Uncertainty is the new normal: the case for resilience in infrastructure

Members of the New York Urban Search and Rescue Task Force One help evacuate people from their homes in Fayetteville, North Carolina, in September 2018. Image: Getty.

The most recent international report on climate change paints a picture of disruption to society unless there are drastic and rapid cuts in greenhouse gas emissions. And although it’s early days, some cities and municipalities are starting to recognise that past conditions can no longer serve as reasonable proxies for the future.

This is particularly true for America’s infrastructure. Highways, water treatment facilities and the power grid are at increasing risk to extreme weather events and other effects of a changing climate.

The problem is that most infrastructure projects, including the Trump administration’s infrastructure revitalisation plan, typically ignore the risks of climate change.

In our work researching sustainability and infrastructure, we encourage and are starting to shift toward designing man-made infrastructure systems with adaptability in mind.

Designing for the past

Infrastructure systems are the front line of defense against flooding, heat, wildfires, hurricanes and other disasters. City planners and citizens often assume that what is built today will continue to function in the face of these hazards, allowing services to continue and to protect us as they have done so in the past. But these systems are designed based on histories of extreme events.

Pumps, for example, are sized based on historical precipitation events. Transmission lines are designed within limits of how much power they can move while maintaining safe operating conditions relative to air temperatures. Bridges are designed to be able to withstand certain flow rates in the rivers they cross. Infrastructure and the environment are intimately connected.

Now, however, the country is more frequently exceeding these historical conditions and is expected to see more frequent and intense extreme weather events. Said another way, because of climate change, natural systems are now changing faster than infrastructure.

How can infrastructure systems adapt? First let’s consider the reasons infrastructure systems fail at extremes:

  • The hazard exceeds design tolerances. This was the case of Interstate 10 flooding in Phoenix in fall 2014, where the intensity of the rainfall exceeded design conditions.

  • During these times there is less extra capacity across the system: When something goes wrong there are fewer options for managing the stressor, such as rerouting flows, whether it’s water, electricity or even traffic.

  • We often demand the most from our infrastructure during extreme events, pushing systems at a time when there is little extra capacity.

Gradual change also presents serious problems, partly because there is no distinguishing event that spurs a call to action. This type of situation can be especially troublesome in the context of maintenance backlogs and budget shortfalls which currently plague many infrastructure systems. Will cities and towns be lulled into complacency only to find that their long-lifetime infrastructure are no longer operating like they should?

Currently the default seems to be securing funding to build more of what we’ve had for the past century. But infrastructure managers should take a step back and ask what our infrastructure systems need to do for us into the future.


Agile and flexible by design

Fundamentally new approaches are needed to meet the challenges not only of a changing climate, but also of disruptive technologies.

These include increasing integration of information and communication technologies, which raises the risk of cyberattacks. Other emerging technologies include autonomous vehicles and drones as well as intermittent renewable energy and battery storage in the place of conventional power systems. Also, digitally connected technologies fundamentally alter individuals’ cognition of the world around us: consider how our mobile devices can now reroute us in ways that we don’t fully understand based on our own travel behavior and traffic across a region.

Yet our current infrastructure design paradigms emphasise large centralized systems intended to last for decades and that can withstand environmental hazards to a preselected level of risk. The problem is that the level of risk is now uncertain because the climate is changing, sometimes in ways that are not very well-understood. As such, extreme events forecasts may be a little or a lot worse.

Given this uncertainty, agility and flexibility should be central to our infrastructure design. In our research, we’ve seen how a number of cities have adopted principles to advance these goals already, and the benefits they provide.

A ‘smart’ tunnel in Kuala Lumpur is designed to supplement the city’s stormwater drainage system. Image: David Boey/creative commons.

In Kuala Lampur, traffic tunnels are able to transition to stormwater management during intense precipitation events, an example of multifunctionality.

Across the U.S., citizen-based smartphone technologies are beginning to provide real-time insights. For instance, the CrowdHydrology project uses flooding data submitted by citizens that the limited conventional sensors cannot collect.

Infrastructure designers and managers in a number of U.S. locations, including New York, Portland, Miami and Southeast Florida, and Chicago, are now required to plan for this uncertain future – a process called roadmapping. For example, Miami has developed a $500m plan to upgrade infrastructure, including installing new pumping capacity and raising roads to protect at-risk oceanfront property.

These competencies align with resilience-based thinking and move the country away from our default approaches of simply building bigger, stronger or more redundant.

Planning for uncertainty

Because there is now more uncertainty with regard to hazards, resilience instead of risk should be central to infrastructure design and operation in the future. Resilience means systems can withstand extreme weather events and come back into operation quickly.

Microgrid technology allows individual buildings to operate in the event of a broader power outage and is one way to make the electricity system more resilient. Image: Amy Vaughn/U.S. Department of Energy/creative commons.

This means infrastructure planners cannot simply change their design parameter – for example, building to withstand a 1,000-year event instead of a 100-year event. Even if we could accurately predict what these new risk levels should be for the coming century, is it technically, financially or politically feasible to build these more robust systems?

This is why resilience-based approaches are needed that emphasise the capacity to adapt. Conventional approaches emphasise robustness, such as building a levee that is able to withstand a certain amount of sea level rise. These approaches are necessary but given the uncertainty in risk we need other strategies in our arsenal.

For example, providing infrastructure services through alternative means when our primary infrastructure fail, such as deploying microgrids ahead of hurricanes. Or, planners can design infrastructure systems such that when they fail, the consequences to human life and the economy are minimised.

The Netherlands has changed its system of dykes and flood management in certain areas to better sustain flooding.

