Ferry swing bridge

  • Frerry Swing Bridge

Lead Partner: C Spencer was the principal contractor.

Project History
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Old Kilpatrick to Dumbarton, Old Kilpatrick


The swing bridge was built in the 1930s by Sir William Arrol. It had been out of use since the early 1960s.

During 2000 and 2001,  the bridge was refurbished and new mechanical, hydraulic and electrical systems fitted to make it fully operational again, allowing canal traffic through.

The bridge carries a single carriageway road (with external cantilevered footpaths on both sides) over the Forth and Clyde canal and has a nose span of approximately 13.2m and a tail span of 6.4m.

In order to refurbish the bridge it was necessary to remove the main pintle bearing for inspection and refurbishment. This involved raising the bridge (weighing 300t) approximately 1000mm vertically to allow the bearing to clear the main bridge beams. The bridge was raised over a period of 24 hours prior to removing the pintle. Once the pintle was removed the bridge was lowered back down to road level onto timber hardwood and steel packing bearers. This enabled the bridge to be re-opened to road traffic whilst the pintle was refurbished and other contracted works continued.

A further technical aspect of the works was the redesign of the road junction and associated traffic light system. The bridge operates on a simple control panel whereby the bridge operator merely presses a button to commence the opening sequence.

Current status:

The contract is complete. Other minor works to the bridge included the repainting of the bridge superstructure and refurbishment of the control housing.


The work was completed between September 2000 and March 2001.


The contract was valued at approximately £650,000