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The combined action of waves, surges and tides can cause flooding, erosion and dune and structure overtopping in many coastal regions. Addressing emergency and risk management in these areas require a combination of targeted campaigns and real-time data that measure all phenomena at stake and can be used to develop comprehensive monitoring platforms. These monitoring platforms can support the development of prediction tools that address all hazards in an integrated way. Herein, we present a methodology focused on multi-hazard coastal alert and risk, and its implementation in a tailored WebGIS platform. The MOSAIC platform offers a one-stop-shop capacity to access in-situ and remote sensing data, and hydrodynamic and morphodynamic predictions, supported by numerical models: SCHISM and XBeach. Information is structured on a local observatory scale, with regional forcings available for the correct interpretation of local hazards effects. This implementation can be further applied and extended to other coastal zones. The MOSAIC platform also provides access to a detailed database of past hazardous events, organized along several risk indicators, for the western coast of Portugal. The combination of features in the platform provides a unique repository of hazard information to support end-users for both emergency and long term risk planning actions.

The purpose of this paper is to present the multidisciplinary approach adopted to undertake a detailed coastal flood and erosion risk management investigation at Cloughaninchy beach (Ireland). The site was severely affected by a series of extreme events with extreme high tide combined with a severe sea swell and onshore winds resulting in severe damage due to flooding and wave action as well as substantial retreat of the dune system. Based on a comprehensive assessment and multidisciplinary studies an appropriate plan was subsequently developed to best manage the risks identified and to further assess the feasibility of the recommended management plan options and measures. The project is an example of how vital the integration of specialized disciplines (coastal engineering, hydraulic flood modelling and coastal morphology) is in the determination of the appropriate protection measures for coastal sites.

Many definitions of managed realignment exist. The understanding of what the term actually represents in practice has evolved through time and varies regionally, across sectors and among practitioners. A common understanding of managed realignment is further complicated by the use of other related terms; sometimes synonymous with managed realignment while at other times reflecting different concepts. Terms such as managed retreat, setback, regulated tidal exchange, depoldering have all being used in the literature associated with managed realignment, many times inconsistently. The lack of clarity in the use of terminology has contributed to negative connotations expressed by some stakeholders and the general public. This chapter clarifies the terminology currently in use and proposes a wider definition of managed realignment so it can be applicable to encompass the many forms of implementation adopted worldwide. Within this broader context, managed realignment becomes a general term that can be used to describe collectively the many mechanisms implemented to allow coastlines to evolve more flexibly with the objective of promoting more sustainable flood and erosion risk management.

Managed realignment projects are increasingly popular in the western developed countries. The underpinning drivers for the implementation of managed realignment are generally similar and revolve around restoration of natural habitats, improved flood and erosion risk management and climate change adaptation. Emerging national and regional strategies will play an important role in the increase of managed realignment approaches being implemented in the next decades. This chapter provides eight examples of strategies adopted by different countries or regions that are likely to influence the dissemination of managed realignment at present and in the future. Examples are drawn from the UK, Belgium, the Netherlands, Germany, France and the USA. The strategies are discussed in terms of their primary objectives, scope and the preferred mechanisms of implementation.

A key factor in avoiding and minimising the impact of catastrophic dam failure is the ability to draw a reservoir down in the event of an emergency. In the UK there is currently no single accepted approach to determining what represents an acceptable rate of reservoir drawdown. A project is therefore currently being carried out, under the joint Environment Agency/Defra (Department for Environment, Food and Rural Affairs) Flood & Coastal Erosion Risk Management (FCERM) research and development programme, to research and produce guidance on the drawdown capacity required for reservoir safety. This paper summarises some of the research findings from stage 1 of this project and sets out the proposed approach to develop the guidance in the next stage of the project.