Thanks to the work of London plumber Thomas Crapper, the popularity of the flushing toilet grew rapidly in the first half of the 19th century.

By the mid 1900s there were an estimated 250,000 new WCs putting an enormous strain on the capital’s medieval sanitation system.

Cholera was rampant and the problem was getting up the noses of the country's ruling elite. By 1858 politicians were debating whether to vacate the newly opened Palace of Westminster to escape the "great stink".

The solution, masterminded by engineer Sir Joseph Bazalgette, was Crossness Pumping Station, built on a remote part of the old Erith marshes.

This triumph of Victorian engineering opened in 1865 and used the four largest rotary beam engines in the world to pump London's sewage out on the ebb tide of the Thames.

Sir Joseph’s great-great grandson, is the president of the Crossness Engines Trust, Peter Bazalgette.

Mr Bazalgette retired from his role as creative director at Endemol, the makers of TV programme Big Brother, at the end of last year.

He joked about his ancestral legacy: “The hereditary principal is not in fashion, but it appears I inherited a shit works.

“When I walked in 20 years ago it took my breath away.

“It is a functional piece designed to pump human excrement, but it is built like a cathedral because it is Victorian.

“When I saw the size and grandeur of it I understood immediately, along with the volunteers, that we had to find a way to preserve it."

He added: “I feel enormously proud. It is an amazing thing for my ancestor to have created.”

Thanks to a team of dedicated volunteers and Mr Bazalgette’s profile raising efforts, one of the beam engines has been fully restored.

And the Heritage Lottery Fund has pledged £1.5m to restore the buildings which house them.

The Grade 1 listed Beam Engine House and Boiler Room are currently both on the English Heritage register of buildings at risk.

But a project, due to start early next year will see the buildings conserved and a exhibition about the social history of the site installed.

Further works will include a cafe, a car park, an access road, an education room and an archive, bringing the total cost for the project to nearly £4m.

The significance of the site justifies the cost says Mr Bazalgette: “It is a Grade 1 listed industrial building.

“And in south east London the only other one is Tower Bridge, one of the most famous buildings in London.

“This one is of similar significance because it houses the four largest steam beam engines in the world, so it is an important piece of industrial heritage.

“It symbolises one of the most fascinating periods of London’s history, when it was at the centre of the British Empire.

He added: “London was growing very fast but it couldn’t grow without a sewage system.

“This station was the heart of that system, so it is at the heart of the story of London and its history.

Mr Bazalgette was formerly the chairman of the Crossness Engines Trust but has handed over the role to Jonathan Rooks.

He said: “I was chairman for about a decade but once we raised the funding, announced here today, I thought it was time to hand over to a local chairman.

“At the end of the day this will be a community asset for Bexley, so Jonathan Rooks has become the chairman.

“He is the right person to take the project forward as it is a project for south east London.”