Building Futures has undertaken a number studies into the challenges our society faces as a result of more frequent and serious flooding, 2007’s publication Living with Water: Visions of a Flooded Future the 2008 debate, This House Believes the Thames Gateway Area is Sunk and the team has supported and advised on the RIBA’s Climate Change Toolkit Document Designing for Flood Risk.
Looking to a 100 year horizon of climate change predictions, we will address how the urban, built environment needs to react now. Conservative estimates predict sea-levels to continue ro rise as the oceans warm and the ice caps melt. Coupled with isostatic rebound (the South sinking relative to the North) the affects grow ever more dramatic for large centers of population on the coast. Predicted weather patterns show increased rainfall intesity, leading to sever problems of surface water flooding in built up areas.
The need to develop strategies for tackling this inescapable phenomenon is pressing. Given three broad solutions – RETREAT, DEFEND, ATTACK – we need to determine which approaches are suitable in which contexts. RIBA Building Futures and the Institution of Civil Engineers will explore the future decision-making processes on coastal management strategies.
Changing sea levels is not a new phenomenon. In the Netherlands, for example, with 40% of its surface under sea level, water management and water defense have been practiced since time immemorial. The Dutch created mounds and dykes, windmills, canals with locks and sluices, the Delta Works and the Afsluitdijk, all to keep the water out. Now there is a growing realisation that living with water is a viable and sustainable solution: letting it in! So water management changed with a movement towards floating cities, seawater inlets, freshwater basins combined with nature reserves.
A STORY IN THREE PARTS
To retreat is to step back from the problem and avoid a potentially catastrophic blow. It is to move critical infrastructure and housing to safer ground and to allow the water into the city to alleviate flood risk. This is critically different from abandonment, as we propose a long-term planned and managed process.
To defend is to ensure the sea water does not enter the existing built environment. This will require built defences to ensure the standard of protection will be met in the distant future as sea-levels rise. Although it is currently an expensive policy to adopt, can the defences themselves be designed in a way to make them economically and commercially viable?
To attack is to advance and step seaward of the existing coastline. There is massive development potential to be gained for coastal cities by building out onto the water. This further reduces the need to sprawl into the countryside and ensures their sustained social and economic vitality. Although it leaves parts of the city still vulnerable to flooding, can the long term benefit of new development outweigh this risk?
In July 2009, Building Futures and the Institution of Civil Engineers hosted a design charrette, bringing together a number of professionals from various relevant sectors. We had a select group of top architects, civil engineers, city designers, planners, developers, policy-makers, ecologists and futurologists. The brief was to produce both architectural and infrastructural responses to rising sea-levels on two case study cities; addressing the issue with our three proposed future scenarios – Retreat? Defend? Attack?
For more information on this project contact us at BuildingFutures@riba.org
Facing Up To Rising Sea Levels Travelling Exhibition
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