In 2002, when colleagues at HR Wallingford, Halcrow and my team (then at the University of Bristol) undertook the first National Flood Risk Assessment (NaFRA) for the Environment Agency (EA), it was a breathtaking exercise. The methodology was hot off the press from the EA’s RASP (Risk Assessment for Strategic Planning) project. The Department of the Environment Food and Rural Affairs (DEFRA) had conducted a National Appraisal of Assets at Risk from Flooding and Coastal Erosion in 2001, but the analysis did not take account of the effect of flood defence systems. The EA had then taken the hugely significant step of developing a National Flood and Coastal Defence Database. On top of this novel dataset, we built a flood defence system reliability calculation that took into account the spatial dependence in water levels. We piloted in the Parrett catchment (somewhere that became infamous for flooding last winter) and then pressed the button on the whole of England and Wales. Less than a year later, we were running climate change scenarios and scenarios of socio-economic change as part of the government’s Foresight Future Flooding Project, and before long Sir David King was taking the results to the US, Russia, India and China.
The race was on for massively broad-scale flood risk analysis. Next stop the world. The Catastrophe (Cat) modellers were making huge steps too, armed with back rooms full of analysts who seldom saw the light of day. One of their team leaders describes the tactic as ‘shock and awe’, a poignant phrase at the time of the 2003 invasion of Iraq. In the Cat modeller’s vernacular, this meant releasing a model of some part of the world nobody at the time thought you could model (China, Vietnam), and then fixing the bugs while everyone else recovered from the shock. It is a trick that seemed to work, with a captive market and nobody allowed to look under the bonnet.
By 2006, the team at the European Joint Research Centre (JRC) at Ispra was using their LISFLOOD broad-scale hydrological and flood inundation model to develop the first European-scale flood risk estimates, driven by ensembles of regional climate model (RCM) scenarios. Even then, the NaFRA and Foresight results for England and Wales were the only national risk estimate available for comparison with the JRC’s results for Europe.