Thames Tideway Tunnel - C405 Main Works West - Acton Storm Tanks - Drop Shaft Secondary Lining Slipforming

The Thames Tideway Tunnel project (the Project) will control CSO discharges by intercepting and diverting combined sewage flows into a new storage and transfer tunnel.

The main tunnel will run from Acton Storm Tanks in west London to Abbey Mills Pumping Station in the east, where it will connect to the Lee Tunnel, which will transfer the combined sewage to Beckton Sewage Treatment Works for treatment.

The Project extends from Acton Storm Tanks in west London, to Abbey Mills Pumping Station in east London.

The Project includes associated works at Beckton STW, Shad Thames Pumping Station and Bekesbourne Street.

The Project comprises: a. tunnels: i. a main tunnel which will capture and store combined sewage from CSOs along its route and transfer it to Abbey Mills Pumping Station, from where the Lee Tunnel will transfer it for treatment at Beckton Sewage Treatment Works ii.

11 connection tunnels, which will link flows from CSOs to the main tunnel. b.

Worksites: i. five main tunnel Worksites (drive and/or reception sites) ii.

16 CSO Worksites iii. two System modification Worksites Thames Tideway Tunnel iv. works at Beckton Sewage Treatment works.

Section 4: Scope of Works Construction of a secondary lining to a 30m dropshaft, casting of the vortex drop tube, and internal walls at Acton Storm Tanks.

The site is situated in Ealing, West London.

These works are to run concurrently with other BMB areas of works including hydraulic structures works.

Full welfare facilities will be provided to all subcontractors.

The scope of works includes supply of concrete and provisions of which to carry out the secondary lining.

This will require consideration for sequencing alongside the site wide programme.

The slipforming operation will be given priority for logistics and laydown areas during this time.

The subcontractor will have to take into consideration ducting (condensation drainage and ventilation ducting) that enters the shaft is required, including but not limited to waterproofing detail and casting in.

The Subcontractor shall be responsible for design and supply of any temporary works slipform shutter required for construction of the secondary lining of the shaft, baffle walls and casting in the vortex drop tube structure.

Returned quotations will be evaluated by BMB JV's (BAM Nuttall, Morgan Sindall PLC & Balfour Beatty) Procurement team in conjunction with our design and engineering teams.

Quotations will be evaluated based on; Cost Timeliness of return Adherence to and demonstration of understanding of the drawings and specifications provided at this point.

Provision of accurate product specifications to accompany the quotation.

Supplier experience of similar projects,evidence of this will be requested should the initial quotation be of interest.

Should the candidate supplier be shortlisted they will then be contacted dir