Light at the end of the tunnel for 4.2bn 'super sewer'

Construction of London’s new ‘super sewer’ will start next year following the successful completion of a £4.2bn contract.

Government Legal Department (GLD) lawyers have guided the successful completion of the contract, which will see the construction of one of the biggest tunnels in the world.

Reaching this milestone brings the government a significant step closer to modernising London’s stretched Victorian sewerage system. 

Thames Tideway Tunnel will stop the millions of tonnes of sewage that currently overflow into the river each year, protecting it’s ecosystem and health of those who use the river.

Over the past five years a group of legal advisers have negotiated a way through many of the obstacles that threatened the project. They have developed a unique legislative and regulatory framework that underpins the model that has been used for delivering this infrastructure project. This has reduced the expected cost to Thames Water’s customers significantly.

Granted development consent last year, the project will be financed and built by the private sector and will become one of the first greenfield infrastructure projects that pension funds have invested in. 

Private investment would not have been possible without the package of contingent government financial support. This government package is designed to remove project risks that private sector investors would not have been prepared to take. 

The Thames Tideway Tunnel has not been without controversy. Lawyers have steered development consent for the tunnel through four judicial review challenges brought by organisations opposed to the project. The successful defence of these challenges was critical to the delivery of the tunnel.

As the construction gets underway, Defra legal advisers will continue to advise on reducing the risk of fines being imposed on the UK for failing to comply with the Urban Waste Water Treatment Directive.

GLD legal director at Defra, Alan Evans, said: “The Thames Tideway Tunnel is many times larger than any previous project in the water sector, with a price tag of more than £4bn and the added complication of digging under the entire length of a major capital city.

“There is a huge sense of professional pride in knowing that we have been critical in ensuring the go-ahead of this world-leading infrastructure project. A project that will boost economic growth, generate more than 9,000 jobs and bring huge benefits to the natural environment.

“It has been a huge team effort over five years, drawing on the expertise of many lawyers across GLD, from developing legislation to judicial review litigation and from contract negotiation to planning applications and securing state aid approval. It is a great demonstration of what we can achieve.”

Last month Ofwat awarded a licence Bazalgette Tunnel Limited to finance and deliver the Thames Tideway Tunnel following a tendering exercise carried out by Thames Water.

At the same time, Thames Water announced a much lower than predicted cost of the project to customers. The company’s current average household bill for water and wastewater of around £370 per year is now expected to remain at that level, before inflation, until at least 2020. 

Construction of the tunnel will start next year and is expected to take seven years to complete. It will follow the Thames 25km from Acton in West London to Stratford at depths of up to 65 metres below the river.

Andy Mitchell, CEO at ‘Tideway’, the delivery organisation for the Thames Tideway Tunnel, now owned by Bazalgette Tunnel Limited, said: “Our task over the next seven years is quite simply to make sure London has a sewerage system capable of meeting the capital’s modern-day needs. 

“It’s not just about cleaning up the river, important though that is. Nor is it just about building a tunnel. It’s about making sure we transform the River Thames, making it central to the capital’s wider social and economic well-being. 

“This is a once in a generation opportunity and we are determined to raise the bar in every way, not least the way we treat local communities potentially most directly affected by construction works.”