Last Thursday, 12 September, the UK Planning Inspectorate – the government body responsible for national infrastructure planning – began looking into the feasibility of London’s proposed new ‘super sewer’, the Thames Tideway Tunnel.
The owner and operator of London’s existing sewers, Thames Water, has claimed that, although sound, the Victorian system is now simply too small to transfer the Capital’s waste to its treatment works for processing. It reports that, as a result, around 39 million tonnes of untreated sewage flushes into the Thames in a typical year.
The scheme has its share of vociferous opponents, with concerns that the scale of the disruption involved in creating what would arguably be Europe’s largest sewer system would devastate local commerce and ruin residents’ quality of life. Suggestions include the creation of ‘living walls’ and roofs that send rainwater straight back into the ground rather than down into the sewerage system.
However, Thames Water is adamant that having looked into all the possible solutions over the past 13 years, the Thames Tideway Tunnel is the only viable way forward.
Should it be given the go-ahead, Thames Water’s website states that the tunnel would be “between 6.5 and 7.2 metres in diameter, 66 metres underground at its deepest point and 25.1 kilometres (15.6 miles) long – making it one of the largest and deepest tunnels under London”.
It explains that, in general, the tunnel needs to follow the route of the River Thames so that it can be connected to the combined sewer overflows (CSOs) that are located along the riverbanks, adding, “Following the route of the river also means that we can make use of the River Thames itself to transport materials and minimise the number of existing buildings and structures that the tunnel will pass beneath.”