Dear Sir
It is ironic that at a time when the BTS [British Tunnelling Society] is lobbying government on the economic and environmental benefits of underground construction, that the insurance industry is threatening to withdraw cover following the collapses at Heathrow and Hull [in the UK]. The latest CTRL incidents will not have improved the situation, though the reasons may be attributed more to the concept of tunnelling through East London rather than by questionable construction methods.
I believe this situation has arisen due to the requirements to put designs out to fee bidding. This has encouraged the use of design and construct contracts without engineering supervision by the designer and also the proliferation of tunnel design consultants who have no strength in depth and are unlikely to obtain it due to the lack of continuity in tunnelling projects.
As Alan Muir Wood pointed out in his letter, not only is good practice at risk by excluding the designer from the construction process, but costs are inflated too.
Yours faithfully
G R Heath MICE
