Construction of this next section of the £80 million (US$106 million) upgrade will take around two years to complete and follows years of detailed studies, designs and joint working between world-leading marine, coastal and railway engineering experts.
The first part, from Dawlish station to the Coastguard breakwater east of the station is expected to be completed in late 2021. The final part between the station and the Colonnade breakwater, which will link up the new wall at Marine Parade, will start to be built shortly after.
A major aspect of this work involves the use of an innovative eight-legged, self-contained walking jack-up barge, Wavewalker. The Wavewalker is only one of its kind in Europe and it will be the first time this type of barge has been used to maintain the UK rail network.
This innovative piece of equipment will be used by contractors BAM Nuttall to safely access the sea face of the railway embankment along Marine Parade and help deliver the piling at the sea wall. The Wavewalker benefits from being able to operate across high tidal ranges that particularly impact the south Devon coastline, that would otherwise restrict the number of hours it is possible to safely work on the sea wall.
The piling rig which is being operated from jack-up barge is a Delmag RH34 rotary bored piling rig. It has been supplied by ABI Equipment Ltd and the company is also responsible for the operators that are running it 24/7 across a four shift pattern.
Once complete the 415m section of new sea wall will be higher than the existing wall; have a curved edge to send waves back towards the sea; have a high-level, wider and safer promenade; pedestrian access to the beach and an accessible station footbridge with lifts.
As part of Network Rail's commitment to spending money locally, the scheme will also deliver an important boost to the south Devon economy with as much as £10 million expected to be spent with local businesses during the second phase of work.
This follows the £5 million spent on local labour, materials and accommodation during the first section of the new sea wall, which was completed earlier this year.
Huw Jones, divisional director rail, BAM Nuttall said: "The railway in Dawlish is uniquely positioned, leaving it enormously exposed to the worst weather that the English Channel can produce. Working in this environment requires imaginative solutions and innovative thinking and our use of Wavewalker is a great example of that.
"The jack-up barge allows us to work safely on the foundations of a new sea-wall on a 24-7 basis, regardless of tides. Using the Wavewalker to deliver this phase of work means we can complete the work more cost-effectively, allowing us to minimise impact on passengers whilst significantly reducing the time that this work impacts the local community."
Ewen Morrison, Network Rail senior programme manager for the Dawlish sea wall project, said: "We are thrilled to have started work on delivering the next section of this vital upgrade that will protect the rail artery to the south-west for the next 100 years. Our plans have been drawn up by world-leading engineers and it will provide greater protection to the railway and town from rising sea levels and extreme weather. We will continue to update the community with how our work is progressing."
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