The chief executive of Southern Water is stepping down from his £300,000-a-year job.

Les Dawson will leave the utility company after five years in charge this summer.

It is not known if Southern Water, which saw its operating profit for 2008-09 increased by 32.4% on the year before to just over £314 million, is paying the 53-year-old a “golden goodbye”.

A spokesman for the company would not comment on the issue.

Although Mr Dawson is not leaving until the summer, current financial director Howard Goodbourn has been appointed as interim chief executive with immediate effect.

The Southern Water spokesman would not say why both men needed to be in charge other than the arrangement was “to ensure that there is a smooth transition and that it is business as usual”.

Announcing his decision, Mr Dawson, who also took home £210,000 in bonuses in 2008-09, said it was “the right time to leave” the company.

He said: “Having just successfully delivered the company’s largest ever capital investment programme of nearly £2 billion between 2005 and 2010 and also completed the five-yearly price review with our industry regulator Ofwat, I feel it is now the right time to leave.”

“I firmly believe we have transformed the performance of Southern Water. The record speaks for itself.

“We have improved all aspects of our business and now lead the industry in many areas while we have also become recognised as a major supporter of the communities we serve in the South.”

Mike Welton, chairman of Southern Water, said that he and the board regretted Mr Dawson's decision but understood its timing.

He thanked Mr Dawson, who was awarded the OBE in 2009, for all his efforts and achievements on behalf of the company and wished him good fortune in the future.

Mr Dawson has overseen Southern Water's plan to install water meters in every household in the next five years.

He was also behind the controversial introduction of season tariffs to prevent droughts, which will see people charged more for water in the summer than in the winter.