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disaster risk management

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

Oliver Whalley's picture
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.

Turning Trash Talk into Action: A Story of Ibadan, Nigeria

Salim Rouhana's picture
Solid waste presents a significant challenge to Ibadan's capacity to manage its high exposure to flooding and further contributes to outbreaks of infectious diseases by human contact with improperly disposed and untreated waste. Photo credit: Farouk Banna

In a rapidly urbanizing world, our incautious thirst for plastics and non-degradable products continues to adversely affect local environments and air quality, and contributes to climate change. The need to rethink how to collect and dispose of solid waste is urgent. Whilst many countries and cities have put forth encouraging efforts to recycle and reduce waste, the levels of consumption and the production of waste continue to increase.

A new partnership to enhance the climate resilience of transport infrastructure

Shomik Mehndiratta's picture
Photo: Norsez Oh/Flickr
Since 2002, more than 260,000 kilometers of road were constructed or rehabilitated by World Bank supported projects. For these investments, and future Bank transport investments to really realize their intended impact supporting the Bank to achieve its twin goals, we believe it is critical that they are resilient to climate and possible climate change.
 
Already transport damages and losses often make up a significant proportion of the economic impacts of disasters, frequently surpassing destruction to housing and agriculture in value terms. For example, a fiscal disaster risk assessment in Sri Lanka highlighted that over 1/3 of all damages and losses over the past 15 years were to the transport network. Damage is sustained not only by road surfaces or structures, but also by bridges, culverts, and other drainage works, while losses occur when breaks in transport links lead to reduced economic activity.
 
Along with additional stress from swelling urban populations worldwide, rising sea levels, changes in temperatures and rain patterns, and increasing severity and frequency of floods and storm events are the key climate change factors that make conditions more volatile. Ultimately it is these scenarios and their potential outcomes that threaten the longevity and functionality of much existing transport infrastructure. Indeed, damage to transport infrastructure and consequent disruption to communities from climactic events is a growing threat.
 
Compounding the challenge of addressing these conditions is the difficulty that exists in precisely forecasting the magnitude, and in some cases the direction, of changing climactic parameters for any particular location. Meanwhile, the risk of wasting scarce resources by ‘over designing’ is as real as the dangers of climate damage to under designed infrastructure.
 
To identify the optimal response of our client governments to this threat and to ensure that all transport infrastructure supported by the Bank is disaster and climate resilient, we have created a joint partnership between the Bank’s transport and disaster risk management (DRM) communities – a partnership of complementary expertise to identify practical cost-effective approaches to an evolving challenge. We have come together to better define where roads and other transport assets should be built, how they should be maintained, and how they can be repaired quickly after a disaster to enable swift recovery.

Three misconceptions in the way of better housing policies

Luis Triveno's picture
Also available in: 中文

Photo by Dominic Chavez / World Bank

​While the need for housing is widespread, individually people have different needs—depending on whether they are single, married, senior citizens, families with children, or members with disabilities. Despite the best of intentions of policymakers, "a roof overhead" remains an elusive goal for a large majority of the world’s people. Most households cannot afford even the cheapest house that fits their needs and qualifies as “decent,” and no government alone can close this gap with subsidies. Nor are we on track to build the 300 million new houses needed to close the housing gap by 2030.

What’s missing? At least three misconceptions stand in the way of better housing policies: 
 

Assessing disaster risk in Europe and Central Asia – what did we learn?

Alanna Simpson's picture
Heavy rains on June 13-14, 2015 caused a 1 million cubic-meter landslide to flow down the Vere River valley and damage the capital city of Tbilisi, Georgia. (Photo via Wikimedia Commons)
Across the Europe and Central Asia region today, policymakers are confronted daily with a wide range of development challenges and decisions, but the potential impacts of adverse natural events and climate change – such as earthquakes or flooding – may not always be first and foremost in their thoughts.

Admittedly, the region does not face the same daunting disaster risks as some other parts of the world – especially in South Asia, East Asia and Latin America – but nevertheless, it is far from immune to the effects of natural hazards – as the past clearly reminds us.

Inconvenient, apocalyptic, or somewhere in between? Why we shouldn’t be complacent about volcanic eruptions

Alanna Simpson's picture

A house destroyed by a volcanic eruption. Yogyakarta, Indonesia. Project: JRF. © Nugroho Nurdikiawan Sunjoyo/World Bank

Volcanic eruptions capture the imagination with their awe-inspiring power, but why don’t they capture the attention of decision makers and development professionals working to build resilient communities? People visit Pompeii in the shadow of Mt. Vesuvius, and see the once thriving community destroyed within minutes from a major past eruption, but it does not resonate with their day-to-day lives. We see spectacular footage of erupting volcanoes in the media, but we rarely think about what it means for communities who live within the reach of the multiple volcanic hazards that can occur during eruptions. 

