One of the most challenging coastal rehabilitation projects in North Ayrshire, the Saltcoats seawall rehabilitation scheme protects 850 metres of coastline from coastal erosion and wave overtopping, minimising railway line closure while also improving tourism by enhancing access to the beach.
We provided several engineering services including the optioneering design and subsequent detailed design of the coastal defence and adjacent promenade. Innovation was key in determining the repair and upgrade options to suit the contractor’s method of construction, and to keep the programme as short as possible. This included injection grouting behind the existing quay wall for void filling and to increase the factors of safety for stability. This meant that wall stability could be maintained, while the height and volume of rock armour on the seaward side of the wall was significantly reduced. This decreased the need for stone required for the scheme, which helped achieve significant savings.
Our design included a rock revetment to dissipate wave energy and a wave recurve unit on top of the existing wall which increases the height of the wall to reduce wave overtopping. We identified a disused quarry on the west coast of Scotland where supplies of between three and six tonne of rock armour were available. The quarry was re-opened and the armour stone was supplied to Saltcoats, resulting in a 20 percent cost saving from reduced haulage costs.