Scour and Accretion Monitoring Services for the Thames Tideway Tunnel

The Thames Tideway Tunnel (TTT) is a major infrastructure project, urgently needed to protect the tidal River Thames from increasing pollution. London’s sewerage system is no longer fit for purpose and spills tens of millions of tonnes of untreated sewage mixed with rainwater (combined sewage) into the tidal reaches of the River Thames every year. Bazalgette Tunnel Limited (BTL), is the licensed provider set up to finance, build, maintain and operate the Thames Tideway Tunnel. From Licence Award BTL trades and is known to the public as 'Tideway'. Following completion of the main tunnelling works, it is necessary to undertake scour and accretion monitoring services (bathymetric surveys) of the foreshore to monitor for unexpected impact on scour and accretion within the River Thames. The purpose of the services is to establish the foreshore profile and natural variations of the foreshore following construction works in the foreshore when operation of the TTT commences. The surveys are to be of designated areas and repeated to determine variations between surveys. The TTT works in the foreshore have the potential to affect the river regime, causing variations in the riverbed levels greater that natural variations and may affect the natural habitat. Scour of the riverbed can be detrimental to the stability of third-party infrastructure such as river walls, jetties and bridge piers, whereas accretion of the riverbed may impact navigation and could affect drainage outfalls. It is anticipated that a supplier will be procured to deliver the services (across multiple project TTT sites / locations) pursuant to the award of a single contract. The contract is expected to commence in March 2025 allowing for a period of supplier mobilisation, with Services due to commence in June 2025 up to a period of six years. Please note this period is subject to change. The duration of the requirement will ultimately be determined by ongoing analysis of the River Thames and associated scour and accretion levels. Interested parties must register on Tideway's e-sourcing portal and will be able to download the Pre-Qualification Pack ('PQP') including the form of response to be completed and returned to submit a compliant response. The registration process is set out in section VI.3) of this Contract Notice. The PQP contains further detail regarding Tideway, the scope of services and further detail on the Contract and the timeline and phases of the procurement. Whilst it is intended that the procurement will be run in accordance with the timeline and process described in the PQP, this contract notice and the Procurement Documents, Tideway reserves the right to amend or cancel any or all of the procurement at any time and/or amend the timescales.