The Manchester Ship Canal opened in 1894 and connected Manchester to the coast at the Mersey estuary near Liverpool. This enabled Manchester to become Britain’s 3rd busiest port even though it is 64 km inland.
The canal can accommodate sea going vessels with a maximum length of 183 metres but by modern standards this limits the size of ship that can access the port. The main port at Salford Quays closed in 1982 for commercial handling and ships now dock on canal side wharves.
However some boats do still use Salford Quays including pleasure cruises between Manchester and Liverpool, hence the need for any bridges on the canal to not restrict the ships passage.
After Salford Quays closed the area around about became derelict but has since become the largest urban regeneration project in the UK. The site has been developed with a mixture of housing, offices, theatres, museums and retail outlets. It is also served by the Metrolink tram system.
The latest phase of the development has been the building of Media City that is the site of a number of TV and radio companies including a number of BBC departments that have moved from London.
The Lowry bridge was originally erected when the Lowry Centre was built. This was a modern art gallery, theatre and arts centre. The bridge gave access from the south side of the canal. At a later date the Imperial War Museum North was opened on the south side of the canal, linking both sites together.
This
website provided these technical details of the bridge.
"The superstructure weighs 220 tonnes and the towers 150 tonnes. In its open (to pedestrians) position the bridgespan sits at low level, providing a 5.08 metres clearance to the canal. When raised for the passage of shipping, the soffit of the deck is at
the statutory height of 22.9 metres above the canal water level.
Span supports are located back from the water's edge, thereby avoiding any interruption to water flow, navigable width, or change in water level. The bridge span comprises a pair of steel bowstring arches of 96 metres overall length, and 91.2 metres span between bearings.
The arches are at 10.9 metres spacing at the bearings, and meet over mid span, where they rise to a height of 11.2 metres above the surface of the deck. The span is lifted at its four corners by hydraulically driven winches, with cast steel counterweights provided at each lift
point to minimise mechanical effort.
The four towers stand at a height of 31 metres and each support a pair of high level sheaves, which carry the ropes connecting the deck and
counterweights."