A length of the tunnel built to carry a Tesco store over the railway at Gerrards Cross collapsed on the evening of June 30, 2005.  The area for the store itself is not affected.  The collapsed section is under part of the area being filled to make the car park.

This page illustrates the situation on the day following the collapse and also serves as 'home' for other pages related to the collapse.
You can go to the TescoTunnel home page here.

The recovery of the railway started on July 2nd. Pictures are here.
Some pictures of the clearance of the site between July 3 and July 10 are here.
The illustrated story of the work to make the railway safe again is told here

The finale is the resumption of train services on Saturday 20 August, told here.

By request, a diagram of the site has been added here,.  Use your browser's back button to return here.

July 1, 2005, 5.30am

A wide view of the collapse.  The steel work for the Tesco store is in the background.  Opinions expressed as to the reason include very heavy rain making the fill material very heavy and insufficient side filling before the top load was increased.

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The hole is quite dramatic.

The tunnel segments interlock with each other with a stainless steel facing.  The steel facing and the concrete behind it of the segment on the left seems to have been forced down, thus releasing the segment that should be present on the right.

A new vantage point and a small ladder have allowed capture of additional pictures of the collapse from the north side.

This is the wound, looking at the London end.  Where do you start to clear this lot?  Mounds of fill with 25 ton tunnel segments embedded in it, possible waiting to move if anything is disturbed.  Note the crater between us and the contractors where, presumably, a collapse has allowed fill to fall in.

Amid the mounds of fill material lie tunnel segments still with waterproof coverings still attached.  I think it is safe to say that this is the last of the segments to collapse in the domino effect that must have taken place.

The extent of the collapse is immense.  The tunnel remains are visible at left (just) and right.  The fill material from the sides has also collapsed adding to the heap that has fallen in from the top.

The broken end with almost surreal mounds of material.    Judging from the height of fill over the tunnel, this is presumably where the collapse started.

The edge of the material looks ready to slide into the space - probably relieve some of the pressure on the tunnel roof if it did.

Detail of the pressure plate between opposing segments.

The pictures that follow show the construction method, and may help to put the collapse pictures in context.

April 2005.  Heavy fill each side before top added.  Stitching beam framework and some completed concreting visible.

May 2005.  From the southern side.

I photographed the last few segments being placed at 2am on June 8th.  Despite some blur, the overlap and male/female connection is clearly visible.

After positioning the base of the segment, with careful precision, in the groove of the base, it is lowered towards its mate.  When it is within a few inches, the crane driver drops the segment hard against its mate.  The thump is considerable and in one instance I watched was repeated several times, seemingly to nudge the other segment into a better position.

 
Positioning the next segment in its base.  Just two men, with some serious size crowbars were able to position the 25 ton segment.

If the collapsed section is rebuilt, the whole damaged area will need to be cleared down to this level.  Possibly the foundations will need to be rebuilt if they have been damaged.

Return to the top here.

Version 6
May 30, 2006

(Links changed).