On Two Bridges

I’ve blogged about Wirral’s Four Bridges which cross the Birkenhead dock system before (see my article ‘On Four Bridges’ at the attached link: https://briansimpsons.wordpress.com/2013/08/31/on-four-bridges-around-birkenhead-docks/)  Work has been on-going to replace two of the four bridges and last Thursday the two new bridges that link Alfred Dock and the East Float in the docks between Birkenhead and Wallasey finally opened to the public some six months after the original target opening date.  There has been no through traffic along Tower Road, which goes across the docks between the two towns, since the end of March last year.

The two old bridges were replaced because of outdated features including height and weight restrictions and they were requiring more frequent and costly maintenance works to keep them functioning.

The works saw the “C” bridge which is the bridge closest to Wirral Met College – replaced by a new structure.  Most motorists will drive across it now without knowing it’s a bridge, the old ‘girder’ style bridge has been replaced with an uninteresting flat crossing with a set of protective barriers either side, technically called a flat deck bridge.

There was more complex work to replace the “A” bridge, the lifting bascule bridge which allows ships access to the Wirral docks from the River Mersey.  It was originally expected to take until the New Year to complete but technical difficulties were encountered.

I’ve taken images from when the old bridge was in place and during the replacement works as well as today of the new structures.

Before…

During…

After…

The initial delay to the project completion was caused by the discovery of an obstruction behind the dock walls – uncovered during excavation work – which meant the permanent foundation for the new ‘A’ bridge had to be moved.

Then in February the planned ‘floating-in’ of the new structure had to be postponed due to snow.  With that part of the project requiring a full closure of the docks to shipping for a week, the earliest this could be rescheduled with dock owners Peel Ports was April.  The replacement lifting bascule bridge was lying in wait in the contractor Dawnus Construction’s yard on Dock Road during this time.

Since the bridge was successfully moved into place in April, contractors have been completing the remaining works and putting the structure through testing.

Both the original bridges were constructed around 1931.  The original steel truss opening bridge (the A bridge) has been replaced with a new semi-through steel box girder single leaf rolling bascule bridge built by Dawnus Construction from Swansea.

The original fixed truss bridge has been replaced with a new pre-stressed-reinforced concrete composite flat deck bridge.  The other works completed were the highway improvements including improved facilities for pedestrians and cyclists.

As for the ‘A’ bridge I have taken photographs of the original ‘C’ bridge as well as during the construction work and following the installation of the new structure.

Before…

After…

During…

I have to say when you compare the new structures with the original bridges they have very little architectural merit, they are modern and functional but lack anything to get your heart racing.  The original structures were landmarks their replacements are not unfortunately.  The new opening bridge looks odd with no wider supporting structure around it.  The original bridge was a product of its time when British engineering was still world famous and the industrial revolution was in its last throes.  I suppose the new one is a product of its time too.

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