There is something odd about this.
The lorry with the low loader was apparently going slowly along the hard shoulder.
It has clearly passed under the gantry sign just before it.
The footbridge is a curious design with a narrowing section to allow a slope on the bridge while keeping the bottom flat and set height above the carriageway.
It would seem that the bridge section just rested on the pillar and on the midway joint.
In terms of backing up that is what happens normally. However, the location here was odd. The London bound carriageway was not far from a junction and was cleared. The southbound carriageway - the one with the bridge still standing is just beyond a complex motorway junction which made it very difficult to reverse traffic.
In the end they decided that the bridge left standing was secure and allowed traffic under it.
Motorway was closed for a day and a half.
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