A woman driven potty by a sewage block is all cisterns go with a campaign for better education over what can be flushed down the loo.

Roz Colls returned home from holiday last week to discover the drains in her home and garden blocked up with sewage and found most of Nightingale Road and Hanworth Road was affected.

She said: “There were nappies, sanitary towels. One neighbour even said they put dead fish down.

“Our drains had got right to the top. Had this not been cleared we would have had sewage come out and into our homes. It’s horrendous.”

After speaking to her neighbours, Mrs Colls realised many people did not know what could be put down the toilet.

She suggested Thames Water included diagrams on customers’ bills to help them, as is done by the council for recycling, which could avoid costs of clearing blockages being passed on to customers via their bills.

She said: “Thames Water should be educating people because I think so many people don’t realise.

“This is costing people money, us as the rate payer, so we are not helping ourselves. It is making money out of us blocking our drains.

“Maybe if we could stop people blocking drains we could avoid increases in bills."

Thames Water spends £1m clearing nearly 7,000 blockages from its 109,000km of sewers each month. Half of these are caused by items that should not be flushed, including food fat and wet wipes.

Each year, 7,000 Thames Water customers’ gardens and 1,000 homes flood with sewage, with half of these incidents the result of wrongly flushed items.

A 15-tonne blockage, composed of enough fat and wet wipes to fill a double-decker bus, was cleared from a Kingston sewage pipe last month.

Thames Water said the blockage, which was dubbed a “fatberg”, was the biggest it had ever encountered.

Of the latest blockage, a Thames Water spokesman said: “The blockage was caused by a build-up of fat and wetwipes, that had hardened into a ‘fatberg’.

“We cleared the blockage and will be returning to monitor the sewers and make sure they are working as they should.

“Wet wipes and cooking fat should never be put into the sewer and ask our customers to ‘bin it – don’t block it’.”

The water company wants to put up bills by a one-off cost of about £29 per household during 2014-15.