Humber Bridge
VolkerLaser is proud to have successfully delivered key maintenance works on the iconic Humber Bridge, working as the principal contractor on behalf of the Humber Bridge Board.
What we did
Opened in 1981, Humber Bridge stands as the UK’s longest single-span suspension bridge and is a vital link across the River Humber. Spanning 2,200 metres from anchorage to anchorage, its road deck sits 30 metres above the river. This Grade I Listed Structure is supported by two 155-metre-high towers, designed to account of the Earth’s curvature, with their tops positioned 36 millimetres further apart than their bases.
The project’s scope of work involved the relocation and removal of four underdeck inspection gantries as part of essential maintenance works. The Hessle Side Span gantry was hauled approximately 280 metres and lowered onto a trestle arrangement in the north anchorage compound for storage. The Hessle Main Span gantry was moved 50 metres into the estuary and lowered onto a barge for transportation. Similarly, the Barton Main Span gantry was moved 80 metres into the estuary and lowered onto a barge. Lastly, the Barton Side Span gantry was hauled 530 metres and lowered into the south anchorage compound, where it was dismantled and disposed of.
The initial phase of the project involved our rope access teams inspecting the central bolted splice in each gantry. Following these inspections, the gantries were transported to their designed lowering locations using a combination of tirfors and rigging systems. A lifting cradle was installed beneath each gantry, allowing them to be safely lowered using Tirak winches. The Hessle Side span was the first to be lowered and was placed onto trestles for retention by Humber Bridge Board. Subsequently, the Barton Side Span was lowered and dismantled using an excavator equipped with hydraulic shears.
Lowering of the main span gantries required the use of a 35-metre by 11-metre barge, supported by two tug vessels. Detailed planning and coordination were essential to ensure operations aligned with the morning high tide. This process involved close collaboration with the Port Authority, marine contractors, crane hire companies, and salvage yards, while factoring in weather conditions and tidal ranges.
Despite the complexity of working in a busy shipping lane with a 5-metre tidal range, our specialist team successfully completed the gantry relocations and removals within the limited working windows. To minimise disruption, all works were carried out from one side of the bridge’s footpaths, with the east footpath generally remaining closed to the public during operations. The bridge’s carriageway remained fully functional throughout the project, ensuring uninterrupted traffic flow for vehicles and pedestrians.
The project was completed to schedule and budget.
