Thames Water has launched procurement for the £242 million tunnelling works required to deliver its Teddington Direct River Abstraction (TDRA) project.

The company says that the TDRA project would provide up to 75 million litres of water each day during drought, supported by water recycling. 

The project forms part of Thames Water's Water Resource Management Plan (WRMP), which was approved by the Government last year, and which sets out the company's plans to secure water supply for the next 50 years and beyond.

Funding to progress the project has also been approved by Ofwat under Thames Water's 2025 – 2030 business plan, with construction anticipated to start in 2029, subject to planning approval. 

Thames Water issued a tender notice on Wednesday (28 May) for the tunnelling and connection works required for its London drought resilience project. 

The company says it requires specialists who can deliver two tunnels including:  

• An approximately 4.2km route using tunnel boring to connect the new Tertiary Treatment Plant (water recycling) and the River Thames, upstream of Teddington Weir.
• River abstraction and transfer to the existing Thames Lee Tunnel (TLT): The river abstraction would be located approximately 175m upstream of the proposed new outfall. The abstracted river flow would be conveyed to the TLT through a smaller diameter (up to 2.2m ID) pipe installed using a pipe jacking technique.

Head of Procurement and Supply Chain at Thames Water, Mohit Farmah said: "We're seeking industry leading tunnelling experts to help us deliver this nationally significant infrastructure project, as we work to secure water supply for millions of Londoners.

"The capital city and our customers rely on us for a safe and secure supply of water and this project will be vital as we work to meet the challenges ahead, from a growing population to the effects of climate change, including hotter, drier summers."

Thames Water's TDRA project would enable the company to abstract more water from the River Thames during periods of drought, upstream of Teddington Weir.

The water would be transferred along a new connecting pipeline to an existing underground tunnel. It would then join the Lee Valley reservoirs in East London, ready to become drinking water, according to Thames Water.  

The company added: "To replenish the river, highly treated recycled water, which has gone through an additional cleaning stage known as 'tertiary treatment' would then be transferred from Mogden sewage treatment works and released into the River Thames at a new discharge location upstream of Teddington Weir.

"This would compensate for water taken to help protect the environment and local wildlife."