Structural stability of the seawall

The seawall around the Spa dates back to the 1840s and is in a deteriorating condition. 
Problems include undercutting of the toe, cracking and loss of joint material, voiding behind the seawall and displacement of masonry blocks, all affecting the stability of the wall.  Every year maintenance work is needed on the seawall to repair damage.
The seawall plays a key role in the stability of the cliff behind, preventing erosion of the toe of the cliff which would steepen the cliff further and inevitably lead to large scale landslips.