East West Rail - Further Critical Works

Engaging a supplier other than the East West Rail Alliance (EWRA) for this requirement, which is an extension of ongoing design services and works, would result in Network Rail receiving works and services which are different from and/or incompatible with those currently being developed and integrated with the MVLCW, and that incompatibility would result in disproportionate technical difficulties:

• The design services and works are an extension of ongoing MVLCW design development, access planning, consents, staging, timetable modelling, train path development, rail access strategy, rail signalling systems design, closure strategy, and physical interface management across the Marston Vale corridor and, they depend on continuous integration of the existing works and the required works which are the subject of this Notice. Given the overlapping design and delivery timeframes between the existing requirements and the new work, the remit requires integration of the MVLCW delivery plan with the wider railway works to minimise technical incompatibility, achieve design integration and manage delivery risks through interface studies, constructability validation, and coordinated staging plans. The difference in timing and compatibility would create disproportionate technical difficulties for Network Rail to manage. The network requires a near-term operational response to address network demand and without the successful completion and efficient integration of this work Network Rail would be required to operate a railway through a period of sharply increased demand without the planned capacity, service uplift, staging logic and supporting infrastructure.
• A new supplier would necessarily introduce different programme assumptions, design integration processes, interface management arrangements, and delivery sequencing. In practice, a separate supplier stepping into this live, interdependent delivery environment to coordinate effectively with the existing MVLCW supplier would create major interface risk, duplication of effort, resource and cost, delay in decision-making, and loss of programme efficiency. This would include duplication in critical documents such as WPP, CDM plan and engineering management plans which would be disproportionately inefficient and import more risks and complexities as well as additional overarching integration documents and additional duties. For engineering assurance, this would result in extensive progressive assurance plans, due to designs being developed at different stages and multiple design logs and risk assessments. With a new supplier, Network Rail would introduce higher safety and technical risks where two different suppliers are working in the same geographic area and delivering scope which cannot clearly separate the responsibilities and accountabilities for each supplier. The EWRA is already embedded in that interface and through asset protection design reviews and is therefore providing an integrated planning capability that would be difficult and inefficient to replicate through an additional supplier.
• A change in supplier would introduce non-compatibility between the current MVLCW BFO1B track restoration work and final state BFO1B to Fenny Stratford double tracking work. This incompatibility would lead to abortive works. With respect to signalling design, a new supplier would either introduce duplication of and inconsistent design parameters for alteration to signalling interlocking and control systems between current level crossing work and the scoped relock and recontrol of signalling systems or be solely reliant on a multi stage approach involving abortive works and unnecessary staging. Any overlapping design agreement for major signalling work – including the design, construction and testing with re-signalling, recontrols and relocking’s would cause disproportionate difficulties for Network Rail. Any risk delay to achieving the MVLCW works would also delay the enabling design, consents, seasonal works, access arrangements and physical interfaces on which the railway enhancements depend
• A different contractor would introduce the risk of delay to the new works and MVLCW itself caused by the overlap in design, planning arrangements and approvals from common interfacing parties and technical difficulties would arise because Network Rail would also be without the enabling works needed to support efficient construction, coordinated possessions, and the transition into the later access, closure and upgrade phases. That would create significant operational stress, including constrained timetable options, reduced resilience during disruption, greater pressure on existing stations and route interfaces, and increased complexity in maintaining assets while preserving future compatibility with the later Marston Vale interventions. It would also increase the risk of repeated access to the railway, abortive or duplicated works, and inefficient maintenance of assets that were intended to be altered, relocated or integrated through MVLCW and the follow-on enhancements.