Thousands of people across Sussex have received reductions in their water bills after we revealed they were paying for a service they had not received.

Southern Water has reduced bills for 18,000 people who paid for rainwater drainage.

A high proportion of customers did not use the service as the water simply drained away into soakaway systems and did not reach the public sewer.

Southern Water has agreed to the reductions, but will not be backdating them to cover payments in previous years.

The Argus revealed in May that Southern Water was billing all 593,000 Sussex customers for the service, whether or not it was needed.

It was ordered by industry regulator Ofwat to pay back the £18 it had wrongly charged in the last year.

But customers had been paying the annual fee since privatisation of the water company in 1989.

Our money Down the Drain campaign highlighted the situation and led to the Worthing-based firm making the rebates totalling £324,000.

More than 470 people wrote direct to the Argus demanding their money back and the letters were handed to Southern Water's managing director by MP David Lepper.

Now Southern Water has revealed that it has so far received 25,910 requests for forms outlining how to get a refund.

Of the forms sent out, 18,140 have been returned and about 18,000 have been processed and led to £18 rebates and reduced water bills in future.

Tony Prince, a Telscombe councillor, said he was not surprised by the huge number of people who demanded their money back.

He said: "I don't think people would have noticed this charge if it hadn't been for the publicity.

"If you multiply the £18 they gave to everyone by ten years it is millions, which is shocking."

Michael Anthony, of Tredcroft Road, Hove, was one of the thousands of Argus readers who demanded a rebate.

Now he has been promised that £18 will be taken off his next bill.

He said: "It's very exciting that so many people have got their money back and it's thanks to the Argus because they took it on and showed they were on our side."

Mr Lepper, Brighton Pavilion MP, said: "The Argus has done everyone a good service by highlighting this issue. It has obviously been especially good for the thousands of people who have benefited financially by getting the rebate.

"The Argus has highlighted that unfortunately we have a water company that until it's compelled to act is very reluctant to meet all its responsibilities to its customers."

Mr Lepper wrote to Ofwat asking if his constituents were entitled to refunds going back to privatisation in 1989 and if the firm could be forced to take a more 'pro-active' role.

A Southern Water spokesman said: "The Argus campaign supported our publicity for the rebates."