The Thames Tideway Scheme: What is it?

The population of London is around 8.9 million (2019), which is more than double the population in 1875, when the first sewage system was built. Given the lay of the land and the population, the system is designed to carry overflow waste straight into the Thames, which causes significant harm to the environment. To evolve with the times, the Thames Tideway Scheme was launched, which will see a state-of-the-art sewage tunnel run underground from Acton to the Abbey Mills Pumping Station (Stratford). 

River Thames London

A Short Background of the London Sewage System

The original London sewage system finished construction in 1875, and it was designed to capture sewage and rainwater runoff. This isn’t too different to how sewage systems work today, but it was planned around a population of over 4 million residents – the current count sits at more than double. 

Way back then, the area had a lot more green spaces, which meant a lot of rainwater was soaked up into the ground before it reached the Thames. However, hard-surfaced spaces have been growing by more than double the area of Hyde Park since 2001. 

Given how much expansion has taken place, the original sewage system simply can’t cope. All it takes is a short 2mm of rainfall to trigger an overflow, which happens around 50 times a year. 

Read our article on the History of the London Sewer System

What is the Thames Tideway Scheme?

The Thames Tideway Scheme is a 16-mile combined sewage tunnel being constructed under the Thames estuary. The tunnel will clean up the river Thames by collecting all of the raw sewage released into it every year. 

When a large amount of rainfall exceeds the capacity of existing sewage tunnels, which happens a lot in the UK, it causes the overflow system to kick into action. The sewage in the Thames pollutes the environment by damaging wildlife. Additionally, given that the Thames is often used by people for water sports like kayaking, the sewage can lead to certain health conditions.  

Who is Building the Thames Tideway Tunnel?

The mammoth project is being led by Tideway (Bazalgette Tunnel Limited). They are responsible for building, financing, maintaining, and operating the Tideway Tunnel. The project is being funded by a series of investors including DIF, Dalmore Capital, Amber Infrastructure, and Allianz. 

A project like this is a huge undertaking, which is why the total projected cost was initially £3.8 billion, but that estimate has been updated to £4.5 billion. On top of this, Thames Water put up £1.1 billion to complete preparatory works. Given this project is of direct benefit to the residents of London, Thames Water’s 15 million customers are paying the price through their monthly bills. 

When Will the Thames Tideway Scheme Be Completed?

Community consultation for the Tideway Tunnel started back in 2011, but it wasn’t until September 2014 that the Secretaries of State granted planning permission. By 2016, the Thames Tideway Tunnel’s construction had begun, but it took a further two years until the tunnel itself started to be built. The tunnelling phases ended in 2022. 

In 2022, the tunnel should have been only two years away from completion. However, when Covid-19 took hold of the world, restrictions delayed the project by an extra year. At this point, testing and commissioning will take place over the next couple of years and the project will be fully completed by 2025.

The Loo Gardens and Thames21

As part of the project’s attempt to give back to the community, Tideway and the Joy Collective designed the Loo Gardens, which is a unique rainforest art installation 50m underground. As a visitor, a crane will lower you down in a metal cage, where everything feels dark and drab. However, once you set eyes on the stunning installation, it truly provokes thoughts about what the Thames Tideway Scheme symbolises. 

The Thames21 charity is committed to cleaning up miles of neglected sewage systems while reigniting community relationships with the Thames. This is something we support 100%, as our teams are experts in sewage cleaning and drain clearance. 

How Many Jobs Did the Thames Tideway Scheme Create?

We’ve already discussed the clear benefits of the tunnel in terms of the environment, but it has also helped the economy. For example, when the project first launched, it created over 9,000 jobs spread across both direct and indirect roles. 

The Thames Tideway Scheme is nearing the end of its timeline, but the benefits it will hold for the London community and the environment will last for up to 100 years. 

If you have a drainage emergency in London then First Response Drainage can help. Call our team on 0800 043 4860 and, if possible, we will respond within an hour.