or chemical spill contact us immediately and we can investigate.

In the Isle of Man there are occasional incidents of discoloured water. The most common reason for discoloured water on the Island is the disturbance of iron and manganese deposits that are present in the water mains. This can happen when water changes direction or speed. Changes in flow can occur for many reasons:

• burst water main
• opening or closing of valves
• bringing a water main back into use after repairs
• having to move water from one area to another to cope with changes in demand
• heavy use in one area such as the use of water for fire fighting

These problems can turn the water orange, brown, black or grey. Excess air in the system may also cause the water to appear white.

Over time deposits build up in the Island's water mains. The principle causes for this are as follows:

• iron and manganese are present in the source water; inadequate treatment in the past through the decommissioned treatment plants has resulted in iron, manganese and other deposits forming in the mains
• many of the water mains are cast iron and the older ones are unlined and have corroded. The iron corrosion particles (rust) become loose and can be carried through the network by the water

We deal with removal of deposits in the mains by lining or replacing the affected mains. 

If the discolouration is due to mains deposits, these are mostly iron and manganese and, as such, are not likely to be harmful to your health. However, you may not wish to drink the water or give it to your family because it looks or tastes unpleasant.

White water caused by excess air will clear from a glass of freshly poured water and is not something to worry about. Sometimes a white scum may form around the side of the glass. This is due to a phenomenon known as surface tension, which traps some of the tiny bubbles at the waters surface. The water is not likely to be harmful to your health. However, if the problem persists please contact us.

If your washing has been discoloured because of the water, repeat the wash when the water is not discoloured without adding fabric softener.

If your water remains discoloured then please get in touch with us.