Dawlish wall
Council approves new sea wall at Dawlish, but campaigners believe it will have a negative impact on the resort.
NETWORK Rail’s plans to build a new sea wall at Dawlish were approved by Teignbridge District Council on April 16.
However, campaigners believe this could have a negative impact on the resort, claiming it is “likely to become another coastal town hemmed in behind a huge concrete wall with little appeal as a destination anymore”.
Construction can now begin on the 360-metre section between the Colonnade Underbridge (immediately west of Dawlish station) and Kennaway Tunnel. Work is due to start at the end of May, although it will stop during the peak summer season so as not to affect the main tourism period.
NR says the £30 million scheme will provide increased protection from extreme weather and rising sea levels for the next century. The plan is to construct a new pre-cast concrete sea wall in front of the existing wall. This new structure would be taller than the existing wall by a maximum of 2.5 metres and would incorporate a 1.1 metre-high pre-cast recurve (from the promenade level) along the top of the sea wall, to reduce waves over-topping.
The new pre-cast wall would be offset by approximately one metre from the alignment of the existing wall, and this will provide a wider public walkway which will be some four metres wide. The gap between the structures will be infilled with concrete.
At the base of the current structure, the existing concrete toe would be dug out and a new concrete strip foundation constructed. The new walkway would be approximately 1.6 metres higher than the existing one.
It is acknowledged that the higher structure will have an impact on views from Dawlish, and that from ground level the existing partially obscured view of the sea would be fully obscured. This will affect ground and basement floor occupiers, as well as businesses. However, the planning application warned that the loss of value to properties could not be considered when deciding.
“We know the local community in Dawlish feel strongly about the future of the sea wall and the resilience of the railway in their town. We’d like to thank them for their input and engagement with us so far,” said NR’s Western Route Managing Director Mark Langman.
“While developing our plans we have listened to the views put forward by the community. Our plan for the new sea wall will minimise its impact on Dawlish sea front, while providing the appropriate level of protection from extreme weather for the railway and the town.”
Langman said world-leading engineers have designed the plans, and that they had considered “hundreds of other options”.
Questions had been asked regarding the construction of a breakwater out in the English Channel, but NR explained in the planning application that any breakwater would need to be of such a height that it remains
effective during storms where elevated sea levels and long period waves combine to cause storm conditions.
To cover the next 100 years, this would need to consider: the tidal range variation at Dawlish, which can typically be as much as four metres (4.67m at its maximum) vertically between low tide and high tide; storm surges that can add a further one metre of height increase; a sea level rise by 2115 advised to be in the region of 0.75-1m; and the combined sea level variation between low tide and a storm water level that can be in excess of six metres vertically.
NR said that to be effective with this depth of water, a breakwater would need a minimum height of about four metres above the low water, which would place the crest at two metres above Mean Sea Level.
In a letter sent to Secretary of State for Transport Chris Grayling, local MP Anne Marie Morris, NR Chairman Sir Peter Hendy OBE and Teignbridge Council’s Planning Committee, Dawlish Beach Media Director Simon Deane called for a delay to the start of the work, claiming serious misgivings about the wall’s design.
Deane wrote: “Dawlish station has been the cause of the only weather-related closures of the main line since the collapse of 2014. The platform prevents the return of water to the sea and then floods the trackbed. Once the water level exceeds the height of the railhead a line closure is enforced.
“Our concerns with the proposed design is that a similar fate will be the result of this design. We are fully aware that the increase in height will not prevent overtopping when we experience an easterly gale, around high tide with winds in excess of 40mph. Waves are regularly photographed and filmed spraying over the top of Dawlish station, and we do not see how this could possibly be prevented.
“On average, Dawlish experiences these conditions three or four times during a typical winter season. The current design sees the waves sent skywards, and it is the spray that is then blown over by the strong winds. We believe that the current design will not prevent this phenomenon from occurring.
“If you accept that to be true, then the design preventing water from returning to the sea will in fact now force the excess water across the track bed and will drain into Marine Parade. We believe we are likely to see many more flooding events in Marine Parade as well as more closures to the main line itself.”
Deane concluded: “We are not requesting that nothing is done. Far from it! We are requesting that the plans are reconsidered and are put to a proper public consultation, rather than an information drop-in session. We have one chance to get this right but it has to be right for Dawlish and not just the railway connection to Plymouth and Cornwall. This is our heritage and future.”