File photo dated 13/3/2011 of actor Patrick Stewart

X-Men star Sir Patrick Stewart has backed a community campaign against proposals for a multibillion pound ‘super sewer’ through Bermondsey.

The former Start Trek captain and British Shakespeare Company stalwart last week joined the Save Your Riverside Action Group, in opposition to Thames Water proposals to build a £3.6 billion tunnel through Chambers Wharf.

The site is being considered for a 20 mile Thames Tunnel – dubbed a ‘super sewer’ - which would run from west to east London collecting sewage discharge triggered by rainfall.

Thames Water had been considering King’s Stairs Gardens in Rotherhithe as a preferred shaft site but local residents, along with Southwark councillors, opposed the plan as it was a green site.

The water company says the tunnel is needed to capture the 39 million tonnes of untreated sewage which is discharged into the Thames every year.

But residents fear the works will take over parks and protected spaces for years, reduce house prices and leave ugly concrete shafts and service buildings.

Sir Patrick Stewart said: “Of course Thames Water are addressing environmental, health and living concerns for all Londoners. What they seem to have overlooked in focusing their attention on Chambers Wharf is that those very same concerns, environment, health and living conditions may be unimaginably damaged, restrained and blighted for a significant number of years. There will be a period of time where Thames Water is planning to work 24/7 for three years - you don’t need to have an actor’s imagination to know what this would mean to us as individuals and to the neighbourhood as a whole.”

Thames Water’s head of London Tideway Tunnels, Phil Stride, told the BBC: “When Chambers Wharf came up for sale we had to act quickly to ensure we could consider the land in detail as a potential site. It is vital that we keep our options open.

“I must stress that this does not mean we will definitely use it or that we have discounted King’s Stairs Gardens.

“There is still a lot more work to be done, including further discussions with local communities, before we make any final decisions about the construction sites we need.”

Thames Water hopes to submit a planning application in 2012, with construction due to be completed in 2020.