Groundforce is providing crucial support for a project to replace a unique footbridge over the River Conwy in North Wales.
Local contractor MWT Civil Engineering is erecting a new shared-use pedestrian suspension bridge to replace the iconic “Sappers’ Bridge” over the river at Betws-y-Coed.
The original Sappers’ Bridge was built by Royal Engineers (aka ‘Sappers’) in 1917 but was later washed away by floods. It was rebuilt in 1930 as a slender iron suspension bridge by London-based David Rowell & Co and became known locally as “the wobbly bridge” due to its tendency to flex under load.
The bridge deteriorated over the years and was ultimately closed in 2021 due to safety concerns. But now, following public consultation, Conwy County Borough Council has enlisted MWT Civil Engineering to build a new 50m-long suspension bridge with two ornate towers in the style of the historic structure.
The new bridge will be wider than the original in order to be accessible to cyclists, wheelchair users, and mobility scooters.
Mass concrete plinths are required at the abutments of the bridge to carry the loads imposed by the cables supporting the suspended deck. Groundforce has supplied its modular hydraulic equipment to support the deep excavations that have been dug to accommodate these plinths.
“The excavation at the eastern end of the bridge was very challenging as it was set right next to St Michael’s church, built in the 14th century and the oldest structure in Betws-y-Coed,” says Groundforce area manager Jason Swift.
A live road alongside the churchyard and the close proximity of a number of protected trees further complicated the task. Adding to the challenge was the fact that the river at this point is wide and fast-flowing, and the water levels can change quickly depending on the weather.
In April 2025, Groundforce supplied equipment on the 1st phase to create the cofferdam for this complex excavation. Interlocking Larssen sheet piles were used to line the excavation with corner sections welded in to stop water ingress.
To drive these piles, Groundforce supplied two ICE8SG side-grip hammers to suit the length of the piles.
“It was the most appropriate hammer because its side-grip configuration allows it to safely and efficiently handle piles exceeding 6m in length,” explains Jason. “In comparison, a standard EMV lacks the vertical reach and handling capability.”
The sheet-piled cofferdam was supported with Groundforce’s Mega Brace modular beam with three MP50 hydraulic struts braced against the sides.
This operation was unusual in that an inclined ramp was excavated into the side of the main excavation to give MWT access to the bottom of the excavation. This allowed the contractor to take plant and equipment in and out without having to employ expensive lifting equipment.
The sides of the ramp were also lined with steel sheet piles and supported on either side with Groundforce’s Mega Brace beams.
MWT Civil Engineering has now completed the foundations and is currently working on the bridge abutments.
“We’re still in the ground, but will be off-hiring the Groundforce equipment in March,” says MWT’s contracts manager Wayne Tonks.
“Groundforce has been very helpful with problem-solving throughout the project. The design has had to change three times and Groundforce’s design team provided vital input,” he says.
The riverside location of the excavation meant a high water table with the resulting risk of water ingress. The use of interlocking sheet piles with welded corners was essential to keep the excavation free of flooding.