Pictures of Dawlish show there are few, if any, groynes which allows the sea to erode the sea wall.
Looking around Tendring in North Essex, some places have well designed and maintained groynes – and a good beach with lots of dry sand in front of the sea wall.
The level of sand dropping and
the sea wall failing like this
So the failure of the sea wall at Dawlish is no surprise.
Do you think this was