El Niño: Impact and Responses in the Road Sector of Latin America and the Caribbean

The climate phenomenon of El Niño is a natural event characterized by an unusual warming of the Pacific Ocean, and traditionally has been a source of significant impacts on Latin America and the Caribbean. This phenomenon impacts directly and indirectly various sectors, with the transportation sector being hit the hardest, particularly the road infrastructure. In general terms, an estimated 25% to 50% of losses from natural disasters are on the transportation sector, i.e. 1 out of every 4 dollars lost due to natural disasters is being taken by this sector.

To grasp its true impact, we must analyze the climate-related consequences and the phenomenon's implications for the region's roads. The El Niño phenomenon describes an increase in ocean surface temperatures, altering the weather. In Latin America and the Caribbean, this often translates into unusual rainfall: while some areas experience extreme droughts, others face extremely heavy rains.

The effects of these weather disturbances on roads are evident: deterioration of infrastructure due to heavy rains that accelerate pavement degradation, slope erosion, gutter failure and bridge collapse; landslides in mountainous areas that often cause road blockages; and floods in prone areas, causing waterlogging of roads, disrupting traffic and damaging the underlying infrastructure.

There are also indirect consequences mainly related to the economic costs derived from the loss of income and road repairs; access to basic public services such as schools and hospitals; as well as an increased risk of car accidents.

In 1997, El Niño had an estimated USD 1.7 billion impact on transportation in Latin America. In Colombia, during the 2010–2011 winter wave, more than 31,635 kilometers of roads were damaged, affecting 3.2 million people and 568,000 homes. The total economic impact of the damages caused by El Niño was in the excess of USD 6.8 billion, of which USD 1.8 billion was on the transportation sector.

In Paraguay, the 2015–2016 El Niño brought heavier-than-usual rains that tore down 40 bridges and required repairs on more than 11,000 kilometers of local roads; damages and losses exceeded USD 220 million and reconstruction needs surpassed USD 150 million.

Adaptation and solutions

In understanding the impact of El Niño on the countries in the region, it becomes clear that it is not just about addressing road emergencies, but rather promoting the development of comprehensive technical designs to achieve long-term optimal road service that ensures their useful life, withstanding external impacts. In other words, it is essential to promote resilient infrastructure capable of withstanding these regular weather events.

The Guide to Good Practices for Road Adaptation to Climate (caf.com) by CAF—development bank of Latin America and the Caribbean—, puts forward solutions that could help reduce the impact of this phenomenon on the different phases of road projects:

1. Designing improved drainage systems.
2. Using resilient construction materials.
3. Implementing advanced monitoring systems.
4. Promoting education and training.

The identified actions could be classified into three areas: i) physical measures, e.g. reconstruction of drainage systems considering variability forecasts and climate change; ii) organizational measures, such as the installation of weather stations for data collection and analysis; or iii) institutional measures, e.g. the creation of a dedicated unit in the Ministry of Public Works or Transportation to manage road network climate change adaptation programs. Designing these actions requires strategic and adaptive planning.

Facing the El Niño phenomenon requires strategic and adaptive planning, focused on developing resilient infrastructure that helps curb the impact on the road sector in Latin America and the Caribbean, ensuring safety and efficiency on the region's roads. In this sense, work is needed in four priority areas:

• Risk and climate vulnerability assessment in road projects;
• Tools and resources during project planning and evaluation, which allow for the inclusion of adaptation measures from the outset;
• Recommendations for the design and construction of climate-resilient roads;
• Strategies for road management and maintenance in the context of climate change.