Rising Seas: the Engineering Challenge

In essence, the engineering challenge of designing for rising seas and the associated risk of coastal flooding is rooted in instability.

Sea levels around the world have been relatively stable from a human perspective for about 5,000 years, over which time engineering has emerged and evolved as a distinct foundation of modern civilised society, along with its principles, guiding assumptions and design methodologies. This perception of the shoreline as being in a fixed, ‘stable’ environmental state, in which we have become deeply rooted culturally, psychologically and technically, is in distinct contrast to the largescale variations of sea level that have taken place over geological time. At the last high-water point, some 120,000 years ago, sea level reached more than 6m higher than its present value and on the long timeframe it has varied over a 120m vertical range depending on the degree to which landbased ice has covered the globe.

Recommendations

The consequences of coastal flooding of the built environment, building services and industrial infrastructure are multifaceted and include technical, socio-economic, health and environmental impacts. Homes, places of work and communities are at the centre ;of a cohesive, healthy, functioning civilised ;society, and engineered industrial assets are vital in the modern world to economic wellbeing, energy security, medical and food supply chains, as well as a nation’s key manufacturing industries, building and construction sectors, and agriculture. Adapting these components of modern life to the impacts of sea level rise-induced coastal flooding, is essential for a successful outcome to the influence of climate change in the 21st century and beyond.

In this regard, IMechE recommends that governments around the world:

1. Recognise in coastal flooding policy, strategy and investment decisions the emerging evidence base that indicates the possibility of sea level rises this century significantly greater than previously anticipated and prepare for a minimum of a 1 metre rise in sea level this century but plan for three metres of rise. In this regard, consideration should be given to what measures will be required to address a three metre rise and actions taken to ensure an adaptive-ready built environment and infrastructure.
2. Ensure that policy and strategy include consideration of industrial infrastructure, including but not limited to oil refineries; gas processing plants, chemical processing plants, pharmaceuticals and biopharmaceuticals manufacturing and food processing factories, water and wastewater treatment and processing plants, bulk materials handling facilities, power stations and renewable energy processing sites (biofuels, biogas etc), much of which are located alongside tidal estuaries or on the coastal shoreline.
3. Set up industry task forces to work with the Professional Engineering Institutions to better define adaptive approaches to future fluvial, pluvial and sea level related coastal flooding events, for sea level rises up to 3 metres this century, and the requirements for assessment of the impacts on the building services and industrial infrastructure. In this regard, we strongly suggest that UK Government convenes such a task force to include the UK’s environment agencies, the Health and Safety Executive (HSE), Defra, BEIS, MHCLG and industry expert representatives, to take ownership of the industrial resilience planning for future sea level induced coastal flooding.

Related links

Industrial Flooding: Protecting Critical Infrastructure

With insights from the nuclear, power and water industries join the Industrial Flooding seminar (18 March 2020, London) to hear case studies highlighting the measures being developed by the engineering community to protect critical infrastructure against more frequent and increasingly severe weather events. The seminar will form part of a two-day climate change focused event with a half-day pre-seminar workshop on the new BS EN ISO 14090 standard, taking place on 17 March.