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Disaster resilience in the US

Atkins | 30 Jul 2015 | Comments

When it comes to disaster planning, it’s better to consider the worst rather than hope for the best.

Natural disasters are striking at rates higher than previously recorded. Impacts of climate change on weather volatility coupled with population growth and densification in urban areas mean that such catastrophes are not only occurring with more frequency than ever before, they are affecting more lives.

A report published last year by the World Meteorological Organization found that, between 2000 and 2009, there were 3,496 reported floods, storms, droughts and heat waves – nearly five times the 743 disasters reported during the 1970s. These destructive events have come to dominate headlines month in, month out, and this year is no exception.

On 24 May 2015, a storm system dumped record levels of rainfall on tracts of Texas and Oklahoma, putting a number of counties under a state of emergency as flood waters claimed at least 31 lives and caused millions of dollars’ worth of damage.

The Federal Emergency Management Agency (FEMA), the government body mandated to assess the damage caused by the flooding and award federal aid to those most in need, has tasked Atkins with carrying out 52,000 housing inspections in Texas and 5,000 in Oklahoma.

Cathy Clinch, vice president and senior division manager of Atkins’ federal business unit, says the housing inspections are expected to rise to as many as 100,000 assessments in Texas and 12,000 in Oklahoma.

“We’re at the front end of the spear,” she says. “We go out and support post-disaster with rapid perishable data collection to try and identify the floodline, the high water marks and extent of damage. We support post-disaster forensic analysis to determine how the infrastructure coped. We then look for any catastrophic failures to support further analysis to improve infrastructure and community planning to minimize the impact of future events”.

No two disasters are identical, although there are often similarities. For example, tornadoes inflict damage quickly and move on, whereas floods linger, inundating homes and giving rise to everything from mold risks, spoilt agriculture and a sense of community and government fatigue that makes the recovery process from large scale and catastrophic disasters all the more protracted.

Preparation, resilience

Providing a community that can withstand a natural hazard is only part of the story.

In 2003, The American Association of State Highway and Transportation Office (AASHTO) requested a report to address the unexpected challenges to provide physical security against terrorists’ attacks on their critical structures. The report concluded, “The actions of terrorists can impose critical damage to some bridges, and, with explosive forces, exert loads that exceed those for which components are currently being designed. Worse yet, in some cases, the loads can be in the opposite direction of the conventional design loads.”

True resilient communities can withstand a multitude of disasters including cyber threats, natural hazards, terrorism and pandemics. The United States Presidential Policy Directive 8: National Preparedness (PPD-8) (March 2011) is aimed at strengthening the “security and resilience” of the United States through “systematic preparation for the threats that pose the greatest risk to the security of the nation.”

The directive asks multiple federal agencies and the public and private sector to work together with communities to improve resilience. An integrated resilience approach means planning for one hazard in order to increase the resilience of the community in the wake of a other hazards. When this concept is applied to disaster events, being able to withstand and recover becomes a recognizable goal.

Much of the work in this field involves mitigation and planning for the future. When it comes to floods, this could mean anything from building floodways, levees, elevating structures to changing building codes/standards and local zoning. However, to be truly resilient, a community must recognize the interdependencies between infrastructure systems and understand how the threats will be impacted by all the proposed mitigation measures.

For example, a levee may impede flood water from entering a community but true community resilience looks at how the other threats, such as terrorism or a cyber-breach of the levee mechanisms, may impact the community.

“There is really no silver bullet. It takes a variety of disciplines coming together,” says Clinch. “We bring our engineering, cyber expertise, physical security consultants, coastal modeling, environmental, sociology and community planning experts together to assess how to build (or rebuild) a truly resilient community.”

Atkins’ tools

One of the most valuable tools for mapping out potential future natural disaster scenarios is HAZUS, a modeling program developed by Atkins and adopted by FEMA for risk awareness and disaster impact.

The software interprets fault lines and seismic activity, floodplains and storm activity and computes historical, hypothetical and predicted outcomes. Additionally, Atkins has developed StormCaster (AtkinsStormCaster.com), an integrated forecasting tool for projecting local impacts of climate change on size and frequency of major storms.

“This web based tool helps us focus on applying infrastructure improvements that will result in risk reduction associated with climate change and sea level rise. We take a proactive approach to resilience. We do not just mitigate based on the last storm, but also for future environmental conditions,” says Clinch.

“These tools are incredibly useful for conducting risk assessments and assessing potential consequences and enabling us to work with communities focusing on risk mitigation and reduction opportunities,” she adds.

“Depending on where you are in the country, hazards and consequences vary considerably – some regions are drought prone which are then more likely to experience wildfires and the cascading risks of flooding or mudslides. There are other regions that are more earthquake prone or regions which reside in hurricane prone areas. These varying regional hazards and risks are based on hydrologic/hydro geologic/ atmospheric and the consequence of that hazard is directly related to the resilience of the built environment.”

“Climate change doesn’t just mean higher temperatures, or more rain,” says Stephen Bourne, Atkins’ developer of StormCaster. “We’ve found that most often it means that the distribution of events is changing. Big storms are getting bigger. Big droughts are getting longer. In the future, towns may receive the same amount of annual rain they always did, but in much more dangerous events.”

In addition to PPD 8, governments have provided a legal basis for mitigation and recovery measures. In the US, the Disaster Mitigation Act of 2000 serves as a central document for FEMA. The Disaster Mitigation Act of 2000 provided the legal basis for FEMA mitigation planning requirements for State, local and Indian Tribal governments as a condition of mitigation grant assistance. This act amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act by repealing the previous mitigation planning provisions and replacing them with a new set of requirements that emphasize the need for State, local, and Indian Tribal entities to closely coordinate mitigation planning and implementation efforts.

Across the United States, resilience planning has become a top priority as water levels rise, storms grow more destructive, physical hazards and cyber-threats become more prevalent and populations compete for space. Integrated resilience, vigilance and preparation are now vital to avoid as much harm as possible.

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