Description of Works
FM Conway has been working with the London Borough of Southwark to deliver a complex refurbishment programme for St Saviour’s Dock.
Once a hub of Victorian commerce, today, the industrial buildings have been converted to modern London homes, with the bridge providing a crucial link over St Saviour’s Dock for residents and local businesses as well as for riverside walkers along the Thames.
The stainless-steel cable stayed structure was built in 1995 by the London Docklands Development Corporation before handover to Southwark Council.
Since opening, the bridge has been subject to various mechanical, structural and operational issues. To ensure there were no safety issues, the bridge was fixed in the closed position in recent years, preventing the passage of large boats into St Saviour’s Dock.
Now, the London Borough of Southwark in partnership with CONWAY AECOM, has carried out a project to refurbish the bridge, the opening mechanism and the timber jetty approaches. By carrying out these much-needed refurbishment and maintenance works, the project will enable passage for larger boats as the bridge was originally designed to.
Through a regular maintenance review, the Council identified the need for a comprehensive upgrade to strengthen the bridge and keep it safe for public use, including renewal of its distinctive sailboat rigging and repairs to its hydraulic swing system.
As Southwark’s term maintenance contractor, FM Conway was appointed to refurbish the bridge, its opening mechanism and timber jetty approaches, working with its partner AECOM.
The team has modified the bridge’s existing balustrade structures to accommodate the new design of the strengthening works. Ducting and cabling have also been installed for a new power system for the swing mechanism.
Louise Chenery, a civil engineering apprentice in the team, has been helping to procure a 40mm veneer for the timber piles that support the bridge’s two timber approach jetties.
Louise Chenery, Civil Engineering Apprentice at FM Conway, explains:
“The water damage to the wood is cosmetic rather than structural. Our job has therefore been to find a suitable material for wrapping the existing timber, keeping the bridge looking ship-shape!”
Kevin Brown - Contract Supervisor at FM ConwayPiling in a river environment brings its own special considerations, including soil conditions, tidal patterns and wind conditions. We also had to allow for bow waves up to one-metre high and the pressure that this might put on the scaffolding structure.
The main issue affecting the works was that the bridge needed to be closed for the duration of the project, therefore it was necessary for pedestrians to follow a marked diversion via Shad Thames and Mill Street.
This meant residents and local stakeholders would need to be regularly updated throughout and the team ensured that this was a priority. This activity was led by FM Conway’s Public Liaison Officer, Helen McConnell, who has been working closely with residents’ groups to keep them informed.
However, before any works could begin, Contract Supervisor Kevin Brown and his team needed to ensure the area was safe to work in. Like many historic parts of London, this meant checking that there was no unexploded ordnance in the area. With this confirmed, the next step was to install the screw piles for the scaffolding from which the team would work, while cooperating closely with the Port of London Authority and Environment Agency.
Kevin Brown, Contract Supervisor at FM Conway, said:
“Piling in a river environment brings its own special considerations, including soil conditions, tidal patterns and wind conditions. We also had to allow for bow waves up to one-metre high and the pressure that this might put on the scaffolding structure.”
The final stage of the process will see FM Conway collaborating with a specialist rigging supplier to re-rig the bridge.
Kevin adds: “It’s a finely tuned process. The rigging needs to support the weight of the structure to allow the swing system to rotate the bridge through 90 degrees. To do this, we’ll mount load cells on each of the rigging strands, tensioning them to the right Kilonewton load specified by AECOM’s engineers.”
Due to the extent of the required repairs to the famous bridge, it was originally thought that the council would look to replace the structure entirely. However, FM Conway’s work has ensured that the award-winning bridge can retain most of its former self.
Now the bridge has been successfully refurbished and reopened, avoiding the need for pedestrians to take a half-mile diversion via Dockhead.
A recent council report confirmed that although works had taken longer than planned, they are expected to be completed within budget.