A water firm which has banned 875,000 Sussex residents from using hosepipes wasted 93 million litres of water a day last year.

New figures show Southern Water increased the amount of water it loses to leakage in 2005/06.

It was one of only four firms in England and Wales to fail to meet its target for leak reduction, losing the equivalent of 37 Olympic-sized swimming pools every day.

Meanwhile, bills have gone up across the region by 5.9 per cent compared to a national average of 5.5 per cent, putting a standard bill up from £296 to £313.

Des Turner, MP for Brighton Kemptown, said: "People are paying through the nose for water and sewage when they can't actually use much water.

"All privatised water companies are is a vehicle for printing money."

Dr Turner said the firm needed to concentrate on leak reduction and ways of providing more resources in the future.

He said: "A lot of MPs are complaining bitterly about their plans to build a sewage plant on the South Downs.

"There is no doubt there is a need for more investigation into reservoirs. I believe Southern Water actually closed down some of the bore holes which, had they been available now, might have helped."

Gill Mitchell, Brighton and Hove City Councillor for the environment, said: "It isn't right that leaks are not being brought under control at a time when households are being urged to reduce their water consumption during the drought.

"This is unwelcome news."

She understood Southern Water was about to start a multi-million pound pipe replacement programme in the city, which might improve its performance.

Southern Water supplies tap water to 397,472 properties with 875,000 inhabitants across Sussex. Other homes are served by South East Water and, in the Gatwick area, by Sutton and East Surrey Water.

South East Water met its target for the fifth year, this time leaking 69 million litres a day. The firm loses 17 per cent but said a third of this relates to supply pipes which are the customer's responsibility.

Sutton and East Surrey Water leaked 24 million litres - less than its 25 million target.

One Southern Water customer, Duncan Brooker, of Downsway, Shoreham, has been waiting a month for a leak to be fixed. The leak is in his neighbour's pipe but Southern Water promised a free repair.

Mr Brooker, 47, a software engineer, said: "I worked out it is losing 1,000 gallons a day. It is disgraceful. My children are learning about the drought at school. We are doing everything we can in our house to save water - not flushing the toilet and sharing baths. In our garden it is all going down the drain."

A Southern Water spokeswoman said an engineer fixed one leak in the pipe at the beginning of July but there must be another one. She promised the second leak would be fixed for free within days.

She said the firm had the lowest leakage level, at 15 per cent, of any of the ten water and sewerage companies in England and Wales. The target had been missed because a cold wet spell caused soil movements and put strain on the pipes.

Andy Watson, Southern Water's director of operations, said: "Last year we narrowly exceeded our regulator's annual target but continued to meet our three-year rolling target.

The other firms to miss their targets were Severn Trent, Thames and United Utilities.

Southern Water has permission to introduce a drought order restricting commercial water use this year for the first time in its history.

Martin Baggs, South East Water's managing director, said: "Our excellent year-on-year performance has helped reduce leakage over the last ten years from 97 million litres to 69 million litres a day.

"We would also like to thank our customers for their support."

Customers can report leaks in the water mains by calling 0800 820999.