Fairlight Cove rock revetment stage I

In 1990, stage one of the coastal defence scheme at Fairlight Cove was completed. At Sea Road, a toe rock bund was the first sea defence to be built, which had a total length of 540m and ran from the eastern boundary of “Bishopsgarth” on Sea Road in the south west to approximately 110m east of the end of Steam Lane in the north east. Originally the bund was to extend for the full 1,500m of the Fairlight Cove frontage at risk. However, this was later reduced to the 500m as built plus an additional 300m to the west (at Fairlight Gap) later.

The design was for a 1 in 50 year standard of protection with rock armour stability designed for the 1:50 return period storm of 4.0m significant wave height and 7.8 second period. The construction of the toe berm consisted of 30-750kg core rock and two layers of 3-6 tonne armour rock with 3m wide crest berm at level +6.2m OD and slope of 1 in 3 to the foreshore and 1 in 1.5 backslope (with one layer of armour rock). It is understood that the rock was granite imported from Norway.

An inspection was carried out, prior to stage three of the works (2016) and confirmed that the toe bund was still performing well and had no obvious structural defects. There were a few rocks that had moved or been displaced but no sign of any significant settlement. Minimal rounding or cracking of rocks was found. A visual analysis of the structure by an engineer experienced in rock construction indicates that it is at about the correct placed density, in line with current practice as regards density, to be both structurally sound and with sufficient interstices to allow good performance with respect to wave breaking.