Gerrard brings more than 30 years’ experience in the development and delivery of major infrastructure investments working as a financial fixer.

His most recent appointments were as CEO of Partnerships UK and of Local Partnerships – both organisations charged with delivering investment in economic and social infrastructure through public-private-partnerships.

Martin Baggs, chief executive of Thames Water, said:  “I am delighted that Michael Gerrard will be joining Thames Water to run this major infrastructure project, which is so important for London and has reached a crucial phase in its development.

“Michael brings a strong background in infrastructure delivery and of partnership working between industry, the City, the public sector and users of public services.”

The Thames Tunnel is being designed to capture flows from the 34 most polluting combined sewer overflows that discharge untreated sewage to the River Thames.

These discharges, which can be triggered by as little as 2mm of rainfall, occur when the capital’s Victorian sewer network becomes overloaded.

For the last few years Gerrard has also been a member of Defra’s Waste Infrastructure Delivery Programme Executive and the Welsh Assembly Government’s waste investment programme board.

Gerrard said:  “This is a crucial investment for London and an exciting opportunity to help bring its infrastructure up to modern-day standards”.

“I look forward to leading the excellent team that has been mobilised and to taking forward the next phases of the impressive works that are already under way.  “I will be working closely with the many stakeholders that are vital to the success of this important project.”

The project will enter its second more detailed consultation phase in September after four months of public consultation in London.

A planning application for the project will be submitted next year to meet the schedule date to break ground in 2013.