If you’re doing some DIY at home you might move furniture out of the room, or put a dust sheet over it, to protect it while you’re hard at work (in a similar, but less technical, way to our dust mitigation measures). During the Rochester Bridge Refurbishment Project, lead contractor FM Conway has to do a similar thing, taking care of the assorted infrastructure around the bridges.
One specific piece of equipment that needs to be protected is located at the Strood end of the New Bridge, where people may have spotted a pair of large green boxes. These contain equipment belonging to Southern Gas Networks, to enable them to monitor their gas pipes.
The boxes sit at the bottom of a short soil slope, at the top of which is the bridge, which puts them at a small but easily managed risk because they need to be protected from any debris created by nearby activities.
We’ve therefore installed a gabion wall. This is essentially a wire cage (the word ‘gabion’ comes from the Italian ‘gabbione’, meaning ‘large cage’), which contains large pieces of rubble.
So why did we choose a gabion wall instead of a solid concrete structure?
It’s a sustainable option. Compared to a concrete wall of the same height, a gabion wall has an 80 per cent lower carbon footprint. Vegetation can also become established in the gaps, which further contributes to carbon sequestration over time and will soften its appearance much more than if it was a plain concrete structure.
The area has also been sown with an appropriate grass seed mix to make it look a little more pleasant and hospitable for nature. Once the works are complete and all risk of damage has gone, the area will be re-seeded.