Britain’s most expensive water firm could have to repay thousands of customers after a landmark action, a watchdog said today.
Officials at Ofwat say South West Water has been overcharging some of its 1.5 million customers for sewage disposal.
The company has been charging homeowners for disposal of surface water despite them having ‘soakaway’ systems installed.
New homes built with a soakaway system should not be paying the same as those where surface water runs off into sewers.
Up to 90 per cent of new properties built over the past ten years had soakaway drains but South West Water automatically charges households a tariff for disposal of surface water.
One landlord from Exeter, Devon, has successfully won a rebate of £7,000 after he was overcharged on all of his properties since 2004.
A spokesman for Ofwat said properties with soakaways should not incur a sewerage tariff for surface water into drains.
He said: ”Since April 2000, we have required all sewerage companies to offer customers a rebate for any surface water drainage charges paid within the current charging year, if they can prove they do not receive a surface water drainage service.
”We think companies should provide rebates automatically in cases where they are aware that a property is not connected for surface water drainage.”
The firm’s 1.5 million customers in Devon and Cornwall already pay the most expensive water bills in the country.
An average bill in the area is £414 compared with £254 paid by Thames Water customers in London.
A spokesman for South West Water said: ”Customers who do not discharge surface water from their homes to our sewers do not have to pay for this service.
”Customers who think their property does not have a surface water drainage connection can call us.”