The new super sewer system is just a couple of bolts away from being ready to carry millions of tonnes of Londoners’ waste.
Thankfully, the London sewers and whatever is inside them are usually out of sight and out of mind.
But for the past ten years, construction has been going on to get the 16-mile super sewer ready to carry human waste and rainwater in the new Thames Tideway Tunnel.
Most of us rarely think about the network of pipes and sewers that keep the city from smelling like a Victorian wasteland, but around £5,000,000,000 has been pumped into the megaproject designed to prevent raw sewage from ending up in the River Thames.

Now the super sewer is fully connected to all the pipes, so here is a look inside it.
How the Thames Tideway Tunnel super sewer works
The super sewer has been built to future-proof the ageing London underground waste network – parts of which were built in the mid-19th century.
London’s population has also grown since the Victorian times, meaning the city’s demand has burdened the sewage system.
It will divert 34 of London’s most-polluting sewage outflows, preventing them from flowing into the river and ending up in nature.
At 24-feet wide, the super sewer has capacity for 600 Olympic swimming pools of liquid.

The tunnel diameter could fit three buses side-by-side.
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It starts from Acton, west London, and cuts through the heart of the capital deep underground until reaching the Lee Tunnel in east London.
From there, Lee Tunnel will carry effluent to the Beckton Sewage Treatment Works.
Along the way, sewage flows through pumping stations and underneath overground tunnel shafts.
Tideway, the company behind the project before it is handed to Thames Water, said the sewers have already prevented 2,200 Olympic-sized pools worth of waste from ending up in the Thames.
Andy Mitchell, the Tideway chief executive, said: ‘This is another significant step forward – with this final connection complete, the super sewer is fully up and running and protecting the Thames.’
After some final tests, the super sewer will be handed to the ownership of Thames Water who will be responsible for it.
Thames Water customers have footed the bill for the super sewer construction.
Thames Water, which has been marred by sewage discharge and major debt issues, has insisted that it is fair for the company to take over the project despite its ‘challenges.’
Sadiq Khan, the Mayor of London, said the super sewer will ‘mean a huge reduction in sewage going into the tidal Thames,’ adding that the city has to ‘now build on this work to go further and tackle the other sources of pollution damaging London’s waterways.’
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