British Engineers Use “9 Box Matrix” As Flood Design Guide

Today the British Institute of Mechanical Engineers, “IMechE”, issued guidelines for their 130,000 members to use when engineering for rising sea level. I am delighted that it is based upon a tool that I created a few years ago, the “9 Box Matrix.” The announcement was done at a press conference at their HQ in London, which I attended.

The report RISING SEAS: THE ENGINEERING CHALLENGE can be downloaded from their website: www.imeche.com

As shown below, the 9 Box Matrix is a simple construct with three rows for different risk levels and three columns for different time horizons. As a standard, I use 30, 50, and 100 years, though that can be varied for specific users who might need shorter or longer time frames.

IMechE Report:  ‘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 time frame 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.’  Click here to download the report