This is a practice recently implemented in the Netherlands, where the Rhine delta rivers are allowed to flood but people are not allowed to live in the flood plain and farmers are compensated when their crops are lost.

Uncertainty is the new normal, and reliability hinges on positioning infrastructure to operate in and adapt to this uncertainty. If the country continues to commit to building last century’s infrastructure, we can continue to expect failures of these critical systems, and the losses that come along with them.

The Conversation

Mikhail Chester, Associate Professor of Civil, Environmental, and Sustainable Engineering, Arizona State University; Braden Allenby, President's Professor and Lincoln Professor of Engineering and Ethics, School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University, and Samuel Markolf, Postdoctoral Research Associate, Urban Resilience to Extremes Sustainability Research Network, Arizona State University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 
 
 
 

What’s killing northerners?

The Angel of the North. Image: Getty.

There is a stark disparity in wealth and health between people in the north and south of England, commonly referred to as England’s “north-south divide”. The causes of this inequality are complex; it’s influenced by the environment, jobs, migration and lifestyle factors – as well as the long-term political power imbalances, which have concentrated resources and investment in the south, especially in and around London.

Life expectancy is also lower in the north, mainly because the region is more deprived. But new analysis of national mortality data highlights a shockingly large mortality gap between young adults, aged 25 to 44, living in the north and south of England. This gap first emerged in the late 1990s, and seems to have been growing ever since.

In 1995, there were 2% more deaths among northerners aged 25 to 34 than southerners (in other words, 2% “excess mortality”). But by 2015, northerners in this age group were 29% more likely to die than their southern counterparts. Likewise, in the 35 to 44 age group, there was 3% difference in mortality between northerners and southerners in 1995. But by 2015, there were 49% more deaths among northerners than southerners in this age group.

Excess mortality in the north compared with south of England by age groups, from 1965 to 2015. Follow the lines to see that people born around 1980 are the ones most affected around 2015.

While mortality increased among northerners aged 25 to 34, and plateaued among 35 to 44-year-olds, southern mortality mainly declined across both age groups. Overall, between 2014 and 2016, northerners aged 25 to 44 were 41% more likely to die than southerners in the same age group. In real terms, this means that between 2014 and 2016, 1,881 more women and 3,530 more men aged between 25 and 44 years died in the north, than in the south.

What’s killing northerners?

To understand what’s driving this mortality gap among young adults, our team of researchers looked at the causes of death from 2014 to 2016, and sorted them into eight groups: accidents, alcohol related, cardiovascular related (heart conditions, diabetes, obesity and so on), suicide, drug related, breast cancer, other cancers and other causes.

Controlling for the age and sex of the population in the north and the south, we found that it was mostly the deaths of northern men contributing to the difference in mortality – and these deaths were caused mainly by cardiovascular conditions, alcohol and drug misuse. Accidents (for men) and cancer (for women) also played important roles.

From 2014 to 2016, northerners were 47% more likely to die for cardiovascular reasons, 109% for alcohol misuse and 60% for drug misuse, across both men and women aged 25 to 44 years old. Although the national rate of death from cardiovascular reasons has dropped since 1981, the longstanding gap between north and south remains.

Death and deprivation

The gap in life expectancy between north and south is usually put down to socioeconomic deprivation. We considered further data for 2016, to find out if this held true for deaths among young people. We found that, while two thirds of the gap were explained by the fact that people lived in deprived areas, the remaining one third could be caused by some unmeasured form of deprivation, or by differences in culture, infrastructure, migration or extreme weather.

Mortality for people aged 25 to 44 years in 2016, at small area geographical level for the whole of England.

Northern men faced a higher risk of dying young than northern women – partly because overall mortality rates are higher for men than for women, pretty much at every age, but also because men tend to be more susceptible to socioeconomic pressures. Although anachronistic, the expectation to have a job and be able to sustain a family weighs more on men. Accidents, alcohol misuse, drug misuse and suicide are all strongly associated with low socioeconomic status.

Suicide risk is twice as high among the most deprived men, compared to the most affluent. Suicide risk has also been associated with unemployment, and substantial increases in suicide have been observed during periods of recession – especially among men. Further evidence tells us that unskilled men between ages 25 and 39 are between ten and 20 times more likely to die from alcohol-related causes, compared to professionals.

Alcohol underpins the steep increase in liver cirrhosis deaths in Britain from the 1990s – which is when the north-south divide in mortality between people aged 25 to 44 also started to emerge. Previous research has shown that men in this age group, who live in the most deprived areas, are five times more likely to die from alcohol-related diseases than those in the most affluent areas. For women in deprived areas, the risk is four times greater.


It’s also widely known that mortality rates for cancer are higher in more deprived areas, and people have worse survival rates in places where smoking and alcohol abuse is more prevalent. Heroin and crack cocaine addiction and deaths from drug overdoses are also strongly associated with deprivation.

The greater number of deaths from accidents in the north should be considered in the context of transport infrastructure investment, which is heavily skewed towards the south – especially London, which enjoys the lowest mortality in the country. What’s more, if reliable and affordable public transport is not available, people will drive more and expose themselves to higher risk of an accident.

Deaths for young adults in the north of England have been increasing compared to those in the south since the late 1990s, creating new health divides between England’s regions. It seems that persistent social, economic and health inequalities are responsible for a growing trend of psychological distress, despair and risk taking among young northerners. Without major changes, the extreme concentration of power, wealth and opportunity in the south will continue to damage people’s health, and worsen the north-south divide.

The Conversation

Evangelos Kontopantelis, Professor in Data Science and Health Services Research, University of Manchester

This article is republished from The Conversation under a Creative Commons license. Read the original article.