A pub landlord received a water bill almost £8,000 more than expected because of an undetected leak.

Dave Edwards, owner of The Rose And Crown in Montague Street, Worthing, pays £183 a month by direct debit.

He was stunned to receive an end-of-year bill from Southern Water saying he owed £7,817.

An investigation revealed a leaking pipe under the floorboards - and the utility firm told him it was his problem because the leak was on his property.

Thousands of households across Sussex who have metered water supplies could face the same problem.

Water utilities watchdog Ofwat confirmed today that any of the 26 per cent of households in Sussex with a metered water supply would be liable for leaks under their property.

After negotiations, Southern Water deducted the wastewater element of Mr Edwards' bill, reducing it to £2,379.

But Mr Edwards had to pay £1,000 for a plumber to trace and repair the leak, which involved digging up the pub floor and removing tiles.

He said: "I must run the only pub where the water costs more than the beer.

"Southern Water said it only has to read the meter every two years so if there is a problem the customer is unaware of their bill building up.

"All this came as a total shock as I pay by direct debit and expected a nil outstanding bill as usual.

"I employed a plumber who, after removing the tiles from the gents' toilet, pulling up a carpet and cutting through the floor, found a fractured pipe which he repaired.

"As a long-standing model customer who has never missed a payment or asked for any service or assistance I am disappointed Southern Water has applied the letter of the law over the spirit of service and customer care. There was no knowledge of a leak or negligence on my part and to pass on the cost to me is not just."

He warned householders thinking of switching to a metered supply to consider the pitfalls if they developed a leak on their properties.

In a letter to Mr Edwards, Southern Water said: "I must explain that the customer is responsible for all water recorded by the meter and is charged accordingly, irrespective of leakage, waste or misuse.

"A reminder of this is detailed on the reverse of our invoices. However, it is not our intention to charge for services that are not provided. In the circumstances a full allowance against excess wastewater charges has been applied to the account."

Southern Water spokeswoman Jessica Spratt said: "The company does sympathise with Mr Edwards, which is why we decided, as a goodwill gesture in light of the difficulty he would have had in locating the leak himself, to waive the £4,145 wastewater charge from his bill. Unfortunately, this does not change the fact that the responsibility for the maintenance of the leaking pipe on his property remains his own.

"The company tries to remind all customers to be aware of the possibility of leaks within their properties by including advice on their bills."

Southern Water supplies drinking water and treats waste for more than 870,000 people in Sussex.

An Ofwat spokesman said Southern Water's deduction from Mr Edwards' bill seemed fair and was something the watchdog urged other water companies to adopt.

She said: "There are isolated cases where there are seeping leaks people know nothing about.

"If you have old pipework you need to make sure it's maintained and in good order but this isn't easy to do, especially in older properties where the pipes might be underground."