This wasn’t always the case. For 11 years from 1980, volcanic eruptions were at the forefront of the minds of those working in disaster risk management. At the opening of the decade, Mt. St. Helens violently erupted, claiming the lives of 57 and causing over USD1 billion in damage in the USA. Two years later, El Chichon erupted in Mexico killing at least 2,000. In 1985, a very minor eruption of Nevada del Ruiz volcano triggered a massive deadly mudflow (lahar) that killed 23,000 people in the town of Armero, Colombia. A year later, 1,700 people were killed in their sleep by volcanic gases from Lake Nyos volcano in Cameroon.

Let’s build the infrastructure that no hurricane can erase

Luis Triveno's picture
Hati after Hurrican Matthew
Hurricane Matthew destroyed an estimated 90% of homes in Haiti's Grande Anse department. Stronger public knowledge infrastructure can help better facilitate post-disaster recovery.
(Photo: EU Delegation to the Republic of Haiti)
The news from Haiti about the aftermath of Hurricane Matthew is a familiar story: more chaos, rubble, and loss of life from another natural disaster. Though recent improvements to Haiti’s infrastructure at the local level kept the death toll at 534—3,000 died in the 2004 hurricane; more than 200,000 in the 2010 earthquake—the number is still way too high.
 
Worldwide, natural disasters claimed 1.3 million lives between 1992 and 2012, with earthquakes accounting for 60%of disaster deaths in low- and middle-income countries, where the preponderance of sub-standard housing increases the risks. Today, 1.2 billion people live in substandard housing. By 2030, this figure will almost triple.
 
The good news is that most of those deaths and property losses can be prevented. In 2003, for example, within three days of each other, earthquakes of similar magnitude struck Paso Robles, California and Bam, Iran. The death toll in Bam was 40,000—nearly half the city’s population. Two people died in Paso Robles.
 
Even when destruction does take place, proper planning and measures can ensure a speedy recovery.

Investing to make our cities more resilient to disasters and climate change

Joe Leitmann's picture

Urbanization comes at a price, especially in an era of climate change and increased risk of natural disasters.

Presently, the average annual loss from natural disasters in cities is estimated by the UN at over $250 billion. If cities fail to build their resilience to disasters, shocks, and ongoing stresses, this figure will rise to $314 billion by 2030, and 77 million more city dwellers will fall into poverty, according to a new World Bank/GFDRR report presented at COP22.

The good news is that we have a window of opportunity to make cities and the urban poor more resilient. Over 60% of the land projected to become urban by 2030 is yet to be developed. Additionally, cities will need to build nearly one billion new housing units by 2060 to house a growing urban population. Building climate-smart, disaster-resilient cities and housing is thus an immediate priority, especially in the developing world. 

To seize that opportunity, countries will need significant financing for infrastructure—over $4 trillion annually—and making this infrastructure low carbon and climate resilient will cost an additional $0.4 to $1.1 trillion, according to a CCFLA report.

Mobilizing private capital is the best bet for helping to close this financing gap.

On the road to resilience: Reducing disaster and climate risk in Africa

Ede Ijjasz-Vasquez's picture
As 60 million people in Africa await humanitarian assistance due to the worst El Nino in decades, the World Bank is actively engaged in 14 countries to plan recovery programs worth more than $500 million. (Photo: Flore de Preneuf / World Bank)


Natural disasters—such as droughts, floods, landslides, and storms—are a regular occurrence, but climate change is increasing the frequency and intensity of such weather-related hazards. Since 1970, Africa has experienced more than 2,000 natural disasters, with just under half taking place in the last decade. During this time, natural disasters have affected over 460 million people and resulted in more than 880,000 casualties. In addition, it is estimated that by 2030, up to 118 million extremely poor people (living below $1.25/day) will be exposed to drought, floods, and extreme heat in Africa. In areas of recurrent disasters, this hampers growth and makes it harder for the poor to escape poverty.

Watching Tanzania leapfrog the digital divide

Boutheina Guermazi's picture
 
Digital opportunities are the fuel of the new economy. They have significant impact on both the economy and society. They contribute to growth, create jobs, are a key enabler of increased productivity, and have significant impact on inclusion and poverty reduction. They also provide the ability to leapfrog and accelerate development in key sectors like health and education.
 
Why is this important?  It is important because “going digital” is not a temporary phenomenon. It is a revolution—what the World Economic Forum calls “the 4th industrial revolution”. It is happening before our eyes at a dizzying pace, disrupting every aspect of business, government and individuals’ lives. And it is happening in Tanzania.

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