WATER bills could be £440 a year for Oxfordshire residents at the very least within the next seven years.

Thames Water announced plans to hike bills by an average of £100 to pay for infrastructure improvements.

Britain’s largest water company, which has the worst leakage record in the UK, plans above inflation increases for five years from 2015.

Figures obtained by the Oxford Mail show customers paid on average £201 a year for water in 2003. But a decade on that number has shot up 76 per cent to £354.

It means the average water bill for an Oxfordshire resident has risen £153 in 10 years.

Now the company wants to review current price rules agreed with regulator Ofwat and to increase customers’ bills by at least £16 next year.

If Ofwat agrees bills will rise one per cent above inflation for five years from 2015. Once inflation is added, the bill will rise even higher. Another £70 to £80 will be added to pay for the Thames Tideway Tunnel.

Andy Webster, who lives in Earl Street, Oxford, was one of many residents affected by flood problems before Christmas. He said: “We are just cash cows to Thames Water. There is nothing we can do. They give the same excuse every time, but they do nothing for the sewers here in Oxford. We see these problems every time it rains and still we have to pay.”

Thames Water is owned by a group of investors and run by an Australian bank.

Martin Baggs, the chief executive, raked in a £420,000 bonus on top of his £425,000 salary last year and is in line for a £1m payout on the company’s performance through to 2015.

In 2003 the company recorded a £63m profit and was criticised for its poor record on pollution and leaks.

In 2004 the company said households would see average bills rise from £201 to £280 over a six-year plan to finance a £4bn investment programme. As part of this it implemented a 21 per cent rise.

Thames Water said it will invest £4.9bn in improving its service by 2015.

Thames Water spokesman Natalie Slater said: “Our customers’ bills are the second-lowest in the country, at less than £1 a day per household, while we continue to invest a record £1bn a year in infrastructure upgrades – more than any other company has.”

Thames Water reported a pre-tax profit of £112.6m for the six months to October 2012. Latest leakage stats showed it lost 608 million litres a day.

The Thames Tideway is a proposed 25km tunnel underneath the Thames through London to store and transport raw sewage and rainwater which currently overflows into the river.

GOING UP

Thames Water average Oxfordshire bills:

Year  Average Bill  Rise

02/03 £ 201 
04/05  £208  3.5%
05/06  £252  21.2%
06/07  £265  5.2%
07/08  £278  4.9%
08/09  £291  4.7%
09/10  £302  3.8%
10/11  £307  1.7%
11/12  £318  3.6%
12/13  £336  5.6%
13/14 £354  5.5%