Aberdeen Beach Anti-Erosion Work
Background
Aberdeen Bay's coastline varies from densely populated areas with commercial and recreational amenities, to areas of outstanding natural interest. Within the bay is an active sediment system which responds to its surrounding environment - including wave energy from the North Sea, flow from the estuaries and intervention by man.
In 1999, a strategy study undertook an historical overview of the bay. In particular it examined past problems and analysed natural coastal processes and conditions (including waves, currents, water levels and sediment movements), together with their effects on the coastline and sea defences. The structural condition of the sea defences and the state of the coastline and its natural response to coastal processes were important elements of the work.
The study recommended a number of options for the continuing management of Aberdeen Bay. In particular it outlined that the line of defence to the far north as far as Donmouth should be maintained. This would be achieved by strengthening the existing defences and the maintenance and replacement of defence structures. For the remainder of the Bay, the study concluded that natural coastal processes should continue to shape the coastline.
Beach Erosion
Aberdeen's beach has gradually eroded over time. A result of natural conditions, this erosion has exposed the revetment sheetpile foundations. The erosion has accelerated as the sheetpile foundations have become increasingly exposed, due to waves directly reflecting off the seawall. With the impact of climate change, including rising sea levels, the rate of erosion is likely to increase further.
Analysis undertaken by geotechnical engineers has determined that levels on a section of Aberdeen beach are nearing a critical point – after which the revetment would fail. This would cause the loss of sections of the beach esplanade, and without intervention, lead to the loss of the road and buildings near to the coastline. In addition there would be the risk of contamination from old tip sites which are covered by the revetment.
Without remediation work, the coastline's erosion will continue - placing inland properties and infrastructure at risk.
