Dales Marine Services was chosen for the project, which involved manoeuvring the gate, one of three at the Port of Leith, into the provider’s Leith dry dock for extensive refurbishment.  

Caisson gates are big, rectangular structures that - once a dock is flooded - float and are pulled into position before their ballast tanks are filled with water. 

Roughly every eight years, each of the Port of Leith’s caisson gates receives maintenance to make sure they are functioning properly.

The team from Dales Marine Services replaced all the timber on the gate and renewed wheel assemblies on two bogie systems, enabling the gate to manoeuvre on fixed rails. 

Steel repairs and the restoration of key valves were also carried out by the company’s specialists.

Phil McFadyen, operations manager at Dales Marine Services’ Leith shipyard, said: “Carrying out maintenance work on one of the Port of Leith’s three caisson gates is an important step in ensuring the hub’s continued safe operation. 

“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.”

Situated under three miles from Edinburgh city centre, the Port of Leith combines deep-water riverside access with large-scale infrastructure as well as development land to support energy, logistics and industrial activity. The port is owned and operated by Forth Ports Limited.

Chris Monteith, asset manager for the Port of Leith, said: “The Port of Leith is one of Scotland’s busiest ports and it is vital that we ensure that our infrastructure is operating safely and efficiently at all times. 

“We invest significantly in our maintenance programme in Leith, and it is essential that the gates are well looked after.”