Local contractor MWT Civil Engineering is erecting a new shared-use pedestrian suspension bridge to replace the Sappers鈥� Bridge over the river at Betws-y-Coed.
The original Sappers鈥� Bridge was built by Royal Engineers (hence its name)) 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 鈥渢he wobbly bridge鈥� due to its tendency to flex under load.
The bridge deteriorated over the years and was ultimately closed in 2021 due to safety concerns. Last year Conwy County Borough Council awarded MWT Civil Engineering a 拢3m contract to build a new 50-metre-long suspension bridge with two ornate towers in the style of the historic structure.
The new bridge will be wider than the original 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.
鈥淭he excavation at the eastern end of the bridge was very challenging as it was set right next to St Michael鈥檚 Church, built in the 14th Century and the oldest structure in Betws-y-Coed,鈥� said 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 first 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.
鈥淚t was the most appropriate hammer because its side-grip configuration allows it to safely and efficiently handle piles exceeding six metres in length,鈥� Swift explained. 鈥淚n comparison, a standard EMV lacks the vertical reach and handling capability.鈥�
The sheet-piled cofferdam was supported with Groundforce鈥檚 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鈥檚 Mega Brace beams. 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.
MWT Civil Engineering has now completed the foundations and is currently working on the bridge abutments.
Contracts manager Wayne Tonks said: 鈥淕roundforce has been very helpful with problem-solving throughout the project. The design has had to change three times and Groundforce鈥檚 design team provided vital input.鈥�
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