Opened in 1886, the Mersey rail tunnel carries the Merseyrail line under the River Mersey between Liverpool and Birkenhead. Working with rail infrastructure of such an age poses many challenges – both technical and health and safety.
As part of the redevelopment of the Museum of Liverpool, which was taking place on the surface above the tunnel, MJ Rees surveyed a 265m section of the tunnel system in two separate site visits, including the main tunnel and Mann Island Junction, plus the drainage and ventilation tunnels. The survey was plotted onto OS National Grid and datum.
This required transferring control from the surface. Due to the nature of the site, this entailed traversing along the tunnel from the Birkenhead side, through the survey area, then up to the surface on the Liverpool side over five nights of work.
Detailed safety procedures, risk assessments and method statements were agreed with the project managers and consulting engineers before commencing work on site, taking account of all safety factors.