Flood resilience for UK infrastructure

Initiated by CIRIA, and building upon previous collaborative research projects on property-level flood resilience, this exceptional initiative aims to address some of the critical infrastructure issues raised by recent severe flooding in the UK. The Environment Agency’s analysis of the cost of the 2007 floods underlines the importance of continued investment in managing flood risk. The final report, which is the key output from the project, provides an overview of how the flood risk posed to critical infrastructure systems is currently managed across the UK.
    
The project team of CIRIA and Arup engaged in an extensive consultation phase, involving a workshop and an online survey completed by some of the UK’s leading infrastructure asset owners and operators. The findings of this consultation were incorporated in an extensive review of both national and international practice that formulated the final project report.
    
Robert Runcie, Environment Agency Director of Flood and Coastal Risk Management, said: “This report shows that operators must be fully prepared to reduce the risk of flooding to their critical infrastructure systems, particularly in light of future climate change. Operators must also continue to invest in business continuity measures for their systems so that essential services can continue even during a flood.
    
“The Environment Agency has launched a new dedicated flood warning service aimed specifically at infrastructure operators, which issues tailored warnings for specific sites, allowing organisations to take action earlier to protect crucial assets. We urge operators to sign up by contacting Frazer Rhodes on 08708 506 506.”
    
The report provides an overview of the regulatory framework and outlines the key challenges currently facing the industry in this area. A brief introduction is given on the principles of flood risk management and places flood resilience and resistance in a wider context. Also, published case-studies provide lessons learned by infrastructure owners and operators who have suffered flooding problems in the past.
    
The report goes on to give key conclusions and recommendations for both industry and regulators to further enhance the flood resilience and resistance of the UK’s critical infrastructure.

The report
CIRIA project RP913 ‘Flood Resilience and resistance for critical infrastructure’ builds on previous CIRIA-managed collaborative research on property-level flood resilience (CLG, 2007) and with the aim of addressing some of the critical infrastructure (CI) issues raised by recent severe flooding in the UK. This publication, which is the main output from the project, provides an overview of how the risk posed to CI systems by flooding is now managed across the UK.
    
CI comprises: “those facilities, systems, sites and networks necessary for the functioning of the country and the delivery of the essential services upon which the daily life in the UK depends”. Flood resilience involves designing an infrastructure asses, or adapting an existing infrastructure asset so that floodwater is excluded during flood events and normal operation can continue with no disruption occurring to the essential services the asset provides. These two techniques have a central role to play in managing the flood risk associated with CI systems.
    
The publication provides an overview of the regulatory framework and outlines the main issue now faced by the industry in this area. A brief introduction is given to the principles of flood risk management to place flood resilience and resistance into a wider context. A range of case studies is provided that describes the lessons identified by infrastructure owners and operators who have suffered flooding problems in the past. Flood risk management for CI across the UK is then considered with respect to:

• flood risk assessment
• adopting resilience and resistance measures
• investment prioritisation.

Recommendations
The conclusions and recommendations to this publication are summariesd as follows:
The majority of flood risk assessment work undertaken to date by CI operators has made use of national flood maps prepared by the Environment Agency (EA), Scottish Environment Protection Agency (SEPA) and Northern Ireland Rivers Agency (NIRA). These maps provide information on a limited number of annual probabilities of events for river and coastal flooding only, ignoring the presence of flood defences. These maps do not factor in an allowance for climate change (except in Northern Ireland). Now it is challenging for operators to assess the degree of exposure to surface, groundwater and infrastructure-failure flood hazard registers, need to address this issue, making better use of existing information and ensuring that new data is collated in consistent format.
    
The main issue with adopting resilience and resistance measures is which standard to use. Sir Michael Pitt recommended that resistance to a 0.5 per cent (1 in 200) annual probability flood would be a proportionate starting point for critical infrastructure. It is easier to protect existing infrastructure from flooding that it is to adapt and upgrade existing legacy infrastructure. The 0.5 per cent annual probability standard will be particularly challenging to achieve for roads and legacy rail infrastructure. It is recommended that guidance on appropriate resilience/resistance standards is developed for different categories of CI, which recognises the existing variations in both flood hazard exposure and resilience/resistance levels. This publication suggests a possible risk-based framework for these standards.
    
Flood resilience measures should be adopted as an integral part of individual organisations’ business continuity management processes, whole-life asset management plans and climate change adaptation strategies. CI owners need to develop long-term strategic investment approaches that allow for optimised investment decision making. The economic regulators should aim to provide a framework to achieve this objective.
    
John Dora, Network Rail and Project Steering Group Chair, said: “The project steering group was a diverse and experienced group who had a whole raft of challenges to overcome. The team from CIRIA and Arup have done a really superb jog in logging/collating and sifting data and information received. Our funding partners and stakeholders – from government to service providers and their involvement has, to my mind, allowed us to produce a report that carries – and will carry – a great deal of weight and influence that will probably be around for decades. It’s been an honour to chair the steering group.”
    
Building upon the findings of the project, CIRIA are currently preparing a proposal to develop a good practice toolkit to help infrastructure asset managers implement flood resilience for their assets.