Enhancing the Climate Resilience of Africa’s Infrastructure: The Roads and Bridges Sector

Africa’s development is highly dependent on an adequate, reliable road system. But climate change is expected to take a heavy toll on the region’s transport infrastructure, especially roads and bridges. To address this challenge, a new World Bank study helps planners determine the most cost-effective and appropriate adaptation pathway under a variety of climate scenarios.

Africa’s future depends on its roads

  • An adequate and reliable road network will be key to Africa’s economic and social development. Good-quality road connections can greatly expand access to jobs, markets, schools, and hospitals. For rural communities, in particular, a road is often an essential lifeline that links isolated villages to economic opportunities and services.
  • The low density and poor condition of the existing road infrastructure are a serious impediment to the region’s growth. Currently, only 1/3 of rural inhabitants live within two kilometers of an all-season road–the lowest accessibility in the developing world. Moreover, insufficient funding of routine maintenance accelerates the deterioration of the network, leaving many roads in poor condition.
  • As part of a broader effort to expand and upgrade its transport network, Africa will see substantial investment in road infrastructure over the next decades. When combining both regional initiatives and country-level masterplans, capital investment in the road sector will average about $4.6 billion a year, for a total of $78 billion through 2030.

Climate change will take a heavy toll on the African road system

  • To ensure road spending delivers the best possible return and brings lasting development benefits, it is critical that investment plans take into account the consequences of a changing climate, as road assets are particularly vulnerable to climate stressors such as higher temperatures, increased precipitation, or flooding.
  • Virtually all models show that weather extremes will indeed put considerable pressure on Africa’s road system. The damage and accelerated aging of roads caused by climate change will require increased maintenance and more frequent rehabilitation.
  • Aside from higher maintenance and rehabilitation costs, climate-related damage to the road infrastructure will also cause more frequent disruptions to the movement of people and goods, with direct consequences on economic productivity.

Fortunately, there are effective ways of adapting new roads and modifying existing ones to enhance climate resilience.

Arne Hoel/World Bank

Measuring the cost of inaction vs. proactive adaptation

To help planners determine the most cost-effective and appropriate adaptation pathway, the study has developed a methodology to compare the cost of inaction vs. proactive adaptation, looking at three main dimensions:

  • Assessing the cost of road assets over their entire life cycle, including construction, maintenance, repairs, and rehabilitation: this analysis is important as climate-resilient roads tend to have higher upfront construction costs, yet, in many cases, those are more than offset by the lower annual cost for maintenance, repairs, and rehabilitation.
  • Considering a variety of climate change scenarios: most projections indicate that Africa’s climate will be very different from what it is today; however, there is no consensus as to the nature, intensity, and geographic distribution of those changes. That’s why the methodology used in this study was designed to take into consideration multiple climate scenarios. Integrating a full range of possible climate futures may complicate the analysis, but failure to do so could cause planners to “miss the mark” and over-/under-invest in climate resilience.
  • Quantifying the broader impact of climate-related traffic disruptions: when climate events shut down or reduce the capacity of a road, the consequences on supply chains, economic output, and access to services will vary widely based on local factors such as the volume of traffic on a particular road or the existence of alternative routes. On high-traffic roads, even relatively mild changes in climate could severely affect people and the economy—making the case for adaptation particularly strong.

No “one-size-fits-all” solutions

Based on this methodology, the study finds that:

  • Adequate road maintenance is the most critical and most efficient way of reducing the impact of a changing climate on the road system. In the absence of an adequate maintenance regime, the damage caused by climactic events is exacerbated. 
  • Investing proactively in pavement improvements to account for higher temperatures is almost always justified, especially considering that the incremental cost of such adaptation measures is relatively low.
  • When it comes to precipitation and flooding, the case for adaptation is more nuanced: enhancing resilience to these stressors generally comes with a hefty price tag, and subsequent savings on maintenance and rehabilitation may not be enough to compensate for higher upfront costs. In that context, factoring in the broader impact of road disruptions is essential to determine whether or not adaptation makes good economic sense.
  • When deciding whether and how to adapt roads to the climate challenge, transportation planners should evaluate their options on a case-by-case basis and avoid “blanket prescriptions”.

To put these recommendations into practice and protect its transport infrastructure against the effects of climate change, the region will need to boost the financial, technical, and institutional capacity of the road sector. To that end, the World Bank has developed several initiatives to help countries incorporate climate change into road asset management. The Bank is also working with the Africa Union Commission and the United Nations Economic Commission for Africa (UNECA) to set up the new Africa Climate Resilient Investment Facility (AFRI-RES), which will develop the region’s capacity to integrate climate change considerations into the planning and design of long-lived investments.

This study has been developed with financial support from the UK Department for International Development (DfID), the Nordic Development Fund (NDF), the Kredit Anstalt für Entwicklung (KfW), the Agence française de développement (AFD); the Bank-Netherlands Partnership Program (BNPP); and the Trust Fund for Environmentally and Socially Sustainable Development (TFESSD).