Facing Up to Rising Sea Levels: Retreat? Defend? Attack?

Retreating inland, creating habitable defence structures and building out into the sea are three options proposed to cope with the extremities of rising sea levels, in a futuristic project released today by the Royal Institute of British Architects' (RIBA) think tank Building Futures and the Institution of Civil Engineers (ICE).

The think-piece Facing up to Rising Sea Levels: Retreat, Defend, Attack? warns that the future of our coastal cities is in jeopardy due to rising sea levels, sinking landmasses and an increase in storm frequency. With over 12,000 km of coastline, radical thinking is urgently needed to protect the UK's at-risk communities from extreme flooding.





Focusing on Kingston upon Hull and Portsmouth, two of the UK's highest flood risk areas, the research presents six scenarios set up to 90 years in the future, proposing different solutions based around three realistic briefings:

Retreat (or managed realignment): rising sea levels have reduced landmass. Hard engineering defences are no longer sustainable or affordable. Moving the line of defence inland, allowing flood water to occupy previously protected city areas is the only option.

Defend: there is a growing deficit on flood defences which public funding is not covering, but the benefits of preventing water entering the existing cities still outweigh the costs. Flood defence systems must be made commercially viable to attract private investment.

Attack: the population of the UK has increased significantly, meaning building out into the water, via stilted and floating structures, is an attractive option to alleviate pressure inland. This has been proven successful overseas and due to high demand for space the public and private sector are both willing to invest in expanding seaward.



"The scenarios we have created are extreme, but it is an extreme threat we are facing," said Ruth Reed, RIBA President. "Approximately 10 million people live in flood risk areas in England and Wales, with 2.6m properties directly at risk of flooding from rivers or the sea. However, if we act now, we can adapt in such a way that will prevent mass disruption and allow coastal communities to continue to prosper. But the key word is 'now'."

The report urges Government, built environment professionals, planning authorities and the public to focus on tackling the man-made obstacles that currently prevent such solutions being made a reality.





"A proactive and united, almost war-like approach is needed if we are to win the battle against what is set to be our biggest challenge in the next century, the 'water invasion'," said Ben Hamer, Chair of the ICE steering group.

"Some very difficult decisions need to be made in the near future, and to do this we need integrated thinking. The UK must urgently change the way it plans, builds and designs at-risk communities.

This requires a strategic vision at local and national level, more co-ordination and improved communication between stakeholders, and some very creative thinking about how solutions can be developed to be financially sustainable."

The scenarios were master-minded by a group of top architects, civil engineers, city designers, planners, developers, policy-makers, ecologists and futurologists.

The full project, including sketches and details of the proposed "new cities," will be exhibited at the Building Centre, London 6th Jan - 29th Jan 2010, before travelling to Portsmouth 15 - 27 February, and Kingston-upon-Hull 15 - 28 April 2010.

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