Sir: We have heard that London Underground is proposing to repair Brunel's Thames Tunnel by "shotcreting'' [lining the tunnel with concrete], but there is a grave concern about spoiling its civil engineering heritage value through marring its interior appearance, as we know from your newspaper and from information supplied by Professor Paxton of the Institution of Civil Engineers.
The Thames Tunnel is both the first shield-driven tunnel and the first underwater tunnel bored through soft ground in the world. In addition, the tunnel has been used for over 150 years. We express our gratitude to our predecessors for their efforts to save this tunnel, and it is our earnest wish that its original style be preserved intact for ever.
The shield tunnelling method is still being developed. It isthe most important technique for underground construction, and it is extensively applied in Japan. Traffic safety should be secured, but repairs should be done by a method that is not likely to spoil the tunnel's appearance. We are of the opinion that the shotcreting should be reconsidered, in the hope that the tunnel will be listed as top-class heritage.
Committee of Historical Studies
in Civil Engineering
Japanese Society of