How Infrastucture Failures Affect Community’s Disaster Resilience

Natural hazards like floods and landslides often lead to road closures, limiting access and damaging vital infrastructure such as power and communication networks.

This can trigger a cascade of failures, where damage to one piece of infrastructure has a ripple effect on other essential services. Due to these disasters, access to critical facilities is denied directly or indirectly.

For instance, a school may be unable to operate without electricity, or a hospital or business might be crippled without water or sanitation services. When access to essential services is disrupted, it increases the strain on communities and weakens their resilience.

On the other hand, maintaining access to these services during and after disasters helps communities recover more quickly and strengthens their overall resilience. Access to these services also plays a crucial role in improving disaster preparedness.

The physical presence or proximity of essential services to communities doesn’t guarantee availability during or after disasters. Researchers from the University of Canterbury in Christchurch, New Zealand, studied how hazards impact communities, specifically focusing on whether essential services remain functional after an event.

Their paper, “Functional Isolation: The compounding burden on community capacity from cascading infrastructure failures and access disruption,” published in the International Journal of Disaster Risk Reduction in January 2025, introduces the concept of “functional isolation.” This occurs when communities are physically connected to what they need (e.g. healthcare, food, emergency services, etc) but gain no utility from these amenities due to failures in supporting infrastructure or supply chains required to operate them.

The authors use a new, detailed approach that combines previous research on access resilience with models showing how infrastructure failures can spread through transport, electricity, and water networks. They demonstrate that the direct effects of hazards on infrastructure and their indirect effects—such as infrastructure breakdowns, physical isolation, and loss of services—can significantly increase the burden on communities during and after disasters.

The interdependencies of infrastructure systems mean that the impact of a disaster on one system can have far-reaching effects on others and the communities they serve. For example, when a hazard damages the electrical grid and causes a power outage, it can also disrupt drinking water supplies and wastewater treatment plants that rely on electricity. This, in turn, can affect hospitals, supermarkets, schools, and other essential services. In this way, the damage to one piece of infrastructure can lead to widespread disruptions across multiple systems and communities.

In the same way, road damage can disrupt the delivery of essential supplies and equipment to critical services – like hospitals, supermarkets, and emergency systems- resulting in reduced service levels or even complete closures. When communities lose access to essential services or experience minimal access for days or even months after a disaster, it weakens their resilience and makes them more vulnerable.

Researchers, using coastal flooding events in Christchurch, New Zealand, as a case study, discovered that when functional isolation is included in their assessment, disaster impacts significantly increase as follows:

• When indirect effects were considered, non-functional amenities increased by 114% to 178%, and isolated residential buildings rose to 198%.
• When accounting for how different infrastructure systems are connected, the number of services that stopped working, like supermarkets, hospitals, and schools, increased by 114%, 178%, and 142%, respectively.
• For people who weren’t fully isolated, access to essential services was still heavily impacted, with travel distances to services increasing by 0.5 to 1 km and, in some cases, up to 27 km.

These findings show the importance of including functional isolation in disaster risk assessments, emergency planning, and strategies to improve community resilience. The method used in this study can be applied in many different situations, helping urban planners, policymakers, and emergency response management personnel better prepare for various types of hazards.

The rest of the paper is organised as follows: Section 2 explains how the study was done, including the data and methods used. Section 3 presents the case study results, and Section 4 discusses these results. Section 5 wraps up with recommendations for policy and ideas for future research.

Read the paper to learn more about how cascading infrastructure failures increase the pressure on communities. Visit the link below.