Coastal management in the 21st century: Coping strategies for vulnerability reduction

European coasts are coming under increasing threat as a result of climate change from erosion and flooding, with 20% of the coastline seriously impacted and 15 km2 of land lost each year (Doody et al. 2004). While coastal defences such as sea walls have been constructed since Roman times to protect human settlements from the sea, it is now increasingly recognised that these defences are unsustainable. The security provided by the 'hard' engineered defences has encouraged excessive development on the coast, and the defences themselves have led to the loss of intertidal habitat and the natural protection it provides. An alternative to maintaining 'hard' defences (hold-the-line) to protect land from increasing sea levels is managed realignment, where the engineered defences are deliberately breached. By allowing the coastline to recede to a new line of defence further inland intertidal habitat is created providing natural protection from flooding and erosion. In the face of rising sea levels and as existing coastal management strategies are being reviewed, it is pertinent to assess the economic efficiency of all methods of coastal defence. In this study, a cost-benefit analysis is undertaken in the Humber Estuary in North-east England, comparing a strategy of holding-the-line with various managed realignment scenarios. Cost-benefit analysis is viewed as one component of a wider policy appraisal process within integrated coastal management.