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disaster recovery

Resilient transport investments: a climate imperative for Small Island Developing Countries

Franz Drees-Gross's picture


Transport in its many forms – from tuk-tuks in Thailand to futuristic self-driving electric cars – is ubiquitous in the lives of everyone on the planet. For that reason, it is often taken for granted – unless we are caught in congestion, or more dramatically, if the water truck fails to arrive at a drought-stricken community in Africa.

It is easy to forget that transport is a crucial part of the global economy. Overall, countries invest between $1.4 to $2.1 trillion per year in transport infrastructure to meet the world’s demand for mobility and connectivity. Efficient transport systems move goods and services, connect people to economic opportunities, and enable access to essential services like healthcare and education. Transport is a fundamental enabler to achieving almost all the Sustainable Development Goals (SDGs), and is crucial to meet the objectives under the Paris agreement of limiting global warming to less than 2°C by 2100, and make best efforts to limit warming to 1.5°C.

But all of this depends on well-functioning transport systems. With the effects of climate change, in many countries this assumption is becoming less of a given. The impact of extreme natural events on transport—itself a major contributor to greenhouse gas emissions—often serve as an abrupt reminder of how central it is, both for urgent response needs such as evacuating people and getting emergency services where they are needed, but also for longer term economic recovery, often impaired by destroyed infrastructure and lost livelihoods. A country that loses its transport infrastructure cannot respond effectively to climate change impacts.

How to protect metro systems against natural hazards? Countries look to Japan for answers

Sofía Guerrero Gámez's picture
Photo: Evan Blaser/Flickr
The concentration of population in cities and their exposure to seismic hazards constitute one of the greatest disaster risks facing Peru and Ecuador. In 2007, a magnitude 8.0 earthquake along the southern coast of Peru claimed the lives of 520 people and destroyed countless buildings. The most recent earthquake in Ecuador, in 2016, left more than 200 dead and many others injured.
 
Of course, these risks are not exclusive to Latin America. Considered one of the most earthquake-prone countries in the world, Japan has developed unparalleled experience in seismic resilience. The transport sector has been an integral part of the way the country manages earthquake risk— which makes perfect sense when you consider the potential consequences of a seismic event on transport infrastructure, operations, and passenger safety.

Resilience in urban transport: what have we learned from Super Storm Sandy and the New York City Subway?

Ramiro Alberto Ríos's picture
Photo: Stefan Georgi/Flickr
Back in 2012, a storm surge triggered by Super Storm Sandy caused extensive damage across the New York City (NYC)-New Jersey (NJ) Metropolitan Area, and wreaked havoc on the city’s urban rail system.

As reported by the Metropolitan Transportation Authority (MTA), the subway suffered at least $5 billion worth of damage to stations, tunnels and electrical/signaling systems. The Port Authority Trans-Hudson network (PATH) connecting NYC to NJ was also severely affected, with losses valued at approximately $871 million, including 85 rail cars damaged.

In the face of adversity, various public institutions in charge of urban rail operations are leading the way to repair damaged infrastructure (“fix”), protect assets from future similar disasters (“fortify”), restore services to millions of commuters and rethink the standards for future investments.

NYC and NJ believe that disasters will only become more frequent and intense. Their experience provides some valuable lessons for cities around the world on how to respond to disasters and prepare urban rail systems to cope with a changing climate.

What El Niño has taught us about infrastructure resilience

Irene Portabales González's picture
Also available in: Español
Photo: Ministerio de Defensa del Perú/Flickr
The rains in northern Peru have been 10 times stronger than usual this year, leading to floods, landslides and a declaration of a state of emergency in 10 regions in the country. Together with the human and economic toll, these downpours have inflicted tremendous damage to transport infrastructure with added and serious consequences on people’s lives.

These heavy rains are blamed on El Niño, a natural phenomenon characterized by an unusual warming of the sea surface temperature in the central and eastern equatorial Pacific Ocean. This phenomenon occurs every two to seven years, and lasts about 18 months at a time. El Niño significantly disrupts precipitation and wind patterns, giving rise to extreme weather events around the planet.

In Peru, this translates into rising temperatures along the north coast and intense rainfall, typically shortly before Christmas. That’s also when “huaicos” appear. “Huaico,” a word that comes from the Quechua language (wayq’u), refers to the enormous masses of mud and rocks carried by torrential rains from the Andes into rivers, causing them to overflow. These mudslides result from a combination of several natural factors including heavy rains, steep slopes, scarce vegetation, to name a few. But human factors also come into play and exacerbate their impact. That includes, in particular, the construction of human settlements in flood-prone basins or the absence of a comprehensive approach to disaster risk management.

This year’s floods are said to be comparable to those caused by El Niño in 1997-1998, one of the largest natural disasters in recent history, which claimed the lives of 374 people and caused US$1.2 billion worth of damages (data provided by the Peruvian National Institute of Civil Defense).

The “plastic bridge”: a low-cost, high-impact solution to address climate risk

Oliver Whalley's picture
Also available in: Français
Photo: Anthony Doudt/Flickr
Bridges are critical links in the transport network. In their position across waterways, they are exposed to the full effects of flooding and landslides, and are often the first pieces of infrastructure to be damaged in the event of a disaster. They also typically take weeks or months to repair.  Besides causing expensive damage to the infrastructure itself, disruptions in connectivity also have a much broader impact on economic productivity and people’s ability to access essential services. As many places are expected to witness more intense and frequent rainfall as a result of climate change, the risk to bridges will only worsen: more rainfall will lead to bigger river flows and more damage to bridges, especially those designed to handle smaller storms.

At each end of a bridges is a structure which supports the weight of the deck. These are known as abutments, and they are often the first part of the bridge to fail. Blockage of the main channel by debris can cause water to look for the path of least resistance around the sides of the bridges, thus placing the abutments at risk.

Traditional bridge construction requires the installation of piles for the foundations of abutments—a lengthy and expensive process that involves specialist materials, skills and equipment.

But there is another promising solution: Geosynthetic Reinforced Soil (GRS) abutments. These allow for rapid and resilient construction of bridge abutments using locally available materials, without specialized equipment. With GRS, bridges can be constructed in as little as five days (Von Handorf, 2013) and at a cost 30-50% lower than traditional approaches (Tonkin and Taylor, 2016) .

GRS abutments are based on ‘geogrids,’ a high density mesh made out of polyethylene (plastic). Layers of soil and geogrid are combined to create a solid foundation for the bridge deck. Construction can be completed with basic earthmoving and compaction equipment, and a range of local fill materials can be used with guidance from geotechnical specialists.