RAIB report into Northern City Line tunnel drill bit incursion

[Beeyar Wunby]

Yes the RAIB report is out. Linky here....Northern City Line report

This is the line of the original Moorgate Disaster.

It seems incredible that this could happen in the heart of London, but then as we say on the railway - "if it can happen, it WILL happen eventually".

If you remember what happened, a train driver spotted water pouring from the roof of the single bore tunnel and reported it to the signaller. The bobby cautioned the driver of the following train and told him to inspect the line - he managed to stop short of two wapping great drill bits lying across the the 3rd rail and a running line.

This is one of the busiest commuter routes into the heart of London, and the Class 313 stock is some of the oldest in the country. The derailment of a full train would certainly have caused significant injuries and possibly fatalities. Rescue operations in the tight single-bore tunnel would have been very difficult.

A construction company was piling in preparation for building a 7 storey block of flats, and NOBODY was aware that there was a tube tunnel 13 metres below.

The investigation outlines a whole comedy of errors and 'not my job, guv' attitude of local government and the building industry. Because the line doesn't appear in OS maps, and belongs to Network Rail and not TfL it was forgotten about in all planning applications and searches.

Originally Posted by RAIB report

Immediate cause
Piling operations penetrated the tunnel lining and obstructed the track

Casual factors
a. The client did not appreciate the significance of an entry in the Land Registry Property Register

b. searches undertaken on behalf of the client prior to it purchasing the site did not include Network Rail

c. a 1967 undertaking by the London Borough of Hackney, intended to give the tunnel owner the right to approve any proposed development did not result in Network Rail being consulted before piling commenced

d. the structural engineer and contractors did not identify that an obstruction found in an exploratory borehole was was part of a railway tunnel

e. pre-constrution documentary searches did not detect the presence of tunnels, or the need for additional searches

f. the planning approval did not recognise the tunnel risk

I guess this is a product of the 'modern way'

1. The buck being passed round different consultants
2. Everything being done in a hurry
3. Everything being done at the cheapest quote rather than comprehensively

Thank goodness nobody was hurt.

[Tony]

I do hope that the developers get the bill for the tunnel repairs. It is their responsibility to ensure that all possible checks have been carried out. They probably have a good case against their legal advisers for negligence.

[jayar]

What an amazing report, and hopefully all recommendations are incorporated - thank you for posting, Beeyar Wunby.

[D.O.G.F.A.N.]

If you want to see these reports just log into the RAIB website and they will send you every report with no spam or adverts. Easy.
Stuart

[pbowler]

Its a good thing it happened really, just think what the outcome might have been if the 7 storey block had been built putting all that extra loading on top of the tunnel. Instead of a relatively minor incident there could have been a major disaster!

[Beeyar Wunby]

Originally Posted by Tony

I do hope that the developers get the bill for the tunnel repairs. It is their responsibility to ensure that all possible checks have been carried out. They probably have a good case against their legal advisers for negligence.

Yes - anybody who has ever bought a house knows the importance of paying to have a throrough search carried out before you part with your hard-earned cash. Otherwise you could be buying a monster.

I guess that whoever did this search will find themselves being sued by the development company. The Moorgate line tunnels (GN side) were built 110 years ago, and since then it has not been feasible to sink piles very far into the ground on this property. Considering that the rail tunnel is 13 metres below the surface and the structural engineers want to drive piles down to 21 metres, it rather looks like the project is essentially a lemon.

Does anyone know a good firm of litigators ?

[pbowler]

Looks like the only people that are going to make a profit on this project will be lawyers.