Station closures of the nature you refer to, are necessary due to the nature of the works undertaken, and to ensure that safety of passengers and the engineers working on site.
For example. the works carried out at Farringdon involved drainage and ballast replacement along the track, which required:
1. Prolonged, uninterrupted access to the worksite, and
2. Protection of the engineering team from live train operations.
Allowing passenger trains to stop adjacent to an active track renewal site would introduce unacceptable risks, including workers being exposed to passenger train movements, the potential for tools and materials to be within the swept path, and the inability to maintain a safe system of work. It was noted that there was no way of fire sheeting the shared accesses therefore it was safer to request the non-stopping of services. Closure of the station also makes engineers access easier as it allows tools, plant and materials to be stored at street level and brought down when required. Equipment of this nature would be much harder to use and store safely in an environment which remains open to the public.
We do not hold risk assessments for the decisions. The risk assessments we have are those for the engineering activities themselves (drainage, ballast renewal, access strategy, etc.). These assessments identify hazards to the workforce and specify that a protected possession without passenger operations is required as a control measure.
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