Thames Water has initiated the procurement process for the tunnelling works essential to its Teddington Direct River Abstraction (TDRA) project.

This crucial project aims to enhance London's drought resilience by providing up to 75 million litres of water daily during dry periods, supported by an innovative water recycling system.

The TDRA project is a key component of Thames Water's Water Resource Management Plan, which received government approval last year (August 2024). Funding for the project's progression has also been approved by Ofwat under Thames Water's 2025-2030 business plan. Subject to planning approval, construction is anticipated to commence in 2029.

Thames Water has issued a tender notice seeking specialist contractors to deliver two significant tunnels:

• An approximately 4.2km tunnel, constructed using tunnel boring, to connect a new Tertiary Treatment Plant (for water recycling) with the River Thames, upstream of Teddington Weir.


• A smaller diameter (up to 2.2m ID) pipe, installed using pipe jacking, to convey abstracted river flow from a new abstraction point (approximately 175m upstream of the proposed outfall) to the existing Thames Lee Tunnel (TLT).

Mohit Farmah, Head of Procurement and Supply Chain at Thames Water, emphasized the national significance of the project: "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." He highlighted the project's importance in addressing future challenges like population growth and climate change, including hotter, drier summers.

The TDRA project will enable Thames Water to abstract more water from the River Thames during droughts. This water will be transferred via a new pipeline to the existing TLT, eventually reaching the Lee Valley reservoirs to become drinking water. To offset the abstracted water and protect the environment, highly treated recycled water from Mogden sewage treatment works will undergo an additional 'tertiary treatment' stage before being released into the River Thames upstream of Teddington Weir.

Interested suppliers can access tender documents here.

To find out more about the project, visit Thames Water's dedicated website.