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Tunnel Beneath the Thames

30 minutes
First broadcast:
Tuesday 21 February 2012

Every time more than two millimetres of rain drops onto the streets of London a combination of raw sewerage and rainwater overwhelms the Victorian sewers and pours into the River Thames, killing fish and disgusting the users of the river.

The solution being proposed by Thames Water is an enormous 15 mile long tunnel buried beneath the river as it flows through the city. There's little doubt that it will clean up the river but is the health of a few fish really worth over £4 billion of Londoners' money and years of disruption for those who live close to the tunnel construction sites?

In 'Costing the Earth' Professor Alice Roberts descends into Joseph Bazalgette's Victorian sewer system to see the extent of the problem and the scale of the new works.

Producer: Martin Poyntz-Roberts.

  • Costing The Earth about to descend into London's sewers

    Costing The Earth about to descend into London's sewers

    Professor Alice Roberts and Richard Aylard from Thames Water head into London's underground network of sewers to witness how raw sewage is pumped into the River Thames when as little as 2mm of rain falls on the capital.

  • And deep in the dark depths

     And deep in the dark depths

    Professor Alice Roberts and Producer Martin Poyntz-Roberts admire the sticky brown slime.


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  1. Image for Costing the Earth

    Costing the Earth

    Man's effect on the environment, questioning accepted truths, challenging those in charge and…

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