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NETWORK / 19 / APRIL 2019 of natural hazards in a consistent way. That's why Mott MacDonald, EDF Energy and The Met Office worked together to provide a set of technical volumes and case studies for the Energy Technolo- gies Institute (ETI) to fill this gap, titled 'Enabling Resilient UK Energy Infrastructure: Natural Hazard Characterisation'. Engi- neers will use this when consider- ing how to protect infrastructure against a variety of hazards. A‚er all, recent weather dis- asters have shown the damaging effect they can have on infrastruc- ture. In 2011, an earthquake of magnitude 9.0 centred 130km off the east coast of Japan triggered a 15m tsunami which struck the Fukushima nuclear plant. This disabled the plant's power supply and cooling systems of three of the nuclear reactors, leading to a nuclear disaster. The reactors were robust when initially hit by the earthquake but vulnerable to the tsunami that was triggered. The tsunami led to 19,000 deaths and caused significant damage to coastal ports and towns with over a million buildings destroyed in its path. This disaster highlighted not only the impact that individual hazards can have on infrastruc - ture but also how the combina- tion of various natural hazards can lead to more severe impacts than if hazards had occurred separately. The Fukushima disaster led to a worldwide safety review of nuclear stations with new protection systems, safety equipment and protocols instituted to prevent such severe consequences in the future. The impact of storms In the UK, some of the most damaging natural hazard events in recent times have been caused by storms. A sequence of storms struck the UK in December 2013 leading to severe storms in multiple areas. Several hundred homes on the east coast of England required evacuation, while the Thames Barrier was closed to protect London from the effects of this event. Extreme wind speeds across Scotland forced the clo - sure of the rail network and le‚ approximately 100,000 homes without power. It is no surprise that flooding is the second most serious natural hazard risk for the UK following the potential for a flu epidemic, with over five million properties at risk in England alone. As well as affecting properties, flooding can damage national critical infrastructure such as electric - ity power supply, leading to a cascade failure in other sectors. Therefore, understanding the flood risk now and in the future, and building infrastructure with resilience to flooding, is critical to the sustainability of the UK and for society's ability to continue going about daily life without disruption, economic damage and environmental cost. The risks associated with CASE STUDY: Cottam Power Station The Cottam power station, owned by EDF Energy, is situated in Nottingham and extends over 620 acres of mainly arable land. The station was commissioned in 1969 by the Central Electricity Generating Board. The surrounding land and floodplain is protected by Environment Agency (EA) flood defences along with the River Trent. The power station site is located in Flood Zone 3a – a high likelihood flooding area. To better characterise the river flooding hazard, it is important to consider a wide range of factors that could contribute to the risks. These can be split into three broad categories: site characteristics, different sources of flood risk, and wider factors that may affect flood risk, such as climate change and interdependencies. Climate change allowances for flows and sea level should be considered when assessing future flood risk to Cottam. By 2115, there's expected to be an increase in fluvial flow by 20, 30 and 50 per cent respectively for Central, Higher Central and Upper End allowance category. There is also expected to be an increase in sea level of 1.21m compared to the baseline year 1990. The joint probability of a fluvial event and a tidal event should also be considered when assessing the flood risk for Cottam power station. Apart from considering the resilience to flooding for an individual asset, it is crucial to understand the interdependencies between different assets to ensure the system is resilient. As ever, it is important to consider the flood risk during the design life of the infrastructure and beyond to its decommissioning stage when deciding the level of river flooding to protect against. To determine design conditions for any new development work and obtain planning permission, a site-specific Flood Risk Assessment study must be carried out. It is also necessary to meet the requirements of the National Planning Policy Framework and local planning policy. Local plans should apply a sequential, risk-based approach to the location of development where possible to avoid flood risk to people and property and effectively manage any residual risk. An example of coastal erosion.