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Below is a list of frequently asked questions that the Chartered Institute of Plumbing & Heating Engineering (CIPHE), the professional body for the plumbing & heating industry, has devised to alleviate many concerns that members of the public may have following flooding.

I filled up the bath and also pans of water, but how long will it last to be safe to drink?

CIPHE would recommend that you boil any open stored water prior to consumption. Storing water in a clean sterile container that has a close fitting lid (not airtight, but excludes light) and is made from a material that will not contaminate the water itself. It could last for a number of days if kept cool.

How can I flush the WC?

It may be worth considering conserving any stored water and flush WCs by utilising the floodwater or rainwater, using a suitable container.

If my home is flooded should I turn off the boiler straight away?

If your home is flooded the electricity to the property should be isolated immediately, this would turn off the boiler. When the flooding has subsided the complete electrical installation should be checked by a competent electrician, and the boiler isolated until it is checked by a Gas Safe/ OFTEC / HETAS registered service engineer.

When the flooding has subsided how difficult will it be to get my boiler working again?

If the boiler has come into contact with floodwater it must be checked by a Gas Safe/ OFTEC / HETAS registered service engineer. If any electrical components within the boiler have been submerged they will probably need replacing. Any insulation with the combustion chamber should be checked and replaced if damaged.

I had my water disconnected. When it comes back on will it cause any damage to my Combi boiler?

No, as long as the heating system has no leaks and system pressure is around 1 bar (sealed systems only), the boiler should work normally. However, if when reconnected the mains water is very dirty, the boiler’s built in filter may require cleaning by a service engineer. The chances of this can be reduced by running the first cold water tap in the property (usually in the kitchen), until it runs clear.

I have no water now but when the water does come back on, will it be safe to drink straight away?

We would recommend that your plumbing system should be flushed out to eradicate any debris and any possible contaminants. If you are concerned that there has been further contamination of your system, those competent to do so should disinfect the system. If after flushing, you still have concerns regarding the colour of the water coming out of the tap, for instance it is a milky colour, this is probably due to turbulence in the main causing aeration of the water. Leave the water to settle in a glass, whereupon it should clear after a couple of seconds.

Where can I get further information?

The CIPHE website provides Databyte fact sheets on flushing and disinfection, in addition to information on water borne diseases associated with flood water such as weils disease and cryptosporidium. Your Water Company will also be able to give you advice.

Can I use my dishwasher after the flood has subsided?

If you have any concerns over the quality of the water coming from the mains you should not use a dishwasher.

Who should I contact to find a professional plumber or heating engineer?

The CIPHE is the UK’s professional and technical body and has around 9,000 members who abide by a code of professional standards, this includes Gas Safe/ OFTEC / HETAS registered operatives. All have ID cards and members can be recognised by the CIPHE logo. Contact details of Registered Plumbers in your local area can be found using a unique postcode search facility on our website or by calling the CIPHE head office on 01708-472791

CIPHE TOP TIP! Don’t forget to turn off your taps and water outlets if you have no water supply, to prevent the possible back siphonage of contaminated flood water into your plumbing system. In addition, when the water is turned on again you do not want to cause further problems with overflowing water.