Due to erosion by wind, waves and rising sea levels, the beach front at Eastbourne needed to be reinforced. The previous campaign to improve coastal defence was carried out in 1998 and in 2011 the shoreline no longer fulfilled the design criteria for safe coastal protection.
Eastbourne Borough Council (EBC) developed a scheme comprising the recycling of existing material, particularly in environmentally sensitive areas (SSSI – Beachy Head) and the importing of bulk quantities for the rest of the beach frontage.
The sequence of the works was to execute the recycling first and subsequently fill the groyne bays to the required profiles with imported shingle.
The site stretched over a total length of 5.5 km, from Beachy Head in the west, along the whole of Eastbourne front, to Langney Point in the east. The design profile varied over the length of the site, with the aim of achieving a design crest width and height with seaward slopes of approximately 1 in 9.
All dry earth moving was subcontracted to Ovenden who executed the works with up to 3 excavators, 4 bulldozers and 10 dump trucks working at the same time.
The imported shingle was mainly dredged at Owers Bank /Area 435. The material supplied complied with the design requirements, having a D50 in the order of 16m.
As this material had to be pumped ashore via an 1100m long sinker line, a heavy duty dredger with substantial installed power was needed. The Prins der Nederlanden was therefore mobilised, with a total of 19,000 kW installed capacity, every one of which was required during pump ashore.