Pensioners living alone in one-bedroom flats in Oxfordshire are being charged more for water than families in three-bedroom homes, the Oxford Mail can reveal.

The news emerged as Thames Water planned to roll out its new charging system for households unable to have water meters.

The company has promised to look into the matter - brought to its attention by elderly residents in Bicester, many of whom are paying twice as much as immediate neighbours because they have yet to apply for a meter or are unable to have one installed.

Estate manager June Hepworth, who runs Hanover Gardens in Bicester, said 27 out of 69 flats in her sheltered accommodation block were affected.

She said non-metered residents had been charged £260 for the next 12 months - £140 more than those with meters.

She added that she and her husband's annual metered water bill was £210, and they lived in a three-bedroom detached house.

"A lot of them are very frustrated and very unhappy," she said.

"They feel they are being exploited. It just seems ridiculous they are paying so much for the amount of water they use - it's scandalous."

Mrs Hepworth said residents were passed from pillar to post when they called Thames Water to sort out the problem.

Banbury MP Tony Baldry, who called the situation "wholly unjust", has also written to Thames Water's managing director about the issue and threatened to raise the matter in the House of Commons if the bills are not reduced.

From April, Thames Water is introducing a new banding structure for households whose bills are based on the average metered bill because they are unable to have water meters installed.

It does not affect customers charged according to the rateable value of their property or those with meters.

The Assessed Household Charge puts properties in one of three bands. One-bedroom homes should see bills fall to £200 and two-bedroom ones to £217 - both down from £245.

People living in homes with three or more bedrooms - regardless of how many people are resident - will see bills increase from £245 to £266.

Thames Water spokesman Don Sharples said one possible reason why pensioners at Hanover Gardens had been charged so much was because they had failed to complete a survey sent to customers last June.

He explained those people who failed to return the form would be charged the maximum amount under the new charging system for people who could not have meters installed.

But he said £260 was too much for residents living in single bedroom flats to pay and promised a Thames Water team would visit Hanover Gardens to talk to residents directly about reducing the bills.

He said: "We are trying to make the system as fair as possible and I'd encourage residents to give us a call if they feel there is some injustice. It's not in out interest to have any of our customers charged unfairly."

Johanna Whyte, 83, is one of 27 residents at Hanover Gardens facing a bill of £260 for her annual water supply.

She said she paid more for water than her son, who lived with his partner in a four-bedroom house, with a shower, bath, two toilets, a dishwasher and washing machine.

Mrs Whyte, who has lived in Hanover Gardens for eight years, said: "I have phoned many times and that's what Thames Water say I must pay.

"I don't use very much water. I take a bath a couple of times a week because I find it difficult to get in and out, and I save my dishes up and wash them at night.

"I used to pay £8 a month when I lived in a metered flat. It's very unfair. Why should I pay so much when people with bigger places pay a lot less?"

Mrs Whyte said she could not remember receiving a letter from Thames Water about the new banding system.

However she had been told she could not have a water meter installed.