London’s sewage system was built in the Victorian era and while, it still works well, increased pressure means untreated human waste flowing into the Thames on a weekly basis.

There are 57 overflow points along the river, which were built as a safety feature to prevent the sewers – which capture both sewage and rainfall – from backing up into streets and gardens when full.

Used only occasionally in the 19th century during a heavy storm, these overflows can now discharge sewage into the river after as little as just 2mm of rainfall.

Yesterday (September 13) Thames Water launched a 14-week public consultation on plans for the planned super sewer, which it hopes will ‘significantly reduce’ sewage discharges into the River Thames.

The tunnel will run up to 20 miles from its starting point in west London, and will broadly follow the route of the river at a depth of up to 75 metres, to the east of Tower Bridge before going one of three ways:

·north east to connect to the Lee Tunnel at Abbey Mills in Stratford – the shortest of the proposed routes;

·east following the river and crossing the Greenwich peninsular up to Beckton Sewage Works in Newham;

·or south east, straight to Greenwich and then on to Beckton.

Public exhibitions will be held across London from 27 September until 22 October 2010. This will provide all interested parties with ample opportunity to understand and influence the development of the project, and have their say on the preferred route and construction sites.

Thames Water’s chief executive, Martin Baggs, said: “Allowing sewage to continue to overflow into the river at the current frequency is unacceptable.

“This causes significant environmental damage – killing fish, polluting the river for those who wish to use and enjoy it and affecting the wellbeing of our capital.”

London waterways charity Thames21’s chief executive, Debbie Leach, welcomed the plans, but warned of distribution.

She said: “Delivering the sewer is going to be challenging and difficult, not just for the engineers, but also for many of us living in London.

“It isn’t going to be easy, but that goes for most things worthwhile. I encourage all Londoners to view the proposed plans with an open mind and be aware of the huge benefits the tunnel will achieve for the city.”

People can take part in the consultation by visiting the Thames Tunnel consultation website:

Luke Walsh

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