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London Tideway Tunnel Super Sewer Now Online!
At the start of the year, analysis from New City Hall was published revealing that sewage incidents polluting London’s rivers in 2023 were nearly five times the amount for the same period in 2022, with Thames water releasing sewage into the capital’s waterways for 6,590 hours, 11 minutes and 54 seconds between April and December 2023.
Over the course of just six days in December, sewage was dumped across the network for 128 hours and 12 minutes, including treated and untreated sewage into rivers during periods of intense rainfall.
At the time, mayor of London Sadiq Khan said: “London’s rivers are the arteries of our city. Frankly, the current state of some of our rivers is appalling and only getting worse. Thames Water urgently need to up their game and get a grip of the situation. At the same time, ministers are standing by and letting more and more dirty sewage flow into our rivers.
“We need tougher legislation that forces water companies to act as a matter of urgency. While we’re making huge progress cleaning up London’s air and much of the capital’s environment, it’s a scandal that levels of sewage in our rivers are increasing at the same time.”
To help address the issue and tackle London’s sewage pollution problem head on, an eight-year construction project has been underway to help protect the city’s rivers… and it has just been switched on!
Momentous occasion!
In May, the 25km London Tideway Tunnel was connected to the 6.9km Lee Tunnel to complete the full network, which boasts a combined capacity of 1.6m m3 to protect the River Thames – and today (October 14th), the new super sewer went live for the very first time.
A series of gate-like valves are now open at four of the 21 locations that comprise the network, with the rest expected to be turned on over the coming months to bring the sewer to full operating capacity – the equivalent to 640 Olympic-sized swimming pools.
To get the system up and running completely, the remaining discharge points will need to be connected to the new super sewer and the network tested during different weather conditions. The testing phase has now begun, with work continuing above ground to finish the riverside public spaces that have been included as part of the project.
It’s expected that once the super sewer is fully operational, it will practically eliminate the harmful effects of sewage pollution on the river through Central London.
Andy Mitchell, Tideway chief executive, said: “This is an important moment for the Thames. The super sewer has been switched on and is starting to protect the river from sewage pollution. After eight years of construction, in which almost 25,000 people have contributed more than 40 million working hours, this system is operating for the first time.
“These are early days, with more connections to make and further testing to come, but the super sewer’s positive influence on the health of the Thames will increase over the coming months – and London will soon be home to the cleaner, healthier river it deserves.”
Getting to know the Tideway Tunnel!
The Lee Tunnel was the first of two projects to go live as part of the Thames Water London Tideway scheme, running 6.4km through East London from the Abbey Mills pumping station in Stratford to the Beckton sewage treatment works in Newham.
This tunnel has been in operation since 2016, with the full network now up and running with the connection of the new super sewer.
This new sewer is 7.2m wide in diameter – the same as three of London’s doubledecker buses! Its two connection tunnels are five and two metres in diameter respectively.
The tunnel begins at Acton in West London, where it is at its shallowest – a depth of 31 metres. From there, the tunnel falls away at a rate of one metre per 790 metres, hitting a depth of 66m at Abbey Mills.
In all, 21 shafts were constructed across the network, some of which were to launch tunnelling machines to help excavate the main super sewer, although the majority are used to direct sewage flows.
The first data review is now in for the project, revealing that in just one single day – September 23rd, when heavy rainfall was seen across the city – 589,000 m3 of sewage was captured by the Tideway Tunnel, and that’s with just the first four connections activated… which is excellent news for the future, once all 21 are switched on.
Business sustainability
If you’re a business in London or elsewhere in the UK, you too can do your part to help protect the nation’s waterways and safeguard resources for future generations.
If you’d like to find out about water sustainability and how you can improve your water footprint, perhaps quite significantly, get in touch with the H2o Building Services team today.