Network Rail engineers are carrying out emergency works tonight and tomorrow to bring Trowse swingbridge on the Norwich main line back into action.
The bridge is not currently operational after its system of computer controlled jacks and hydraulic pumps failed. These raise the structure and rotate it to allow river traffic to pass through. It is locked back into place to rejoin the track.
Network Rail has replaced some of the key hydraulic pipes and is currently completing the purge of the hydraulic pipes. This can only be done successfully by raising the 200t bridge, thus using the hydraulic system to push the air out.
Work will be carried out on Thursday and Friday night in order to do this and complete a number of successful lifts before returning it to service. This will hopefully be carried out by 9 June.
Trowse swingbridge is a unique and intricate piece of engineering and It is notable for being the only swing bridge in the UK to carry an overhead electrified railway track. These have to disconnect and reconnect every time the bridge opens. The overhead lines which carry 25,000 volts must join exactly in the right place to allow the current to pass through.