London Super Sewer’s forward step

A specially-created new company has been chosen by Thames Water as preferred bidder to deliver the Thames Tideway Tunnel – also known as the Super Sewer – a £4.2 billion (€6.03 billion) project under London, UK.

Bazalgette Tunnel, whose shareholders are a consortium of investors comprising funds managed by Allianz, Amber Infrastructure Group, Dalmore Capital and DIF, is in line to own, finance and deliver the project.

The appointment of the infrastructure provider will be subject to formal designation and licensing by the UK water industry’s economic regulator, Ofwat.

The tunnel will be 25km long and 7.2m wide, and will be between 35m and 65m deep. It will be a new part of the London sewer network and its construction is required to tackle the discharge of untreated sewage into the tidal River Thames, and to increase the capacity in the sewerage network.

Starting in West London, the main tunnel will follow the route of the Thames to connect with the existing Lee Tunnel, with sewage being transferred to the Beckton Sewage Treatment Works in East London.

DIF, an independent fund management company, said that along with the recently completed upgrade of five sewage treatment works on the tidal Thames – including Beckton – both the Lee Tunnel and the Thames Tideway Tunnel were needed to stem the 39 million tonnes of untreated sewage that overflowed into the tidal river in a typical year from the capital’s overstretched Victorian sewerage network.

Construction of the project will be under three main joint venture contracts, with BMB JV – BAM Nuttall, Morgan Sindall and Balfour Beatty Group – selected for the West contract; FLO JV – Ferrovial Agroman UK and Laing O’Rourke Construction – for the Central contract; and CVB JV – Costain, Vinci Construction Grands Projets, and Bachy Soletanche) for the East contract.

The infrastructure provider’s responsibilities will include managing the contractors who will construct the Thames Tideway Tunnel.