Flood risk management

Flooding is now the most common natural disaster across the world, accounting for 40 percent of all the threats nature currently presents. Rapid urbanisation, combined with the increasingly devastating impacts of climate change and severe weather events are just some of the contributing factors which mean flood management is more important than ever.

At Arup, we provide integrated, holistic and truly sustainable solutions to help developers, local authorities, government agencies and infrastructure operators to understand and manage flood risk. We’ve drafted national guidance for CIRIA, worked closely with the UK Environment Agency for many years and supported flood management authorities such as the Regional Water Management Boards in Poland.

An integrated approach

Successfully managing the risks that floods present requires an integrated approach. This should include the development of new technologies, learning from past and current industry knowledge and the effective integration of disciplines. All the while it’s crucial to listen to stakeholders and really understand the needs of local inhabitants.

It’s also critical that we analyse the trends and challenges within flooding that may lie ahead, and aim to have water management at the heart of all building and built environment design. Our Drivers of Change Water 2.0 publication provides a focus on the systems of water harvesting, packaging, and distribution, as well as the social and political priorities of water consumption. All of these elements need to be integrated into future flood management and design between now and 2050.

Enhancing the built and natural environment

While managing the risks of flooding is our main priority, we also look to enhance both the built and natural environment for people and wildlife. For example, our work with the Connswater Community Greenway and East Belfast Flood Alleviation Scheme in Northern Ireland will reduce flooding risk for 1,700 homes and businesses, while increasing the biodiversity and natural aesthetics of the waterway. In Poland, we have been able to make best use of the natural environment, including the improvement of natural retention in the upstream sections of the Nida and Czarna Staszowska rivers.

We also understand how critical it is to integrate water sensitive design into our built environments. Our technical support services for the Leeds Flood Alleviation Scheme not only aim to improve wildlife along the corridor of the River Aire but will ensure the further growth and regeneration of the Leeds economy in Northern England. This will be done by protecting transportation infrastructure, homes and existing businesses against flooding, whilst still ensuring aesthetically pleasing views that the river provides by being so close to the city.

Building for resilience

Even with the best defences, it is impossible to stop every single flood. Population migration and sea level rise mean that coastal cities face a range of increasingly severe challenges in the future, and many cities will not be able to rely solely on engineering structures for flood protection. They will need to develop a suite of policy responses to increase their resilience in the face of uncertain and rapidly developing flood risk.

This is why we provide a strong focus on helping communities, large and small, develop resilience to flooding. This includes emergency planning and response and building in resilience to existing infrastructure. For example, in Ireland, we are working with Kilkenny County Council to ensure the local community is more resilient and better prepared, through early flood warning systems and flood management measures for individual properties, such as demountable flood door barriers and non-return valves.

Our evidence-based City Resilience Index highlights what determines whether cities can cope with shocks such as flooding. We have also developed flood hazard Assessment and Adaption Toolkits across the world, including flash flooding risk of natural drainage catchments and rivers across the territory of Hong Kong, as well as relieving flood risk in the low-lying urban area. In New York, we have researched ways to make homes more resilient to storm damage and sea level rise, following damage by Hurricane Sandy in 2012, while informing flood mitigation for the city’s transit system.

Together, we can help anticipate and adapt to the extremes of flooding, to ensure communities and infrastructure are safe and resilient, both today and in the future.