Roads are essential to society and constructing climate resilient highways holds the key to unlocking solutions to the tough challenges ahead.
Constructing climate resilient highways holds the key to unlocking solutions to the tough challenges ahead.
Roads are essential to society - allowing people to access education, healthcare, and other key services, whilst reducing social isolation by connecting communities and supporting social and cultural activities.
Roads also support economic development - connecting people and businesses to markets, suppliers, and customers as well as leading to increased economic activity and job opportunities.
Given the importance of roads to how society functions, attention has focused on how designing and constructing climate resilient roads holds the key to unlocking solutions to the challenges ahead.
Five experts, reflecting on a recent IRF policy dialogue give their perspectives on how we can support climate resilient transport infrastructure in an increasingly complex world.
Given the importance of roads to how society functions, attention has focused on how designing and constructing climate resilient roads holds the key to unlocking solutions to the challenges ahead.
The Ethiopian Roads Administration is responsible for an extensive road system across a vast geographic area, involving a range of climatic conditions - over 28,600km of roads and 5,600 bridges. This poses significant challenges in terms of how we manage our technical, human, and financial resources.
Ethiopia is one of the most vulnerable countries to climate change – more extreme weather events, changes to seasonal rainfall and increased temperatures. Our investment decisions are complex - requiring careful consideration to ensure that our resources are used effectively. In making informed decisions, we require support to access evidence on what works and why, as we adapt our road infrastructure to future climates.
We can learn much from what partners have done in other contexts, but any decisions must reflect local conditions, whilst acknowledging and developing existing equipment and capacities. Evidence on best practice in climate resilient pavement surfacing must help us advocate for change in our organisation, Government and internationally around the need to make upfront infrastructure investments to deliver financial dividends and climate resilience.
Rapid demographic changes often lead to the upgrading of transport infrastructure. Every country must better understand how roads built today can be future-proofed. Evidence is essential to support key choices delivering future dividends – helping to decide what mechanisms need to be in place.
Powerful software tools, such as Highway Development Model 4, can help assess road condition, estimate cost of maintenance, and evaluate economic and social benefits of road investments. These tools must be used correctly - requiring a steady pipeline of adequately trained staff and development of in-country capacity to ensure the best use of these systems.
Road authorities and administrations must learn lessons from international experience and experiment in country to uncover the most appropriate approaches that work with existing capacities.
The realities of climate change highlight that business as usual approaches are no longer acceptable. Adverse weather conditions will increase in frequency and those managing road infrastructure must reflect on what evidence they need to make informed decisions about how road pavement surfacings are designed and constructed.
Experimentation and innovation in approaches to road pavement design are an integral element of developing climate resilient roads, but ensuring uptake of new approaches requires us to engage pro-actively with decision makers and advocate for change.
Framing policies must be attuned to local realities and ways of working. Using approaches developed in one setting must be tested and refined in others - this may involve acquisition of new skills or equipment. We must develop a systems approach to the issue and understand how interventions in one area can support or undermine those in others.
Research by the University of Birmingham and our partners aims to demonstrate the technical and economic suitability of three global best-practice road surfacing technologies that could help to prepare for climate change impacts in Low-income Countries.
Modified Epoxy Chip Seals (MECS), Modified Epoxy Asphalt Surfaces (MEAS) and Fibre Mastic Asphalt (FMA) are the result of many years of research in New Zealand (MECS and MEAS) and Malaysia (FMA) with in-situ performance demonstrated through trials and, as a result, they are routinely used in service.
These surfaces are more resilient to climate impacts - particularly relevant in countries experiencing temperature increases. Bitumen oxidizes quickly, becomes brittle, and cracks in hotter temperatures, whilst epoxy lasts longer. Combining or using alternative materials also means less bitumen is needed over the road’s life - capitalising on savings in carbon emissions from the construction process and using the material.
These surfaces, whilst initially more expensive, can last four to six times longer than traditional surface methods and require less maintenance than existing surfacings. As such, it is important to develop a long-term strategy that acknowledges the higher up-front costs to deliver longer-term benefits.
By investing in resilient roads, communities can ensure that their transportation infrastructure is sustainable, efficient, and able to withstand the challenges of the future. As populations grow and people move out of poverty, these road surface improvements should also help the roads be more resilient to increasing and diversified demand.
Research Fellow
William joined GSDRC at the University of Birmingham in 2015 from the Overseas Development Institute.
