Before and after: Major maintenance completed on port gates

One of the Port of Leith’s three massive caisson gates has undergone major refurbishment as part of an eight-yearly maintenance programme designed to keep vessels moving safely through the locked harbour.

The gates play a crucial role in the operation of the Scottish Port of Leith, creating a watertight barrier between the harbour and the tidal waters outside. Each gate is taken out of service for maintenance approximately every eight years to ensure its mechanical and structural components remain in proper working order.

The latest programme of work involved bringing one of the gates into dry dock for a comprehensive overhaul.

Caisson gates are large rectangular structures which float when the dock is flooded before being positioned in the lock. Their ballast tanks are then filled with water, causing the gates to settle onto underwater rails. The gates can then move along the rails as they open and close, helping maintain a constant water level within the non-tidal port.

The refurbishment included replacing all the timber on the gate, renewing wheel assemblies on two bogie systems and carrying out steel repairs. Key valves were also restored to ensure the gate can continue to operate effectively.

The work was carried out by specialist marine engineering company Dales Marine Services at its Leith dry dock.

Phil McFadyen, Operations Manager at Dales Marine Services’ Leith shipyard, said maintaining the gate was important to the continued safe operation of the port.

“Because the port is locked and non-tidal, the gate is what allows vessels to enter and leave and, if it were to fail, that access would be lost,” he said.

The Port of Leith, owned and operated by Forth Ports, is one of Scotland’s busiest ports and its infrastructure supports energy, logistics and industrial activity.

Chris Monteith, Asset Manager for the Port of Leith, said regular maintenance was essential to keeping the infrastructure operating safely and efficiently.