An Assessment of Accommodation Strategies for Coastal Adaptation in Cape Town, South Africa, in Response to Climate Change

[摘要] ENGLISH ABSTRACT:As the world finds itself increasingly unable to avoid the negative impacts of the physical phenomena associated with climate change, adaptation to climate change has been brought to the forefront of the international agenda. The range of adaptation technologies available can be categorized into three basic strategies (IPCC, 1990): Protection, (managed) Retreat, or Accommodation.The practice of adapting existing developments and infrastructure in the coastal zone by the process of accommodation has not yet seen wide implementation as a formalised adaptation strategy. In order for a community to accept and successfully implement accommodation strategies, all community stakeholders are required to accept and live with a certain level of managed risk, and to also rethink the concept of failure. As a result, accommodation practices implemented globally have been closely related to fields such as risk - and disaster management. Structural innovations in the field of accommodation measures include advanced technologies to elevate existing buildings safely above flood levels, and even 'amphibious houses.In Cape Town, South Africa, the choice between protection, retreat or accommodation as an adaptation measure remains complex. Not much discussion has yet been generated concerning accommodation measures that could be implemented to reduce the risk to existing properties that are already inappropriately located in the risk zone (e.g. seaward of the coastal hazard line), by accommodating the dynamic coastal processes taking place.Accommodation has been found to be most feasible in Cape Town at case study sites with a stable, non- or slowly eroding shoreline, which are also subject to flooding. The elevation of buildings and the alteration of buildings for flood-proofing, in unison with proactive risk and disaster management, could be implemented to accommodate the impacts of flooding on affected infrastructure.Located on Cape Town's Atlantic Seaboard, Bakoven serves as a case study sample of such a site where an accommodation-based adaptation solution could be feasible. Both global and regional downscaled climate models have been found to deliver a large range of future climate conditions. Assuming best estimate future predictions, Bakoven properties have been found vulnerable to extreme flooding during both status quo and future extreme events. Environmental conditions at Bakoven are favourable for the construction of piled foundations. Stringent environmental and heritage constraints imposed by local government would, however, render accommodation strategies unviable.It is recommended that government at all levels be willing to adopt a more flexible approach to governing coastal areas, to ensure that the regulations they impose remain as dynamic as the environments which they govern. The viability and possible benefits of accommodation measures, rather than protection or retreat approaches should be carefully considered on an individual case-by-case basis, in unison with the local community.

[发布机构] Stellenbosch University