Any Cambridge Light Rail scheme would take time to resource and to implement. Much detailed advance planning is needed.
Opportunities to make substantial progress may exist with the Greater Cambridge City Deal, although owing to the particular financing mechanism adopted, at this stage it does not appear practical for progress to be made through this initiative. The City Deal requires demonstrable economic impact from measures undertaken, and this needs to be achieved over relatively short time horizons. Moreover, the City Deal has indicated that options that require substantial and long-term commitments, such as Light Rail, are not immediately up for consideration.
Cambridge Connect anticipates that expert work on technical and economic feasibility studies to develop a detailed set of realistic and properly costed options for a scheme would take at least a year. If commitments were made to start this work in 2016, the majority of feasibility studies could be completed in 2017. With subsequent commitments, detailed engineering design could commence by 2018, and it might be feasible to commence construction of the Isaac Newton Line in 2019/20 with a view to its completion in 2022/23. The other phases could be staged, or constructed in parallel, as appropriate and as finance and practicality allows. Cambridge Connect suggests that it could be realistic to complete a Cambridge Light Rail network by 2023 – 2031 depending on which phase or set of phases were taken up.
Crossrail tunnelling progressed at an average rate of ~38 m /day. If the underground component of Cambridge Light Rail was ~8 km, and we assume twin bore tunnels constructed in a similar manner to Crossrail, tunnel construction for the network could be completed in less than 18 months.
At this stage of conceptual development it is difficult to define a clear time-frame, which is subject to a wide range of influences, including the level of public engagement and support, political and institutional support, technical engineering, economic appraisal, financial mechanisms, and environmental and social impact assessments, to name a few.
Given the Cambridge Light Rail proposals are clearly longer-term by nature, and yet many needs are pressing in a more immediate time-frame, it is vital that short-term measures adopted by the Greater Cambridge City Deal have demonstrable benefits in themselves. However, we believe they need to be complementary to, and help facilitate achievement of, longer term goals. It is important that careful consideration is given to how short-term measures might support long-term strategies, and specific measures should not be adopted if they might impede or close off options that are more important in the wider strategy. Thus, while short-term improvements are needed, they should be aligned with a longer term strategy, as this will both enhance investments made and help to avoid waste of scarce resources.